# Power Sound Audio MTM-210 Speaker Review Discussion Thread



## AudiocRaver

[img]http://www.hometheatershack.com/gallery/file.php?n=38993&w=s[/img]
*Power Sound Audio MTM-210 Speaker Review Discussion Thread*




*PSA MTM-210: $799.50 each*


*by Wayne Myers*


*Introduction*

The Power Sound Audio MTM-210 is a recently introduced audiophile speaker from the Mineral Ridge, Ohio based speaker and subwoofer manufacturer. While the company's target market is primarily home theater enthusiasts, the MTM-210 caught my attention as an offering poised to cross into two-channel territory, and I was anxious to hear what co-founders Tom Vodhanel and Jim Farina had come up with. The two questions in my mind were:

Could the MTM-210 really be considered an audiophile speaker? and...
How well would it perform relative to other speakers in the under-$2000-per-pair price range?


*Go to the Power Sound Audio MTM-210 Speaker Reviewhttp://www.hometheatershack.com/for...audio-mtm-210-speaker-review.html#post1111641*​


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## AudiocRaver

This thread is now open for comments and discussion.


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## needspeed52

Wayne, thank you so much for all your hard work and time with evaluating the PSA MTM-210s. I have two questions if you don't mind? Which setup did you most prefer, the Front Wall Location or the Mid-Field Location?
Also I realize the importance of having the tweeters of a LCR trio of vertcally oriented 210s in the same plane, how detrimental would it be if the center's tweeter was 5" below the plane of the mains in a HT setting? Thanks again Wayne for all that you do, greatly appreciated. Looking forward to your reply.
Sincerely, Jeffrey


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## AudiocRaver

needspeed52 said:


> Wayne, thank you so much for all your hard work and time with evaluating the PSA MTM-210s. I have two questions if you don't mind? Which setup did you most prefer, the Front Wall Location or the Mid-Field Location?


My personal preference is the Mid-Field Location, it gets you closer to the sound field and is more immersive. Nothing wrong with the performance at the Front Wall Location, though. If the MTM-210s are to be used for both home theater and 2-channel listening, I would leave them by the wall, the setup requirements are too exacting to be moving them back and forth, IMO. Plus zero image shift with change of the LP left or right.

Elsewhere, I make recommendations for speaker setup where the mid-field location is recommended as the best way - the only way with some speakers - to get a big, well-defined soundstage. With a controlled-directivity horn-loaded tweeter like the MTM-210s, the rules change quite a bit. They give a good soundstage close to the front wall where most speakers do horribly, so there is much more flexibility with them. But the mid-field soundstage is a bit funner. Toe-in/listening angle make a big difference mid-field, the 15 degree off axis LA worked best for me.

I would not bother with REW to EQ extensively, certainly not with any auto-EQ products. The lift below 300 Hz with a single shelf filter helped a little, but was not really needed. If you can do that easily, fine, otherwise don't bother.



> Also I realize the importance of having the tweeters of a LCR trio of vertcally oriented 210s in the same plane, how detrimental would it be if the center's tweeter was 5" below the plane of the mains in a HT setting? Thanks again Wayne for all that you do, greatly appreciated. Looking forward to your reply.
> Sincerely, Jeffrey


While the soundstage is much more focused on the tweeter-to-tweeter line, it does have some vertical spread, and should be able to accommodate a 5" or 6" offset without being noticeable. At 8" to 12" I believe it would start be noticeable and a bit distracting.


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## bkeeler10

Thanks for another great review, Wayne. I have long had a sort of prejudice against horn-loaded tweeters, particularly those using compression drivers. Definitely great for lots of output, and great for sci-fi blockbusters in a home theater (one of the most impressive things I ever heard at a trade show was the shotgun scene at the beginning of Ratatouille as played by a system of horns, played VERY loud. Totally effortless like nothing else in my experience). However, it has always been my apparently uninformed opinion that they are shouty and potentially annoying and fatiguing over time, and not well-suited to two-channel music. Lately I've been reading a lot to the contrary though, so I guess I'm going to have to break down and try it some time.

Perhaps you could contrast the broad, overall character of this speaker with something totally on the opposite end of the spectrum, such as your EM ESL or the best of the cones'n'domes (or AMTs) that you've heard. You are obviously enthusiastic about this speaker, but it seems clear that it does distinguish itself from traditional consumer designs in some fundamental ways, which I'm curious about.


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## tesseract

I had a chance to hear the Power Sound Audio MTM-210 pair yesterday. I heartily recommend them for either music or movies, and the wave guided compression tweeter sounded natural, no hint of horn sound, no cupped hand qualities at all.

A consideration for those using directivity designs, try Wayne Parham's method. Get rid of any side wall first reflection absorption panels, set the speakers far apart and try a sharp 45 degree angle toe-in. Bouncing the sound off the side walls greatly increases the soundstage width, putting more listeners in the "sweet spot". I've talked to Wayne, experienced one of his systems in person and have tried it myself, it really does work. I'll venture a guess that the single 10" driver PSA MT-110 would provide even greater image focus, as that has been my experience with TM vs. MTM configurations.

There is also some interesting horn vs. wave guide info in the pdf.









As an aside, I have also adopted his "Flanking Subs" method. The MTM-210 pretty much requires sub augmentation, and flanking is a great way to minimize or eliminate floor bounce nulls.


Thank you for another thorough loudspeaker review, Mr. Myers!


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## needspeed52

As an aside, I have also adopted his "Flanking Subs" method. The MTM-210 pretty much requires sub augmentation, and flanking is a great way to minimize or eliminate floor bounce nulls.


Thanks Dennis for your input, when you say subs flanking the mains, could this mean that the subs could be inside or outside the mains. Right now I have my 210s LCR in a near front wall configuration with dual XS30SEs flanking on the inside of each main speaker. I'm thinking of moving the mains closer together and closer than the 36" from front wall which means I would have to move the subs (flanking) to the outside of the mains, would this be OK. In other words when you say flanking could this mean outside or inside the plane of the mains? 

Right now the mains are about 8' apart from each inside baffle of each other and from the mains plane the LP is about 10.5 ' away and the mains are toed in about 20 degrees. I don't think I can use the corner placement with 45 degree toe in method. Thanks for the time.
Cheers Jeff


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## tesseract

Jeffrey - I think going to the outside would be fine, that is how Mr. Parham does it. At the wavelengths we are talking about, you would have to separate your subs by quite some distance for it to matter. Of course, the higher the XO frequency, the greater the chance for sub localization.


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## AudiocRaver

Jeffrey, concerning your speaker location, I see no need to move them, they really allow a lot of flexibility. Are they pointed straight at the LP, with zero listening angle? Basically, the closer to the LP, the more off-axis listening angle they needed - 15 degrees was plenty, more might be OK. But farther from the LP, closer to the wall, a smaller LA is better, including zero LA (pointed straight at listener). There is some flexibility to all of this - these are the tendencies I noticed while working with the MTM-210s..

I like that you have them a few feet out from the wall but still close to it, better for home theater sound close to the wall and more spaciousness to the soundstage with that extra distance out from the wall, a good compromise.

Edit: Absolutely no harm in trying out Tesseract's suggestion if it works in your room, I can see its logic. My own room would not allow me to try it, either, no corners where a speaker can go.


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## needspeed52

AudiocRaver said:


> Jeffrey, concerning your speaker location, I see no need to move them, they really allow a lot of flexibility. Are they pointed straight at the LP, with zero listening angle? Basically, the closer to the LP, the more off-axis listening angle they needed - 15 degrees was plenty, more might be OK. But farther from the LP, closer to the wall, a smaller LA is better, including zero LA (pointed straight at listener). There is some flexibility to all of this - these are the tendencies I noticed while working with the MTM-210s..
> 
> I like that you have them a few feet out from the wall but still close to it, better for home theater sound close to the wall and more spaciousness to the soundstage with that extra distance out from the wall, a good compromise.
> 
> Edit: Absolutely no harm in trying out Tesseract's suggestion if it works in your room, I can see its logic. My own room would not allow me to try it, either, no corners where a speaker can go.


Thanks Wayne, yes the 210s are firing straight at the LP, considering I do most of my listening by my myself I want the money seat to be mine. I also have the advantage of no WAF as the misses doesn't care what I do in my space or how loud I do it.:T I remember reading some other reviews from you and you always liked bringing the speakers out into the room, so after your review I figured I would try to have it both ways, not way out into the room and not too far from front wall, like you said a good compromise. 

I like the fact that you say no EQ for the 210, I hear that so much with other speaker owners that say this is harsh or mid bass is missing but that's OK I can fix it with EQ. I don't have much room treatments at all and have to agree with you that these speakers do take a lot of the room out of the equation but still maintain that great imaging and sound stage. I'm also very happy to know you approve of the subs flanking the mains, I didn't know if this was the right way of doing this and let my ears by the judge. No localization at all crossed over at 80 Hz, the integration between mains and subs is seamless.

This is my first go at HE speakers with a CD horn loaded tweeter, I was really expecting that beaming effect and harshness but with proper placement I haven't experienced any of this, quite the opposite. I also added the MT-110s as sides and what a difference a 10" driver can make, I thought it would be overkill but I was wrong. Tom V said it all, "you don't what you're missing until you have it"

After thought: I could try the corner loaded mains with a 45 degree LA, my only concern is that I have all my gear on two DIY salamader racks which would place the speakers dispersion pattern in the way. The more I think about it, why change a good thing that you know works for me. So basically my LCR 210s are setup pretty much as your front wall location suggests just with a little different distances. The stands I built allow me to have each speaker the exact same height (mains) and I make sure they are perfectly level. I picked that up from your evaluation right away when you said one speaker was a 1/4" tilted.:T

Thanks again Wayne and Dennis, I know I made the right choice but I had to have it verified from someone who is familiar with the 210s, and the measurements confirm all that I'm hearing and what you heard. I'm still procrastinating with REW, so my speakers have no EQ at all, not even Audyssey and I'm liking what I hear. Take care and will talk soon.:clap:
Best Regards, Jeffrey


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## Tom V.

Hi Wayne,

First, thanks again for taking the time for such an in-depth review. As I have mentioned elsewhere you are on the way for being *the* benchmark for full range reviews. 

One question at a time (for me) for clarity.

First---the "narrow notch" at 200hz in this graph http://www.hometheatershack.com/gallery/file.php?n=39169&w=s

Could that be some type of "floor bounce" cancellation from the ground? I don't have all of our CLIO data-sets on this PC but I don't recall anything like this and it would seem unusual to see a notch like this from a 10" woof. 

Tom V.
Power Sound Audio


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## AudiocRaver

Tom V. said:


> Hi Wayne,
> 
> First, thanks again for taking the time for such an in-depth review. As I have mentioned elsewhere you are on the way for being *the* benchmark for full range reviews.
> 
> One question at a time (for me) for clarity.
> 
> First---the "narrow notch" at 200hz in this graph http://www.hometheatershack.com/gallery/file.php?n=39169&w=s
> 
> Could that be some type of "floor bounce" cancellation from the ground? I don't have all of our CLIO data-sets on this PC but I don't recall anything like this and it would seem unusual to see a notch like this from a 10" woof.
> 
> Tom V.
> Power Sound Audio


Great question, Tom. Obviously, I have real-world issues to deal with every time I take a measurement, not having access to an anechoic chamber or 100 ft high tower or the like. Reflections can make a mess of a frequency response plot, and I use the impulse response view to make sure all disruptive reflections are cleaned up in getting to a meaningful measurement plot.

Let me dig into my data and get back to you. I may take a few more measurements to see if there is a logical explanation.


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## AudiocRaver

AudiocRaver said:


> Great question, Tom. Obviously, I have real-world issues to deal with every time I take a measurement, not having access to an anechoic chamber or 100 ft high tower or the like. Reflections can make a mess of a frequency response graph, and I use the impulse response view to make sure all disruptive reflections are cleaned up in getting to a meaningful measurement graph.
> 
> Let me dig into my data and get back to you. I may take a few more measurements to see if there is a logical explanation.


Tom,

You are correct, that notch at 200 Hz is from floor bounce. Of course I am well aware of the phenomenon and the problems it can cause in taking measurements, and thought I had eliminated it from the measurements. I went through an interesting exercise figuring out how I missed it, and would like to share it with the community so we can all learn from the experience.

Impulse response graphs are fascinating and contain a wealth of information, and I find myself staring at them more and more these days. But they do not always give up their secrets easily, and sometimes the information we want the most is so subtle it is almost impossible to spot with the naked eye. In this case, the details we are talking about can easily be buried in noise.

I turned to modeling of the reflection phenomenon so we could see a clean and idealized version of what is going on. It is quite fascinating.

Several simulated measurements are shown, the ones we are discussing are numbered 2 through 6 in the legends of the graphs.

Frequency Response Simulations.
 

Impulse Response %FS, normal view and zoomed in.
  

Impulse Response DBFS - Simulation 3, damped reflection.
 

Impulse Response DBFS - Simulations 4 and 5, the reflection is covered by another anomaly.
  

Impulse Response DBFS - Simulation 6, simple minimum-phase filter at 200 Hz.


Simulation 2 is for a situation with a 1.7 mS delay for the reflected signal. That sounds shorter than we would look for with a 200 Hz dip in the frequency response, but there is a reason for using that number. The 1.7 millisecond delayed reflection causes of the first cancellation and dip at 300 Hertz (in the simulation, the reflected signal is attenuated by 10 dB, so cancellations are not complete, and the "rounded" comb filtering results). 

f1 = 1 / ( 2 x d )

f1 = 1 / ( 2 x 0.0017 ) = 300 Hz

The above formula gives the first attenuated frequency due to a reflection/cancellation. "Comb effect" filtering results, with additional cancellations at

f1 x 3
f1 x 5
f1 x 7
f1 x 9
etc

The %FS impulse response for Simulation 2 shows a clear, sharp spike at 1.7 milliseconds from that reflection, very much like I saw. 

Simulation 3 shows what happened when I damped out that reflection with blankets on the ground. The frequency of the dip appears to have moved from 300 Hz to 200 Hz. This is important to note, as it had me looking for indications of the delayed signal at the wrong time on the impulse response. The %FS impulse response graph shows that the spike is completely gone. The zoomed-in version of that graph shows us the result of filtering on that impulse, which is effectively what happened. The high frequency energy was absorbed and dissipated, but there was still quite a bit of lower frequency energy left, and it was spread out over time. The peak value of the resulting impulse is less than one percent of the original peak, so it is very difficult to see in that view. It showed up very clearly in the DBFS impulse response graph, why did I not see it there? Because it was buried in noise.

The explanation for this is shown over the next two simulations. Simulation 4 shows a small variation in frequency response, and the effect it has on the impulse response. It is invisible on the %FS graph, but shows up very well on the zoomed-in version of that graph and is loud and clear on the DBFS version of the impulse response graph.

Simulation 5 is the one that we learn the most from here. Its lesson is how easily the indication of one kind of frequency response disturbance can be buried by the indications of something else. The frequency response graph is very similar to what I measured for the MTM-210. The %FS impulse response is very clean until you zoom in. The truth is that very takes very little measurement noise for that kind of blip to be totally covered up and impossible to see with the naked eye. The DBFS impulse response also shows how easily one indicator can be mixed in with and hidden by another. A little bit of noise and the indications of the reflection we tried to damp out are obliterated and impossible to see. 

The final Simulation 6 shows the effect on the impulse response graphs of a simple minimum phase filter at 200 Hertz, just for the record, quite different from the delayed reflection's effect.

The big lesson here is that the indicators for sharp reflections are easy to see on the %FS graphs, but softened reflection are harder to spot and easily lost in the noise, yet can cause serious anomalies in the frequency response.

I have already changed the captions for the first two frequency response graphs in the MTM-210 Review indicating that the 200 Hz dips are from reflections. If I am able to get measurements retaken, I will change those also. The weather might not allow that at this time however.

Tom, thank you for your patience. If there is ever any part of a review that is not completely accurate, I will happily make corrections where needed. I am glad that you pushed back on this one. It actually ended up being a fascinating learning experience figuring out just what happened.

Let me know if you have more questions.


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## needspeed52

Wayne, you are a fascinating person, diligent,articulate and you take your work more seriously than anyone I have ever encountered. I just wanted to express my extreme gratitude for all that you do, thank you again my friend. I wish more people would get involved in this thread, with this wealth of information concerning the PSA speakers and the free shipping both ways the MTM 210s are a must audition especially after your painstaking review and concise graphs. :clap: Kudos to you Wayne and PSA for making affordable made in the USA audio products.
I'm a proud owner of both the speakers and subs and thanks to you I'm convinced I made the right choice.:T
Graciously yours, Jeffrey Nordi


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## AudiocRaver

Thanks, Jeffrey.


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## needspeed52

AudiocRaver said:


> Thanks, Jeffrey.


My pleasure and you're welcome.


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## Tom V.

Fantastic breakdown Wayne. Thank you very much for the easy to follow graphs. I've already linked this thread in multiple chat sessions!

Tom V.
Power Sound Audio


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## AudiocRaver

bkeeler10 said:


> Thanks for another great review, Wayne. I have long had a sort of prejudice against horn-loaded tweeters, particularly those using compression drivers. Definitely great for lots of output, and great for sci-fi blockbusters in a home theater (one of the most impressive things I ever heard at a trade show was the shotgun scene at the beginning of Ratatouille as played by a system of horns, played VERY loud. Totally effortless like nothing else in my experience). However, it has always been my apparently uninformed opinion that they are shouty and potentially annoying and fatiguing over time, and not well-suited to two-channel music. Lately I've been reading a lot to the contrary though, so I guess I'm going to have to break down and try it some time.
> 
> Perhaps you could contrast the broad, overall character of this speaker with something totally on the opposite end of the spectrum, such as your EM ESL or the best of the cones'n'domes (or AMTs) that you've heard. You are obviously enthusiastic about this speaker, but it seems clear that it does distinguish itself from traditional consumer designs in some fundamental ways, which I'm curious about.


Brian,

I understand your hesitation about horn-loaded tweeters. It seems to be hard to hide all signs of them being at work sonically.

My experience in doing direct a/b testing between Martin Logan electrostatics and the MTM-210 is that they sound surprisingly similar. The voicings are slightly different, the MTM-210 being flatter and more extended, while the ESL signature has a very slight rolloff partly due to my off-axis listening position, but other than that they're both very open and natural and completely at ease in their delivery. The sound stage for the MTM-210 is slightly dryer, due to the monopole controlled directivity. Dipole electrostatics get more going on in the room behind them, and the soundstage is a little more lively and spacious, but I would say neither is better or worse than the other, just slightly different. Again, the horn sound effect is completely absent with the MTM-210. I was glad to have Dennis, Tesseract, over recently to hear the MTM-210, and he agreed, as he has commented above, that they do not sound like horns at all.

Both MTM-210 and the ESL are exquisitely clean in their delivery. As I noted there were only a few occasions where the MTM-210 did not quite keep up with the cleanness level of the electrostatics, and that would never have even been noticed except with direct a-b testing where I was looking for that specifically in very dense tracks. Under normal circumstances there was never a time when I felt the MTM-210 were anything less than marvelously clean and that is a big factor in how much I liked them.


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## AudiocRaver

Tom V. said:


> Fantastic breakdown Wayne. Thank you very much for the easy to follow graphs. I've already linked this thread in multiple chat sessions!
> 
> Tom V.
> Power Sound Audio


Thank you, glad it was helpful.

You hinted that you might have more questions.:bigsmile:


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## bkeeler10

Hmm, well my audition list continues to grow. A year or two ago, I never thought I would consider electrostats or anything horn-loaded, and now I think I would be doing myself a disservice if I didn't give them both a good audition. I'll be blaming you, Wayne :hissyfit: :T


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## AudiocRaver

bkeeler10 said:


> Hmm, well my audition list continues to grow. A year or two ago, I never thought I would consider electrostats or anything horn-loaded, and now I think I would be doing myself a disservice if I didn't give them both a good audition. I'll be blaming you, Wayne :hissyfit: :T


The ESLs only ended up here because one of the pair we received for our Evaluation Event in Nov. of '13 was defective and I got a new pair at home to review. Once I realized what they were capable of, I could not let them go. I still have an "aaaaahhhhhh, that's what I was missing..." reaction when I return to them after working with most other speakers.

Except with the MTM-210s. It was purely a whim to contact PSA to review the MTM-210s, and I am surprised as you are that they stand up so well in comparison to the ESLs.

A word on "dynamics:" Horn-loaded speakers are said to be "more dynamic," something that I experienced, too, and I am trying to figure out just what that means. I think it must have something to do with the way the energy remains more focused by the horn than with a more dispersive cone type speaker or with a dipole set up as they normally are. HOWEVER......

When you get a dipole, like the ESLs for example, set up so the delayed arrivals of the rear reflections are synchronized - like down to 50 uS or so - then the "dynamics" of the electrostatics jump to a whole new level, one which rivals that of horns, IMO. It is a matter of energy focus, I am pretty sure.

I ramble... the point of it all being... AIN'T LIFE GRAND that it brings us surprises like these, and challenges like having to decide which fantastic speaker technology for the delightful immersion of our senses!


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## bkeeler10

Interesting stuff. You shouldn't have let slip your write-up about the electrostats -- I've got something to hound you about now :bigsmile:

It seems to me that most horn-loaded speakers have an emphasis on high efficiency of the system as a whole. When a speaker can chase you straight out of the room with only a couple watts of power, even on dynamic peaks they are literally idling by (and the amps driving them are idling too). I think that bodes well for "immediate" sounding dynamic capability and a sense of complete ease at even beyond sane listening levels. Of course, horn-loading and high efficiency go hand in hand since the energy created can be more "focused" if you will. But if your tweeter is horn-loaded, then you go looking for high efficiency woofers to match, I presume. The whole speakers/amp system is operating at very small percentages of its capacity, which is a good thing.

Now I'm rambling too. I'll be interested to read about your discoveries with the dipole reflections.


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## tesseract

needspeed52 said:


> Right now the mains are about 8' apart from each inside baffle of each other and from the mains plane the LP is about 10.5 ' away and the mains are toed in about 20 degrees. I don't think I can use the corner placement with 45 degree toe in method. Thanks for the time.
> Cheers Jeff


Jeff, 

No need to put the speakers in corners, the cross fire method works just as well when they are free standing. Glad to see you are enjoying the MTM 210's they are wonderful loudspeakers.


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## Tom V.

AudiocRaver said:


> A word on "dynamics:" Horn-loaded speakers are said to be "more dynamic," something that I experienced, too, and I am trying to figure out just what that means. I think it must have something to do with the way the energy remains more focused by the horn than with a more dispersive cone type speaker or with a dipole set up as they normally are.



Hi Wayne, I've been struggling with some of this too. I often have questions like this posed in emai/chat/phone. "I have xyz brand speakers(something with a 84-87dB sensitivity) what benefits would I notice if I try out your speakers". 

I always prefer being able to refer people to some sort of objective reference when asked questions like this. For example, I get the usual "I'm looking at sub XYZ and your sub, how do they compare. I just bring up a data-bass link and refer to that. But in this case, it isn't so easy to find quick, concise, and easy to understand references. 

I've been researching things like the dynamic range in music and the demands those peaks(up to 20-24dB) can put on a system. And then factor in the benefits of a speaker that is 10-12dB more sensitive...

Anyway, like you said...just thinking out loud..

Tom V.
Power Sound Audio


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## needspeed52

Thanks Dennis for that not needing to be in the corners, makes sense. Someone asked in another forum about the 1k dip in the FR graph, I know Tom V and Wayne addressed the 200 dip. I didn't even notice it till someone brought it up. Maybe you or Wayne can address it. It's not really a concern of mine just like the narrow dip at 200 wasn't. TIA
Cheers Jeff


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## AudiocRaver

Tom V. said:


> Hi Wayne, I've been struggling with some of this too. I often have questions like this posed in emai/chat/phone. "I have xyz brand speakers(something with a 84-87dB sensitivity) what benefits would I notice if I try out your speakers".
> 
> I always prefer being able to refer people to some sort of objective reference when asked questions like this. For example, I get the usual "I'm looking at sub XYZ and your sub, how do they compare. I just bring up a data-bass link and refer to that. But in this case, it isn't so easy to find quick, concise, and easy to understand references.
> 
> I've been researching things like the dynamic range in music and the demands those peaks(up to 20-24dB) can put on a system. And then factor in the benefits of a speaker that is 10-12dB more sensitive...
> 
> Anyway, like you said...just thinking out loud..
> 
> Tom V.
> Power Sound Audio


Tom,

There are numerous possible explanations for the more _dynamic sound_ of horn / high efficiency speakers, but no definitive explanations that I am aware of.

The possible explanations include things we discussed offline awhile back like the fact that power and heat dissipation in speaker components is lower and those components stay cooler and operate in their most linear modes. Then of course there is the fact that amplifiers can drive high efficiency speakers more easily and avoid clipping.

I see the logic in these explanations, but they do not seem to tell the whole story somehow. For one thing, there is no such thing as "occasional peaks" in most of the music that most of us listen to most of the time. Most music recorded in the last 20 years has peaks occurring at -1 dB to 0 dB on a constant basis. This is the norm, not the exception. Those who listen to classical, jazz, and unamplified instrumental music are exposed to a lot of dynamic range, but most other music has 10 or 12 dB of dynamic range if that. (Whether or not this is a good thing is another discussion - I am personally not too bothered by it but empathize with those who are.)

Taking a few measurements, it is easy to calculate the amount of power my AVR is putting out for different speakers I listen with. For an average 85 decibel listening level, which is about where I end up the majority of the time, the least efficient speaker I spend much time with is putting out under 4 W RMS average, under 40 W pk at 0 dB FS, and the signal simply can not go higher that that. This is taking into account very conservatively the possible impedance variations for the speakers in question. The amplifier can put out over 100 W continuous, and over 200 W dynamic. The MTM-210 demands only 3.5 W pk and 0.35 W RMS average for the same volume level. So while the MTM-210 is definitely demanding less power, I cannot find a way to argue that it is helping to avoid clipping in any way shape or form in this particular system. Solid-state linearities being what they are, distortion is a fast onset phenomenon, not one that creeps up slowly as with tubes or open-loop devices.

Yet there is definitely something more dynamic about the MTM-210 presentation. I am impressed by it almost every time I sit down and start to listen with them, and I hear similar comments by others who favor horns.

I know I am a broken record when it comes to the wonders of a great soundstage. But in them I see possible exclamations for mysteries that are otherwise unexplained. The high-directivity speaker design naturally helps one avoid uncoordinated early reflections which are disruptive to a clean sound stage. And an ultra clean sound stage has more open, empty space within it, allowing detail sounds to stand individually rather than be clumped together with other bigger sounds, and allowing all of the images in the sound field to have more impact in contrast to the deeper silence surrounding them. Achieving all of this is one of the talents of high directivity speakers. And Keeping the sonic energy more focused in the way it interacts with the listener seems a key factor in how it is achieved.

It is difficult to crunch all that down to a few words, but "more dynamic" works as well as any other term.


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## AudiocRaver

needspeed52 said:


> ...Someone asked in another forum about the 1k dip in the FR graph, I know Tom V and Wayne addressed the 200 dip. I didn't even notice it till someone brought it up. Maybe you or Wayne can address it. It's not really a concern of mine just like the narrow dip at 200 wasn't. TIA
> Cheers Jeff


Tom asked offline about the circumstances surrounding the distortion measurements, which are pretty smooth in the 200 Hz and 1 kHz regions. They were taken indoors with the speaker on the floor, tilted back, mic on the tweeter axis at 1 meter, and a lot of damping material on various surfaces to eliminate reflections visible on the impulse response plots. It came out quite clean, although there is still a "little something" going on at each of those frequencies. I am hoping to re-measure. Where is an anechoic chamber when you need one?


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## Tonto

Wayne wrote:



> The high-directivity speaker design naturally helps one avoid uncoordinated early reflections which are disruptive to a clean sound stage.


I think this pretty much sums it up. Horns do this so well when tuned correctly. If you think about it, we do this instinctively all the time ourselves. We cup our hands around our mouths when we need someone to hear us clearly. Focused directivity. 

You could probably demonstrate it by taking measurements with your hands cupped @ different angles in front of another speaker.


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## needspeed52

AudiocRaver said:


> Tom asked offline about the circumstances surrounding the distortion measurements, which are pretty smooth in the 200 Hz and 1 kHz regions. They were taken indoors with the speaker on the floor, tilted back, mic on the tweeter axis at 1 meter, and a lot of damping material on various surfaces to eliminate reflections visible on the impulse response plots. It came out quite clean, although there is still a "little something" going on at each of those frequencies. I am hoping to re-measure. Where is an anechoic chamber when you need one?


Thanks Wayne, your summation pretty much "sums" up the "little something" going on in each of those frequencies. I didn't realize those measurements were taken with the speaker on the floor, I'm very impressed with the rest of the frequency response and decided not to boost the 200 Hz dip. Thanks again Wayne for the relentless pursuit of perfection, you just won't stop until you're completely satisfied that you've done everything possible to address any anomalies. Kudos to you.:T
Cheers Jeff


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## AudiocRaver

Tom,

There I go getting totally lost in my little 2-channel world again. Obviously in my previous statement I was completely overlooking movies with their 20 dB dynamic range standard.

My previous statement stands true for the listening experience that I have had with the MTM-210. Given the same volume levels, listening to movie tracks, my amplification would have run into trouble for sure trying to handle another 10db of dynamic range with my less efficient speaker example. And with the MTM-210 would have had plenty of power to handle that dynamic range.

So this very example, with the projection of handling movie dynamics, supports your statement that a more efficient speaker will be better able to handle the kind of dynamic range many of your customers enjoy and be able to give excellent clarity and imaging and soundstage, all without amplification changes. There is no doubt that some movie enthusiasts would experience an immediate jump in available dynamics during louder passages in the movies they enjoy.

Please beg pardon in for my two-channel tunnel vision.


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## bkeeler10

Wayne, I just thought of another question I had. I have heard that some very high efficiency speakers are efficient enough to expose amplifier hiss audibly when connected but not playing anything. Did you find that to be the case here and have you ever encountered this before? Thanks.


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## needspeed52

bkeeler10 said:


> Wayne, I just thought of another question I had. I have heard that some very high efficiency speakers are efficient enough to expose amplifier hiss audibly when connected but not playing anything. Did you find that to be the case here and have you ever encountered this before? Thanks.


I have an all PSA 210s and 110s setup all driven with external amps (200 watts/channel) and they are whisper quiet. Hope that helps.
Cheers Jeff


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## bkeeler10

Good to know Jeff, thanks. What amp do you use with them?

Pretty sure you're the Jeff that owned a trio of Arx A5 a while ago and are a big fan of them. This is probably a ridiculous question but what do you see as the strengths and weaknesses of them and the MTM-210 compared to each other. Totally different speakers I know (at least in driver complement). Thanks


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## AudiocRaver

bkeeler10 said:


> Wayne, I just thought of another question I had. I have heard that some very high efficiency speakers are efficient enough to expose amplifier hiss audibly when connected but not playing anything. Did you find that to be the case here and have you ever encountered this before? Thanks.


At the LP (as opposed to with your ear up against the tweeter) only with a raised noise floor. Back when I was first discovering the soundstage capabilities of the ESLs, I had a wee bit of a raised noise floor in one particular system configuration due to some convoluted cabling and a ground loop. When the soundstage and imaging started to really sharpen and expose what should have been "dark" open spaces between images, I realized I could hear that noise in those spaces. For instance, a repeating echo on one B-52's song, at its own spot in the mix, got softer and softer, the 4th repetition was very soft and where there should have been a just audible 5th repetition, it was lost in that noise.

I changed a longer cable run to TOSLINK (optical), and the noise floor dropped by close to 20 dB (yeah, it was kinda bad before, for that particular configuration). Now those open spaces between images are completely dark. The 5th echo is audible in that darkness.

Switching to the more efficient MTM-210, that noise floor might be audible if it was elevated at all, but the dark areas remain completely dark and clear. A noise floor problem can happen with grounding/cabling noise, it can also happen with gain structure mismatches between pro and consumer gear (I think I had some of both going on). Nice thing about digital links is that they negate any gain structure mismatces while eliminating ground loops and associated noise.

Remember that monster amps tend to have more gain to be able to access the higher power levels. So a monster amp with no gain control, paired with a high efficiency speaker might be a combination that could end up with an audible noise floor.


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## Tom V.

AudiocRaver said:


> Tom,
> 
> There I go getting totally lost in my little 2-channel world again. Obviously in my previous statement I was completely overlooking movies with their 20 dB dynamic range standard.
> 
> My previous statement stands true for the listening experience that I have had with the MTM-210. Given the same volume levels, listening to movie tracks, my amplification would have run into trouble for sure trying to handle another 10db of dynamic range with my less efficient speaker example. And with the MTM-210 would have had plenty of power to handle that dynamic range.
> 
> So this very example, with the projection of handling movie dynamics, supports your statement that a more efficient speaker will be better able to handle the kind of dynamic range many of your customers enjoy and be able to give excellent clarity and imaging and soundstage, all without amplification changes. There is no doubt that some movie enthusiasts would experience an immediate jump in available dynamics during louder passages in the movies they enjoy.
> 
> Please beg pardon in for my two-channel tunnel vision.


 Hi Wayne, I haven't had time to really get into these measurements myself. People need to stop ordering our products so I can circle back to this. 

I'm assuming the dynamic range requirements have the potential to be as high as 20-24dB with anything recorded multi-channel. Movies and Concert discs for example. 

But even with 2 channel, I would think the potential is there for fairly big peak requirements from the system. Have you read this piece? 

http://www.soundonsound.com/sos/sep11/articles/loudness.htm

Thanks for sharing your thoughts too Wayne, this is something I've been struggling with for a while.

Tom V.
Power Sound Audio


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## needspeed52

bkeeler10 said:


> Good to know Jeff, thanks. What amp do you use with them?
> 
> Pretty sure you're the Jeff that owned a trio of Arx A5 a while ago and are a big fan of them. This is probably a ridiculous question but what do you see as the strengths and weaknesses of them and the MTM-210 compared to each other. Totally different speakers I know (at least in driver complement). Thanks


I use ATI and Emotiva amps, totally unnecessary but I like having them. All I can say is I really liked the A5s as most people knew, Wayne included, I spoke with him prior to the release of the PSA 210 review and asked him the same question. Well all I can say they are both very good speakers but the 210s are in one word "effortless" with what they do and they satisfy in both my two channel and HT listening habits. They can be subtle and then just so dynamic and the imaging and sound stage is so well defined with just the right blend of drawing you into the music and making you forget you're listening to wooden boxes. I hear things I haven't noticed before on tracks that I'm very familiar with, piano and the human voice are presented with uncanny character, I mentioned before while listening to a narrator on the Chesky Ultimate Test CD that I could almost tell what he looked like just from his voice in stereo mode, so many times I had to keep checking to see if I had the center channel on.

One thing I find myself doing on a regular basis is listening at levels that I would never have done in the past, these speakers like I said are so effortless and play without any ear fatigue or piercing sound at near or at reference levels. No strain and no noticeable distortion. I listened to the FOTP plane crash scene at reference with dual XS30SEs and my wife asked if I was insane or sick. Don't expect any forgiveness with these speakers as they are very revealing of source material, very true with what they are fed :T
EDIT: Free shipping both ways with 30 day audition and all made in the USA (except wave guide) and in house designed XO network. Don't wait for B-stocklddude:
Cheers Jeffrey


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## cez123

needspeed52 said:


> One thing I find myself doing on a regular basis is listening at levels that I would never have done in the past, these speakers like I said are so effortless and play without any ear fatigue or piercing sound at near or at reference levels. No strain and no noticeable distortion. I listened to the FOTP plane crash scene at reference with dual XS30SEs and my wife asked if I was insane or sick. Don't expect any forgiveness with these speakers as they are very revealing of source material, very true with what they are fed :T
> EDIT: Free shipping both ways with 30 day audition and all made in the USA (except wave guide) and in house designed XO network. Don't wait for B-stocklddude:
> Cheers Jeffrey


I'm not sure how some people listen to movies at reference levels... 

But! My Yamaha receiver is blocked, by me, at -10 MV. I have watched scenes at that volume, but I usually watched movie at around -20 or so (Polk Monitors).

I got the MTM-210s on last Thursday. Friday evening my wife had to work, so I had the chance to properly calibrate the system and test a few scenes. After watching the intro of Star Trek (2009), I decided to watch the whole movie... at -10! Holy moley, it was incredible. The effortless presentation and sound stage of the 210 is truly remarkable. 
I also watched The Royal Tenenbaums with my wife yesterday (-15 MV), and was very pleased with the subtle sounds coming from the speakers... I am really digging these bad boys.

I am, however, struggling with its dimensions. Very deep at 16". The Sanus stand that I have are way too flimsy for them, so I ended up going with concrete blocks - surprisingly, my wife isn't bothered by them, "as long as the speakers sound good"... am I lucky or what?! 
I might get a second XS30se and use them as the stands themselves, but that will have to wait a bit.

The one thing that I have not had a chance to play with is placement. As of now, they are in the corners, shooting at the MLP at a 45 degree angle. Music sounds incredible, and I have not missed a center channel - for the majority of time.

I'll try to bring them in and see how they sound... but I doubt very much that I'll be returning the MTM-210s.

Tom and Jim did a fantastic job on these speakers. I am one happy camper!


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## AudiocRaver

cez123 said:


> I'm not sure how some people listen to movies at reference levels...


No kidding. A fairly dead room makes it easier to listen at those levels, but I'll bet most people listen at 5 to 10 dB below that.


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## AudiocRaver

cez123 said:


> I am, however, struggling with its dimensions. Very deep at 16". The Sanus stand that I have are way too flimsy for them, so I ended up going with concrete blocks - surprisingly, my wife isn't bothered by them, "as long as the speakers sound good"... am I lucky or what?!


Wow, you are having a good week. Time for an extra hug, maybe flowers.


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## Tom V.

Hi Wayne,

Here is a recently published paper you might find interesting. Some interesting thoughts on topic.

http://www.audiomatica.com/wp/wp-co...Loudspeakers-at-low-Frequencies-with-CLIO.pdf

Tom V.
Power Sound Audio


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## cez123

AudiocRaver said:


> Wow, you are having a good week. Time for an extra hug, maybe flowers.


I _am_ very luck. Flowers and chocolate is a fair price to pay for all the gear in the living room. WAF has never been a problem for me.

She told me she's happy to keep getting upgrades for "free" anyway... I pay, she enjoys a bit too. I guess it's a advantageous trade-off for the both.


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## needspeed52

cez123 said:


> I _am_ very luck. Flowers and chocolate is a fair price to pay for all the gear in the living room. WAF has never been a problem for me.
> 
> She told me she's happy to keep getting upgrades for "free" anyway... I pay, she enjoys a bit too. I guess it's a advantageous trade-off for the both.


Congrats on your wonderful partner and your new 210s, I had a sneaking feeling you'd like them:T I had them on my dual XS30SEs for a while until I could build stands to support them and they sounded and looked good that way. I'm going to try that corner loading and 45 degree toe in and see what happens. Mine are out into the room about 3-4' and about 8.5' apart and 10.5 to LP with them toed in about shoulder width, you could start there and slowly move them out (toe in) and see how the stage opens up or gets narrower, the off axis listening is great, that center image is always spot on. Welcome to the PSA Family. Misses smiles you smile.:sn:
Cheers Jeff


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## AudiocRaver

Tom V. said:


> Hi Wayne,
> 
> Here is a recently published paper you might find interesting. Some interesting thoughts on topic.
> 
> http://www.audiomatica.com/wp/wp-co...Loudspeakers-at-low-Frequencies-with-CLIO.pdf
> 
> Tom V.
> Power Sound Audio


Tom,

Thank you for the article. I have played with the technique a little, sounds like a good time to delve into it more deeply. The article answers some questions for me. I am always looking for ways to refine the accuracy of my test methods.


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## needspeed52

AudiocRaver said:


> Tom,
> 
> Thank you for the article. I have played with the technique a little, sounds like a good time to delve into it more deeply. The article answers some questions for me. I am always looking for ways to refine the accuracy of my test methods.


I see very little room for refining the accuracy of your measurements Wayne, if there is any at all. Thank you for a job well done. I'd like to see some other owners impressions of their PSA speakers.

Here's a couple of pics of my front stage and what's inside a PSA speaker, I know I need a projector......coming and some panels:T


Cheers Jeffrey


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## Peter Loeser

Great looking setup! It sounds fantastic no doubt. 

Man, the Three Stooges marathon brings back memories of watching those as a kid with my dad on New Year's Eve every year.


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## needspeed52

Peter Loeser said:


> Great looking setup! It sounds fantastic no doubt.
> 
> Man, the Three Stooges marathon brings back memories of watching those as a kid with my dad on New Year's Eve every year.


Thanks my friend, yeah the Stooges were guys I watched as a kid with my brothers, back in the fifties.lddude:
It was amazing how the sound effects always matched the action and fanatic actions of the stooges.


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## Peter Loeser

Yes! The sound effects were one of the best parts!


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## AudiocRaver

Nice pics. You really dug into yours. I opted not to dissemble the tweeter like you did. You almost need 5 hands to do all that and get it all back together again!


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## needspeed52

AudiocRaver said:


> Nice pics. You really dug into yours. I opted not to dissemble the tweeter like you did. You almost need 5 hands to do all that and get it all back together again!


Tell me about it Wayne, the wrench would get stuck to the very strong magnet and trying to hold both the CD and horn and unbolt it at the same time was one crazy task, but I wanted people to see what detail goes into the production of these speakers, all done in house and the aluminum wave guide is the only foreign component on the entire speaker, all made in the USA.:T
Cheers Jeff


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## needspeed52

This was asked of me about the PSA 210s and I presented it to Jim Farina who kindly answered the questions.

1) what's the crossover point for the speakers? 1.7kHz 
2) what's the crossover order? The acoustical crossover order is 4th order.
3) the FR measurements at HTS found a dip at just over 1000 Hz similar in magnitude to the one at around 200Hz which as Tom pointed out was a floor bounce issue. When I mentioned this at AVS, I had hoped Tom would comment. As near as I can make out from the individual driver measurements at HTS, this seems to possibly be because there's not enough extension for the individual drivers such that when they sum, it leaves a hole. Now if this happens in the region of the crossover point, I'm wondering why weren't additional efforts made to eliminate it? In and around 1-5 kHz is where our hearing is most sensitive. If they're using a 4th order LR, maybe it needed to be a bit more complex. Sometimes they wire the tweeter and woofer out of phase to get rid of the notch. We experimented with removing the notch, but decided it wasn't worth it. All of our solutions would either cause other issues, or they weren't noticeable in our listening sessions. We felt the final solution was the best option. 
4) the reviewer comments that from the step response measurements you can tell the bass is tight. Really? I challenge you to fin in any of the Stereophile speaker measurements where they've made such conclusions. So, some elaboration and justification seems warranted. Examples of speakers with not tight bass. Maybe even a discussion of the speaker alignment such as whether the design was for maximally flat, minimum settling time, etc. Tight, fast, quick, are all terms relating to the frequency response of the subwoofer. If you can measure the frequency response you can calculate the impulse response and the step response. You will see how long it takes for the subwoofer to go from the initial impulse to rest . The shorter the time, the "tighter" the bass. I'll see if I can find any articles relating to the topic. 

Cheers Jeffrey


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## AudiocRaver

It is way after the fact, but I am cleaning up some old items on my todo list and had promised Tom an updated main frequency response plot in the review. I had taken more in-room measurements just before sending the MTM-210 pair back to him, and the following composite plot was very representative of what I had seen at different distances on the tweeter and mid-bass driver axes. New smoothing options are being tested in a beta of REW. Psychoacoustical smoothing follows FR peaks quite closely but is less sensitive to notches, depending on width and depth. Equivalent Rectangular Bandwidth (ERB) then applies frequency-dependent windowing, as the ear is less sensitive to reflected information at higher frequencies. ERB also smooths more at LF and less at HF, just as our hearing reacts with musical sources (vs. sine waves).




I just re-read the following and have a little commentary to add.



needspeed52 said:


> 3) the FR measurements at HTS found a dip at just over 1000 Hz similar in magnitude to the one at around 200Hz which as Tom pointed out was a floor bounce issue. When I mentioned this at AVS, I had hoped Tom would comment. As near as I can make out from the individual driver measurements at HTS, this seems to possibly be because there's not enough extension for the individual drivers such that when they sum, it leaves a hole. Now if this happens in the region of the crossover point, I'm wondering why weren't additional efforts made to eliminate it? In and around 1-5 kHz is where our hearing is most sensitive. If they're using a 4th order LR, maybe it needed to be a bit more complex. Sometimes they wire the tweeter and woofer out of phase to get rid of the notch. We experimented with removing the notch, but decided it wasn't worth it. All of our solutions would either cause other issues, or they weren't noticeable in our listening sessions. We felt the final solution was the best option.


The above (new) frequency response plot has no LF cancellation issues from reflections.

Concerning the Relative Driver Contributions plot in the review: In these reviews, I try to make information available that will be of value to potential buyers and users of the equipment, and put that information in a context that makes it meaningful. Sometimes I do not do that as well as at others. I now see that the plot could imply there is a huge hole between the response curves of the two drivers, which is not the case at all. Depending on how close the measurement is taken to the tweeter, and just how well centered it is, there can be some narrow notches in the frequency response just above 1 kHz where those drivers are overlapping. Of course, the closer you measure to the tweeter, the more they will stand out.

I have one set of measurements which were taken at 1 foot increments out to 5 feet, with a reduced IR window used to cut out reflection disturbances, and at three and even four feet some of those narrow notches at around 1.1 kHz to 1.4 kHz were still there. But at 5 feet it really cleaned up nicely and there was no evidence of those notches and good driver integration was indicated. Okay, so maybe *that* plot should have been in the review, right? _Hindsight, where are thou when I need thee?_

The fine people who make products like these, like Tom and Jim and the PSA team, might shudder a little when they see a review full of measurements ripe to be picked and misinterpreted or misused in some way. I appreciate their patience and understanding that our intention is not to make life difficult for them at all but to facilitate communications between them and potential buyers that can be as clear and open as possible. But once in awhile Tom and Jim end up jumping through hoops answering questions that they wish they didn't have to address because from their perspective they do not exist except for the silly measures some reviewer posted on a web page.

I do not apologize for communicating information in my reviews as clearly and accurately as I can, hopefully for the benefit of manufacturers and potential buyers and users. I do apologize for any shortsightedness or oversights that lead to trouble for anyone on either side or any misunderstandings. But I ain't perfect - - - If I mess up, let me know and I will do what I can to make it right. I am always looking for ways to do my job better.

That diagram seemed useful at the time, in hindsight it was probably not the best perspective of what I was trying to accomplish. I will probably remove it from the review. The speakers are gone, so I have no way of providing a better one, and it would not be a major loss to the review anyway. Apparently it sent you (Jeffrey) chasing a non-problem, which I kinda apologize for, but at the same time I’m chuckling a little thinking _Really?_ Sorry, with all the fine qualities of those speakers, it would not have occurred to me to try to fix that without actually hearing a problem there, which I never did.



> 4) the reviewer comments that from the step response measurements you can tell the bass is tight. Really? I challenge you to fin in any of the Stereophile speaker measurements where they've made such conclusions. So, some elaboration and justification seems warranted. Examples of speakers with not tight bass. Maybe even a discussion of the speaker alignment such as whether the design was for maximally flat, minimum settling time, etc. Tight, fast, quick, are all terms relating to the frequency response of the subwoofer. If you can measure the frequency response you can calculate the impulse response and the step response. You will see how long it takes for the subwoofer to go from the initial impulse to rest . The shorter the time, the "tighter" the bass. I'll see if I can find any articles relating to the topic.
> 
> Cheers Jeffrey


Any speaker that contributes to the bass range in a system can contribute to or detract from the perception of tightness or quickness of that bass. Plus, most of my listening to the MTM-210 was done without subwoofer. I assure you, the MTM-210 do put out bass frequencies (below 125 hZ), and they sounded and felt tight and quick to me, in the very way you described above, just not _deep,_ which is understandable.

Information that pertains to bass performance, including quickness, exists in the frequency response plot _combined with phase response,_ in the step response, and in the impulse response. As you say, they are all related. However, some things are easier to see in one view than in another. Some low frequency information is not easy to glean from an impulse response or step response.

The step response is the integral of the impulse response, and the impulse is the derivative of the step response. Neither one represents a situation or signal that the speaker will ever be subjected to in reality, although there are signals that come close. A gunshot can be close to an impulse, and a synthesizer square wave at a low frequency is close to a step response at each edge of the wave. Tight bass response can be seen in a frequency response that rolls off cleanly without any large low frequency peaks - indicating resonances - at or near that roll off. One nice thing about a step function is that it contains all frequencies and will excite resonances. Those resonances will be seen as ringing that follows the step. Since that ringing is sinusoidal, it will show up equally in both the step response and the impulse response, The integral and derivative functions of a sine wave give another sine wave of the same magnitude but different phase, and magnitude is what we're looking for in the impulse or step response and how fast it dies out. Most loudspeaker step and impulse responses show some resonances. They may indicate problems and they may not, they are more pointers of what directions to look in and see if there is a problem.

With headphones, I have seen that ringing and then set up tests to see if I could hear it. Knowing exactly what frequency to listen for helps a lot. Sometimes I have been able to hear it with the right music, other times even knowing it was there, I could never hear it. So seeing ringing in an impulse or step response does not mean trouble necessarily, it just means here is something to be aware of see if it shows up in the listening experience.

The MTM 210 tweeter exhibited some ringing in the 15 kilohertz range. I was not so much concerned about hearing the ringing as I was that that extra motion of the tweeter might cause distortion during physical passages with a lot of upper mid and high frequency content where the tweeter was being kept very busy. I have heard things like that in other tweeters where there was ringing or unusual extra motion seen in the impulse response. I went looking for it with the MTM-210 and was not able to find any example where there was any hash or audible messiness that resulted from what I thought was the ringing in the tweeter, and I tried to make that very clear in the review.

Quick bass will be indicated by absence of that ringing or ringing which dies down very quickly at the frequencies involving the cut-off point of the woofer or slightly above it where there are resonant peaks. Ringing that dies down in a few cycles, a few milliseconds basically, is associated with very tight, quick bass. No resonance at all means the bass is overdamped and that it could sound a little deeper and a little quicker with a little carefully controlled resonance.

And all due respect to the many other fine reviewers and resources out there, I do not feel beholden to use their same methods. I feel no compunction to justify my methods by saying _so and so does it, too._ I love science, science in the service of art is a great thing. What frustrates me a little is when people drop some big name in the industry and expect everyone to just stop thinking for themselves and bow down without argument. I would rather hear you speak your mind about how something should work or how you understand it to work or how you have experienced it, with reference to the theory and studies when it serves the discussion, then we can communicate and learn from each other.

So, no, I can quote no authority who says this is the right way to do it, but I am more than happy to discuss the principles, the science, the math involved and show how it makes sense to me. if you can show me that it does not, I will gladly find another way to do it.

Jeffrey, we have exchanged numerous fun and friendly posts in the past, I hope you do not feel like this is an attack or disrespectful or negative in any way, you simply - shall we say - put out a little friendly step function in of a couple questions, and it excited a couple of resonances in me that I happened to feel like blabbing about so, there you go.

Hope your MTM-210 setup is treating you well. Your friend,

Wayne


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## needspeed52

Wayne, those are not my comments, those are comments from someone else trying to find fault with the 210s, I have them as LCRs and 110s as surrounds and have no fault with them at all. I really like these speakers and speak nothing but praise about them and you for taking the time and effort to do what you do my friend.

Wayne those paragraphs are from someone else that I was quoting as he could not ask these questions for himself, so please you and everyone else reading this, THOSE ARE NOT ME SAYING THAT. I was being used as the scapegoat and didn't even realize it. I don't even know what those statements mean let alone be able to ask those questions in that terminology, seriously. Wayne I wish you would have talked to me about this as I'm totally unaware of these statements and believe me totally incapable of asking them and putting the words to paper.
Thank you Wayne again, you just reinforced my feelings for these speakers that play way beyond their asking price. I am not chasing anything, I found it my friend with PSA.

Wayne your friendship is priority one with me,, I really mean that, I don't know how this got so misconstrued, please know those are not my words at all. Your review of the 210s prior to this post was in my opinion as precise and informative as one could ask for and reinforced my feelings for these speakers. Thank you Wayne for reading this and I hope all is well between us, I recommend PSA products to everyone who will listen, and once they do it's quite evident why I advocate the brand the way I do. I have no affiliation with PSA except to be a proud and satisfied customer.

Best Regards, Your Friend Jeffrey


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## needspeed52

Wayne I found where those statements came from, they are on this thread early in the discussion, here is the exact quote from that page. That's how this got started. I hope it's all OK now my friend and we will continue to be so.

Jeffrey




This was asked of me about the PSA 210s and I presented it to Jim Farina who kindly answered the questions.

1) what's the crossover point for the speakers? 1.7kHz 
2) what's the crossover order? The acoustical crossover order is 4th order.
3) the FR measurements at HTS found a dip at just over 1000 Hz similar in magnitude to the one at around 200Hz which as Tom pointed out was a floor bounce issue. When I mentioned this at AVS, I had hoped Tom would comment. As near as I can make out from the individual driver measurements at HTS, this seems to possibly be because there's not enough extension for the individual drivers such that when they sum, it leaves a hole. Now if this happens in the region of the crossover point, I'm wondering why weren't additional efforts made to eliminate it? In and around 1-5 kHz is where our hearing is most sensitive. If they're using a 4th order LR, maybe it needed to be a bit more complex. Sometimes they wire the tweeter and woofer out of phase to get rid of the notch. We experimented with removing the notch, but decided it wasn't worth it. All of our solutions would either cause other issues, or they weren't noticeable in our listening sessions. We felt the final solution was the best option. 
4) the reviewer comments that from the step response measurements you can tell the bass is tight. Really? I challenge you to fin in any of the Stereophile speaker measurements where they've made such conclusions. So, some elaboration and justification seems warranted. Examples of speakers with not tight bass. Maybe even a discussion of the speaker alignment such as whether the design was for maximally flat, minimum settling time, etc. Tight, fast, quick, are all terms relating to the frequency response of the subwoofer. If you can measure the frequency response you can calculate the impulse response and the step response. You will see how long it takes for the subwoofer to go from the initial impulse to rest . The shorter the time, the "tighter" the bass. I'll see if I can find any articles relating to the topic. 


I pray Wayne this quote puts this travesty to rest once and for all and we can continue to be friends. That is my hope............

Cheers Jeffrey


Read more: http://www.hometheatershack.com/for...review-discussion-thread-5.html#ixzz3cicemruU


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## AudiocRaver

Jeffrey,

Thank you for the kind and patient response and for clearing that up. They did not sound like your own words, and I see now that you were quoting someone else with the questions. Absolutely no problem at all, of course, and although I may have overreacted a little bit with my comments, they were things that were on my mind and I was probably going to end up saying most of it somewhere anyway, although they should not have been directed at you. Plus they were questions I had missed previously and needed to be addressed so that is done as well.

All is well, and I am tickled that you are still tickled with your MTM-210 trio. I kind of miss them once in awhile myself.

Take care,

Wayne


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## needspeed52

Wayne, to further clarify:

OP's question:3) 
the FR measurements at HTS found a dip at just over 1000 Hz similar in magnitude to the one at around 200Hz which as Tom pointed out was a floor bounce issue. When I mentioned this at AVS, I had hoped Tom would comment. As near as I can make out from the individual driver measurements at HTS, this seems to possibly be because there's not enough extension for the individual drivers such that when they sum, it leaves a hole. Now if this happens in the region of the crossover point, I'm wondering why weren't additional efforts made to eliminate it? In and around 1-5 kHz is where our hearing is most sensitive. If they're using a 4th order LR, maybe it needed to be a bit more complex. Sometimes they wire the tweeter and woofer out of phase to get rid of the notch.

Jim's response:
We experimented with removing the notch, but decided it wasn't worth it. All of our solutions would either cause other issues, or they weren't noticeable in our listening sessions. We felt the final solution was the best option. 

OP Again:
4) the reviewer comments that from the step response measurements you can tell the bass is tight. Really? I challenge you to fin in any of the Stereophile speaker measurements where they've made such conclusions. So, some elaboration and justification seems warranted. Examples of speakers with not tight bass. Maybe even a discussion of the speaker alignment such as whether the design was for maximally flat, minimum settling time, etc. 

Jim's response: Tight, fast, quick, are all terms relating to the frequency response of the subwoofer. If you can measure the frequency response you can calculate the impulse response and the step response. You will see how long it takes for the subwoofer to go from the initial impulse to rest . The shorter the time, the "tighter" the bass. I'll see if I can find any articles relating to the topic. 

Wayne, sorry to keep elaborating on this matter but it's important to me that the truth be told. The OP used me to ask these questions as he is banned from this site and can not post, he did post over at AVS. Jim was kind enough to answer these blatant attacks on Power Sound Audio. Graphs and measurements do not tell the whole story, all this over a small dip in FR, I could only imagine if there were more of these dips what would happen........PSA has nothing to hide and your review certainly shows that with the time and effort you put into this evaluation, Kudos to PSA and you Wayne for the excellent work.

Thank you Wayne also for the kind words in the previous post, I'm so happy this was resolved and that our friendship is intact. :T
Best Regards, Jeffrey Nordi


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## AudiocRaver

Jeffrey,

Thank you for bringing clarity on the matter. I see now there were several voices mixed together in those remarks.

No worries on my part. PSA always answered any questions satisfactorily and with patience and class. My only reason for even posting at all was to try to be as accurate as possible about a fine product, not to stir a bee's nest, which appears to have been the bigger outcome. My apologies to all for that.

Thanks again, Jeffrey, all is well, so let's both move on to more important matters.

Have a great day,

Wayne


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## needspeed52

AudiocRaver said:


> Jeffrey,
> 
> Thank you for bringing clarity on the matter. I see now there were several voices mixed together in those remarks.
> 
> No worries on my part. PSA always answered any questions satisfactorily and with patience and class. My only reason for even posting at all was to try to be as accurate as possible about a fine product, not to stir a bee's nest, which appears to have been the bigger outcome. My apologies to all for that.
> 
> Thanks again, Jeffrey, all is well, so let's both move on to more important matters.
> 
> Have a great day,
> 
> Wayne


Yes Wayne let's do that my friend. Keep up the excellent job of educating the uninformed such as myself.
Likewise, have a wonderful day.
Jeffrey


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