# Purchased Three Tweeters!!! Opinions on mids and lows?



## hoovie87 (Aug 7, 2010)

Guys,

I just pulled the trigger on three new Klipsch THX Ultra 2 tractrix titanium 1" horns I found. I have always liked the sound of a Tractrix horn design, so I went ahead and bought three for L C R. I am so excited to hear these.

I am considering using the following drivers:

1. Dayton Audio RS270-8 10" Reference Woofer

2. Tang Band W4-1337SD 4" Titanium Driver (mid)

3. Along with the THX Ultra2 7" x 10" Horn Tweeter with 1" Titanium Compression Driver

I haven't purchased any mids or lows yet and was curious of opinions on these. I haven't decided on a cabinet size for each driver yet since I haven't yet used the software to test them. But, most likely in my head I am thinking larger ported box for the woofer with a small sealed box inside that for the mid within the woofer box. I would cross over the speakers at 300Hz ish and 4,000Hz ish with an L-Pad on the tweeter to keep it consistent with the mid.

So any opinions on the mids and lows? 

They seem like a great match of price to features. The titanium also on the mid to pair up with the tweeters. My goal is good 40Hz or lower response on these cabs and as natural as possible as they will be for home cinema mostly. I hope they provide the good dynamics and detail. I have 120W RMS per channel available for them from my Elite VX-42. I plan to replace the Klipsch F-10 towers I have.




Regards, 
David

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## NBPk402 (Feb 21, 2012)

What are you going to do for crossovers? I was going to suggest the MiniDSPs, but you would have to run a Tri-amp setup I believe. Sounds like it will be a nice project. :T


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## hoovie87 (Aug 7, 2010)

ellisr63 said:


> What are you going to do for crossovers? I was going to suggest the MiniDSPs, but you would have to run a Tri-amp setup I believe. Sounds like it will be a nice project. :T


I considered that, but cost of a new receiver and amps I can't afford. I don't have preamp outputs on this receiver except LFE. True though that would be so nice and easy.

Passive crossovers. Not sure on slopes yet.

Regards, 
David

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## NBPk402 (Feb 21, 2012)

I fully understand... My setup was budget too. I had to go with the miniDSPs as the Denon kept setting my crossover from the horns to the bass bins at the wrong frequency. The only way to correct it was to lower the gain on the horns, and raise the gain on the bass bins. I am using T chip amps for my horns. They were only $60 for a 25wpch stereo amp.


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## fusseli (May 1, 2007)

If you are doing passive crossovers take your time and go slow. It will majorly pay off to get the design right and avoid having to go back and fix things. Please ask for help and/or PM me directly and I will be glad to help as my time allows. In general active xovers are desirable for their ease of tweaking and simplicity, at the penalty of the hardware/DSP and extra amp channels. You don't lose anything by going passive, it's just more work up front.

With the 10" RS woofer you should do well in a large vented cab and get to 40 Hz easily, so good approach there. A true ~100W RMS amp will be great for this application in a three-way.

For the crossover slopes, you will want to exactly target an even number of octaves. This has to do with the phase response of the drivers. Three is a good number to shoot for, i.e. 300/2400 Hz.

The mid and the woofer you have chosen have nicely flat responses and should be "easy" to work with :T The woofer will be the weak point of the system in terms of sensitivity, so you may need considerable tweeter padding to get it down to the same level as the woofer and mid (horns having inherently high sensitivity).


-Have you done any speaker builds before?
-Do you have a speaker tester like for measuring drivers with REW, or a Dayton DATS?
-Do you have a calibrated mic to take driver measurements with? This will be especially needed if you can't find frequency response data for the Klipsch horns.
-Have you used any crossover design software before?


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## hoovie87 (Aug 7, 2010)

fusseli said:


> For the crossover slopes, you will want to exactly target an even number of octaves. This has to do with the phase response of the drivers. Three is a good number to shoot for, i.e. 300/2400
> 
> 
> -Have you done any speaker builds before?
> ...


-I have done many speaker builds before
-I will be needing guidance on software and test mic good for the money, but accurate.
-I didn't know there was crossover design software. Which one is good? I normally look at charts and whatnot for the components or buy pre-made/designed.

Can that tweeter go down to 2,400Hz? Is 600Hz and 4,800 maybe better or to much on the mid? Should I consider using two woofers per cabinet? It doesn't seem necessary to keep up with the mid.

It looks like the cabinet will be flat to around 23Hz. However, the high group delay will make it kind of weird under about 35Hz from what I am seeing. Tuning it really low seems to keep the group delay down over 40Hz. I love some tight low end. That is a must.


Regards, 
David

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## fusseli (May 1, 2007)

hoovie87 said:


> -I have done many speaker builds before
> -I will be needing guidance on software and test mic good for the money, but accurate.
> -I didn't know there was crossover design software. Which one is good? I normally look at charts and whatnot for the components or buy pre-made/designed.
> 
> ...


No idea on your tweeters man, you'll need to lookup some data for those Tractrix horns. You could measure them to find the Fs or go by the crossover point in some speakers they are used in.

Your midrange looks good up to 4800 Hz based on the specsheet! The only consideration is that woofers don't have as good of dispersion as tweeters for high frequency so it would be better to stay towards the lower kHz if possible. 

I would recommend a calibrated mic like one from Cross Spectrum Labs. You can get a UMM6 for cheaper elsewhere but then you have to trust the manufacturer's cal file.

For crossover design I am familiar with PCD7 that runs in Excel, which has since been converted into a windows app http://www.speakerdesign.net/WinPCD/


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## dgmartin (Oct 29, 2011)

Nice project. Are you going to use subs with these? The reason I'm asking is you could consider more sensitive drivers (to match the horn) for the same cabinet size if the last octave of extension is not required.


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## hoovie87 (Aug 7, 2010)

fusseli said:


> No idea on your tweeters man, you'll need to lookup some data for those Tractrix horns. You could measure them to find the Fs or go by the crossover point in some speakers they are used in.
> 
> Your midrange looks good up to 4800 Hz based on the specsheet! The only consideration is that woofers don't have as good of dispersion as tweeters for high frequency so it would be better to stay towards the lower kHz if possible.
> 
> ...


Awesome thanks! And true. I forgot about the beaming on higher frequencies.

Regards, 
David

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## hoovie87 (Aug 7, 2010)

dgmartin said:


> Nice project. Are you going to use subs with these? The reason I'm asking is you could consider more sensitive drivers (to match the horn) for the same cabinet size if the last octave of extension is not required.


I would like these to extend all the way down since they will be used for cinema. I think movies sound better with full ranges all the way around and a good LFE; especially in my room where it low end is spotty. It separates the sounds more and has greater dynamics from what I can hear. It's possible that I just don't like hearing that crossover point on my speakers I have now.

Regards, 
David

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## hoovie87 (Aug 7, 2010)

Actually, thinking twice, is there a better more efficient option for me on the mids and lows? Sound quality is most important though. If there are decently prices drivers you would suggest that are more efficient with flat frequency responses definitely let me know. I am continuing to look at all options.

I would like the speakers to reach to an f3 under 40Hz though.

I have considered two woofers since they will couple, but I need to find an efficient mid then with good dispersion.

Regards, 
David

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## fusseli (May 1, 2007)

Two woofers would help sensitivity of the low end, if you did that and a different midrange you could probably get a big boost in sensitivity. For the woofers you could do two RS180-8 and do a 3.5-way speaker design. This would get you +3dB gain in efficiency and be the same cost as one RS270. For the midrange there is the dome RS52AN-8 which would match the materials of the RS woofers. Depending on what you find out about your horns lower limit, you might even be able to ditch the midrange and do a 2.5-way with two woofers and the horn.


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## hoovie87 (Aug 7, 2010)

fusseli said:


> Two woofers would help sensitivity of the low end, if you did that and a different midrange you could probably get a big boost in sensitivity. For the woofers you could do two RS180-8 and do a 3.5-way speaker design. This would get you +3dB gain in efficiency and be the same cost as one RS270. For the midrange there is the dome RS52AN-8 which would match the materials of the RS woofers. Depending on what you find out about your horns lower limit, you might even be able to ditch the midrange and do a 2.5-way with two woofers and the horn.


For a .5-way design would the easiest thing be to just use a 24dB/oct so they are in phase? It seems like they would interfere at the crossover frequency a little. I haven't ever done that, but have used speakers that have that design.

Regards, 
David

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## hoovie87 (Aug 7, 2010)

The RS225-8 would be a better fit for the size of cabinet I need and low feq. extension it looks like.

Regards, 
David

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## hoovie87 (Aug 7, 2010)

Anyone have a suggestion on port location for it to have the best relationship with the woofers? Anyone know the trade off of having them up high, near the floor, in the back, or etc.? They will be placed right in front of a wall.

Regards, 
David

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## fusseli (May 1, 2007)

For a .5-way both woofers are below the same LPF but one, the .5, has an extra series inductor as to contribute little to HF and only support LF. Simple as that and no interference.

Bass where a port contributes is far into the omni-directional range, and where wavelengths are quite large so distance from the woofers isn't so important, so port placement matters little. Go for what's aesthetic to you.


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## dgmartin (Oct 29, 2011)

hoovie87 said:


> Actually, thinking twice, is there a better more efficient option for me on the mids and lows? Sound quality is most important though. If there are decently prices drivers you would suggest that are more efficient with flat frequency responses definitely let me know. I am continuing to look at all options.
> 
> I would like the speakers to reach to an f3 under 40Hz though.
> 
> I have considered two woofers since they will couple, but I need to find an efficient mid then with good dispersion.


I understand you want 40Hz F3 to have multiple sources of LF rather than a single sub. Have you thought about multiple subs?

Sorry I did forget to ask about acceptable cabinet size to fully define your constraints... As far as bass response is concerned efficiency is roughly proportional to the cube of F3 times the box volume. Thus the box volume and F3 will pretty much fix the woofer sensitivity (which will limit the system sensitivity). You will then have a better idea of the target midrange sensitivity if this is something you want to optimize. Do not forget the system sensitivity need to be a couple dB less than the woofer's due to BSC (4pi to 2pi space). Probably your initial driver suggestions already reflects that.

About the dispersion, I'm really not sure about he horn's directivity but maybe a 6-7in driver's narrower directivity (compared to the 4-incher) will be better matched to the horn at the crossover point (for what it's worth, this is the woofer size the original speaker uses). On the other hand, I don't recall any drivers of this size without breakups below, say, 5-6kHz. The breakup can be dealt with in the XO. 

It must have been posted hundred times, but this link could help target some good value drivers of different efficiencies. http://zaphaudio.com/6.5test/. I think high-efficiency pro midranges are out of scope but maybe 89-90db/W/m could be attainable. I'm not sure if it's there but the seas prestige line (CA**RN*) have decent sensitivity. The Dayton woofers are not bad choices either although they traded efficiency for extension/box size.


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## hoovie87 (Aug 7, 2010)

I was able to start testing out the tweeters. I found that with a 6.5kHz 12dB/Oct butterworth XO, these tweeter are flat from about 3kHz on up. They have a smooth tapering off under that which would be a really good spot at 2kHz to 2.5kHz to cross over the mid. The tweeter actually have great response down to 1kHz, but it sounds better crossed over high.

Regards, 
David

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## hoovie87 (Aug 7, 2010)

dgmartin said:


> I understand you want 40Hz F3 to have multiple sources of LF rather than a single sub. Have you thought about multiple subs?
> 
> Sorry I did forget to ask about acceptable cabinet size to fully define your constraints... As far as bass response is concerned efficiency is roughly proportional to the cube of F3 times the box volume. Thus the box volume and F3 will pretty much fix the woofer sensitivity (which will limit the system sensitivity). You will then have a better idea of the target midrange sensitivity if this is something you want to optimize. Do not forget the system sensitivity need to be a couple dB less than the woofer's due to BSC (4pi to 2pi space). Probably your initial driver suggestions already reflects that.
> 
> ...


What do you mean by multiple subs? Like using a 10" and 18" and crossing them over, or using two or three in different parts of the room? And why sound wise did you mention it. I am just curious.

Regards, 
David

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## hoovie87 (Aug 7, 2010)

fusseli said:


> For a .5-way both woofers are below the same LPF but one, the .5, has an extra series inductor as to contribute little to HF and only support LF. Simple as that and no interference.
> 
> Bass where a port contributes is far into the omni-directional range, and where wavelengths are quite large so distance from the woofers isn't so important, so port placement matters little. Go for what's aesthetic to you.


Just getting back I have been so busy. I tested what you are talking about as best I could. I used the new tweeters I have and found crossed at 6.5k and 12dB/Oct butterworth they are pretty flat to 3kHz and then roll off. I then used the woofer from my current synergy F-10 speaker to test and see what configuration sounds best to me. The extra woofer configurations was another F-10 next to the other. I used two XTI 1002 amplifiers for the testing. I time aligned the tweeter, used a small amount of EQ to flatten the woofer, then tested the following:

1. Three way with a 300Hz X-over on one woofer 24dB/oct, 300Hz to 2.5kHz, on second woofer, and the tweeter on up.

2. 2.5-way with the extra woofer crossed over at 250Hz 12dB/oct, 2.5kHz x-over

3. 2-way with a 2.5kHz x over

4. Dual woofers 2-way 2.5kHz

Now I had never tested what a .5 sounds like. It was a difficult toss up between 2.5-way and 3-way for me sound quality-wise. At low volumes, the 2.5-way design sounds very nice with tighter lows and low mids. However, as the volume rises and one gets off-axis, the midrange clarity went away. The three way setup did not have as impressive lows, but the mids were much clearer at high volumes and off axis. So either one has a slight trade off in my tests. What I am thinking is using two woofers in a straight-up three way configuration would be pretty sweet. I enjoy 24dB/oct crossovers more after switching back and forth as well. Except, the only way to achieve a flat tweeter response was the 12dB butterworth at 6.5kHz. It would need a ton of EQ if crossed over with a greater slope.

Is it a pain to build 48dB/oct XO filters and what do you think of them? I just assumed I don't want to use that many components.

Regards, 
David

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## hoovie87 (Aug 7, 2010)

I have really been thinking about efficiency mentioned above. What are your thoughts or experience on one of these in a two-way design along with the horn tweeter:

http://www.parts-express.com/tang-band-w8-1772-8-neodymium-full-range-driver--264-893

Or

http://www.parts-express.com/tang-band-w8-1808-8-neodymium-full-range-driver--264-894

Regards, 
David

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## dgmartin (Oct 29, 2011)

hoovie87 said:


> What do you mean by multiple subs? Like using a 10" and 18" and crossing them over, or using two or three in different parts of the room? And why sound wise did you mention it. I am just curious.


First I was trying to understand why you were aiming for that kind of LF extension on your mains while using a sub and your explanation led me to hypothesize that you were getting better integration of you sub when your mains were also contributing as low frequency sources (something I also experienced). In some way, this gives you the equivalent of having multiple subs in different parts of the room. I was thinking that ultimately by adding more subs you could achieve the same effect and relieve you mains' spec from an octave of LF and get more efficient/dynamic mains that take some advantage from the horn efficiency.


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## dgmartin (Oct 29, 2011)

hoovie87 said:


> I have really been thinking about efficiency mentioned above. What are your thoughts or experience on one of these in a two-way design along with the horn tweeter:


Never heard them or seen their response measured. Only experience I have with "full range" is with a 6.5in Fostex. You might have better luck on diyaudio or SET amp forums. 

General considerations:
Like any 8in paper cone, they will have resonances in their operating range. They also have rising response so real-world efficiency is not that high once tamed down. Vas is >3cu.ft. Would still use them in a 3-way. A dedicated pro midrange might do a better job for less. 

It is again a question of woofer efficiency, required F3 and box volume...


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## fusseli (May 1, 2007)

hoovie87 said:


> Just getting back I have been so busy. I tested what you are talking about as best I could. I used the new tweeters I have and found crossed at 6.5k and 12dB/Oct butterworth they are pretty flat to 3kHz and then roll off. I then used the woofer from my current synergy F-10 speaker to test and see what configuration sounds best to me. The extra woofer configurations was another F-10 next to the other. I used two XTI 1002 amplifiers for the testing. I time aligned the tweeter, used a small amount of EQ to flatten the woofer, then tested the following:
> 
> 1. Three way with a 300Hz X-over on one woofer 24dB/oct, 300Hz to 2.5kHz, on second woofer, and the tweeter on up.
> 
> ...


Interesting subjectivity on the results. If it were me I would do the 2.5-way. A 3-way with matching drivers for the mid and low would be a little odd not to mention inefficient in the bass region.

Stick with the same slopes if you can, to integrate the drivers the electrical crossover will give the drivers the same acoustic slopes. You might not need a 4th order electrical to get a 4th order acoustic roll off. Depends on the driver. For example, a 1st order electrical can be enough to give a woofer an effective 12dB/oct LPF due to its inherent drop off at HF. That being said there are great benefits for 12 and 24dB/oct Linkwitz Riley slopes for the "sweet spot" listening environment, I would say do that over odd-order slopes (6 and 18 dB/oct).


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## hoovie87 (Aug 7, 2010)

dgmartin said:


> First I was trying to understand why you were aiming for that kind of LF extension on your mains while using a sub and your explanation led me to hypothesize that you were getting better integration of you sub when your mains were also contributing as low frequency sources (something I also experienced). In some way, this gives you the equivalent of having multiple subs in different parts of the room. I was thinking that ultimately by adding more subs you could achieve the same effect and relieve you mains' spec from an octave of LF and get more efficient/dynamic mains that take some advantage from the horn efficiency.


When I get to it, it would probably be just as good if I build a sub for each side and I'll have the same effect. I understand...good idea

Regards, 
David

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## hoovie87 (Aug 7, 2010)

dgmartin said:


> Never heard them or seen their response measured. Only experience I have with "full range" is with a 6.5in Fostex. You might have better luck on diyaudio or SET amp forums.
> 
> General considerations:
> Like any 8in paper cone, they will have resonances in their operating range. They also have rising response so real-world efficiency is not that high once tamed down. Vas is >3cu.ft. Would still use them in a 3-way. A dedicated pro midrange might do a better job for less.
> ...


I have been thinking about efficiency, but I can't find woofers and mids except professional ones that are efficient. I am not experienced enough to know if an 87dB at 1w/m and 80W to it will have enough headroom. Looking for a comfortable 85dB from the speakers at 12ft away.

The paper cone was a concern of mine for sure.

Regards, 
David

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## hoovie87 (Aug 7, 2010)

By the way, are the Klipsch THX Ultra2 speakers 2.5 way or two way? I see lots of speakers two way with two woofers. I don't know how that would sound up at the higher frequencies...

Regards, 
David

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## hoovie87 (Aug 7, 2010)

Question - would it be worth my time to build a midrange tractrix horn?

Regards, 
David

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## dgmartin (Oct 29, 2011)

hoovie87 said:


> I have been thinking about efficiency, but I can't find woofers and mids except professional ones that are efficient. I am not experienced enough to know if an 87dB at 1w/m and 80W to it will have enough headroom. Looking for a comfortable 85dB from the speakers at 12ft away.
> 
> The paper cone was a concern of mine for sure.


Professional drivers are efficient and handle more power in general than "high-end" drivers. I guess it all starts from the bottom line that today's high-end woofers are designed for extension in small boxes, hence are not efficient. Then there is no point making their matching midrange efficient. More efficiency is obtained with multiple drivers. The pro drivers are not as pretty, are not made of unobtainium, but in my mind there is no doubt some sound as good as their "high end" counterparts. 

As for the headroom it is tough to describe the subjective effect although the math is pretty simple to _estimate _ SPL at LP from speaker sensitivity and distance (+3db per 2x power, -6db per 2x distance, +6dB per 2x speaker). So 87db/1w/1m corresponds to ~93dB at 4m and 64W but this is peak (considering one speaker). From that you need to remove the dynamic range/crest factor of the recorded material. I think the calculations are meaningful in a relative way, i.e. compared to a reference.



hoovie87 said:


> Question - would it be worth my time to build a midrange tractrix horn?


Probably not. At this point this is another topic than the OP but, there are Oblate spheroidal waveguides available which are optimized for SQ/directivity rather than efficiency (still in the pro-driver efficiency territory).


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## hoovie87 (Aug 7, 2010)

Based on the feedback I have been receiving, I am going to build along with the tractrix tweeter, dual 8" 4 ohm reference woofers series to 8 ohm, and the Tang Band W4-1337SDF 4" titanium full range for mids. That driver is slightly more efficient than the neo titanium driver.

I am hoping that the extra 3dB in efficiency will compensate enough for baffle step under 350Hz with the two woofs. It should be okay since one of the speakers will be in half space and one in quarter space.

The only two question is in your opinion, it it worth it to build in a physical delay for the tweeter? I tested it and can for sure hear a difference, but nobody ever seems to compensate. I just don't know how I'd build the cabinet with the tweeter sticking out. 

The last question is - would the dayton reference paper woofer or aluminum woofer be more accurate? I noticed the paper woofer is more efficient down low.

Thanks for the help everyone.

Regards, 
David

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## dgmartin (Oct 29, 2011)

hoovie87 said:


> The only two question is in your opinion, it it worth it to build in a physical delay for the tweeter? I tested it and can for sure hear a difference, but nobody ever seems to compensate. I just don't know how I'd build the cabinet with the tweeter sticking out.


Troels Gravesen does it on all its recent speakers (in this case it is the tweeter recessed wrt the woofers). Check it's Jensen line for instance. If the woofer flange is flat on the front, it is also possible to mount it from behind the baffle (which is recessed inside) and round over the baffle cutout (see recent Gedlee Abbeys for example). Both techniques lend themselves better to a painted baffle than a veneered one.


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## hoovie87 (Aug 7, 2010)

dgmartin said:


> Troels Gravesen does it on all its recent speakers (in this case it is the tweeter recessed wrt the woofers). Check it's Jensen line for instance. If the woofer flange is flat on the front, it is also possible to mount it from behind the baffle (which is recessed inside) and round over the baffle cutout (see recent Gedlee Abbeys for example). Both techniques lend themselves better to a painted baffle than a veneered one.


This is a great idea. Would recessing the midrange affect the frequency response much after rounding over the cutout? This is a great idea to at least get some delay without having the horn sticking out so much. Thanks for the idea.

Regards, 
David

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## hoovie87 (Aug 7, 2010)

Anyone know about whether the Dayton Reference aluminum or paper woofer would sound more accurate? One has more sensitivity down low. Any suggestions there?

Regards, 
David

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## dgmartin (Oct 29, 2011)

hoovie87 said:


> This is a great idea. Would recessing the midrange affect the frequency response much after rounding over the cutout? This is a great idea to at least get some delay without having the horn sticking out so much. Thanks for the idea.


The question about the midrange is good one for which I don't have quantitative answers, only a few (food for) thoughts. My only experience with mounting from the back involves a 10in driver and the concern is irrelevant.

The additional mass due to the air load is 3 order of magnitude less than Mms so LF performance should not be affected.

The book from Martin Colloms mentions a possible cavity resonance in the range of 2000Hz for a 25mm dome (this caused a ±1.5dB ripple). Based on very rough calculation this frequency seems to be possible. For a 4in midrange the axial resonance should also exist. Rounding over the edge (R = thk) on a 4 in driver will increase the Area/Volume of the cavity and push that resonance up, likely in the 3000ish. There should be an increase in directivity. The best would be to have a 1in radius (tangent to the baffle) on a ¾ baffle so that it forms a shallow horn (and push the resonance further up).

For what it’s worth, respected manufacturers such as Spendor and Harbeth have done that, without the roundover… Many pro midranges have their gaskets on the front.

The same book mentions that the diffraction from using stepped baffle impair the performance far more than the benefits of time delay. The author does not show data to support his statement. I’m sure other designers have different views...


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## hoovie87 (Aug 7, 2010)

dgmartin said:


> The question about the midrange is good one for which I don't have quantitative answers, only a few (food for) thoughts. My only experience with mounting from the back involves a 10in driver and the concern is irrelevant.
> 
> The additional mass due to the air load is 3 order of magnitude less than Mms so LF performance should not be affected.
> 
> ...


Good info. It helped in my searching of rear mounting!

Regards, 
David

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## hoovie87 (Aug 7, 2010)

After placing my options into Win ISD, I am going to choose dual 8" 4 ohm paper woofers. They have substantially more output down under my XO than the aluminum ones at the slight sacrifice of an f3 at 45Hz. No big deal for 4dB more efficiency. I probably won't have to bother with baffle step since they are more efficient than the mid. They will also handle 180W before over excurting instead of 80W like the aluminum ones as well according to Win ISD.

I want to try my hand at rear mounting with roundover to get a little better time delay with the tweeter because that sound like it will help and look cool!

Now, would Win ISD be giving me an accurate group delay at 300Hz? It is showing almost .8ms difference between the mid and the woofer. That can't be right, can it?

Regards, 
David

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## dgmartin (Oct 29, 2011)

hoovie87 said:


> Good info. It helped in my searching of rear mounting!


Great! Please post any findings about quantitative effects if you found something.

Besides, I was wondering if you considered using a separate cabinet for the woofers (i.e. a bass module). That would allow you to experiment with other tweeter/midrange combinations, even a conventional bookshelf actively crossed-over etc... 

Also the above concept could allow you to use the midrange above the horn in a slanted baffle to improve the time alignment without physically recessing the midrange in the baffle. 

I would not worry to much about the WinISD group delay. Anyways, you need to wait for measured FR+Phase of individual drivers in the cabinet before starting the crossover. Probably you already know that Win ISD proposes box tunings for different textbook "alignments" that seek different objectives such as lowest possible F3 etc. While WinISD calculations are correct, usually the proposed (default) boxes are too small to blend well with the LF room gain... Keep an eye on F10 as much as on F3. If I do remember well, Jeff Bagby's spreadsheet attempts to account for boundary and room pressurization gains.


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## hoovie87 (Aug 7, 2010)

dgmartin said:


> Great! Please post any findings about quantitative effects if you found something.
> 
> Besides, I was wondering if you considered using a separate cabinet for the woofers (i.e. a bass module). That would allow you to experiment with other tweeter/midrange combinations, even a conventional bookshelf actively crossed-over etc...
> 
> ...


Thanks. I ordered just two woofers and a mid so I can start experimenting on one cabinet. I havent figured out how to build it yet, however so all these ideas are welcome. I'll favor sound quality in the design then work around that for sure. I am not opposed to separate mids/highs for sure or even all three, but I hope to be able to get a good enough alignment and then build one box. What you say is tempting because I am all about dialing in the sweet spot. And of course we all know that changes with positioning in the room!!! This will be a very slow project. Next I am going to see what test equipment I want. You guys had good reccommendations above.

Regards, 
David

Sent from my Samsung Galaxy Note II


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