# Mini statements crossover point???



## 06'Goat (Feb 9, 2009)

I am building the mini Statements:
http://www.geocities.com/cc00541/MiniStatements.html
My receiver is the Marantz SR4002 and its lowest crossover point for the fronts is 80hz.... Am I wasting these speakers midbass by crossing them over at 80hz? I have a great sub but was wondering how much different the sound would be if I crossed the minis at say 60 hz or so with a different receiver.


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## Lucky7! (Jan 7, 2008)

06'Goat said:


> I am building the mini Statements:
> http://www.geocities.com/cc00541/MiniStatements.html


The Statement family are fine speakers by all reports. Not heard any of them myself though.


06'Goat said:


> My receiver is the Marantz SR4002 and its lowest crossover point for the fronts is 80hz.... Am I wasting these speakers midbass by crossing them over at 80hz?


No. Excess unused capacity in speakers is a good thing, because they will be working less to provide the same SPL. By crossing at 80Hz instead of 60, the LF drivers will not need to excurse as far and will be lower in distortion for it.


06'Goat said:


> I have a great sub but was wondering how much different the sound would be if I crossed the minis at say 60 hz or so with a different receiver.


Based upon my own general experimentation, probably not a lot depending upon location of the speakers and sub(s). Room and set up could easily be more of an issue than the slight difference in xover frequency. However, as 80Hz is your only option, build, enjoy and don't sweat the difference. When and if you ever change AVRs and the new one has more flexibility in xover, then experiment and change it if you feel somethng else is better.

PS: a build thread with pics would be nice when you get around to making sawdust.


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## Guest (Sep 5, 2010)

Unless you already too far in to this project, I think those speakers are overkill for a 80hz crossover point. Might as well just build really good bookshelf speakers if you're going to cross that high.

Those speakers were probably meant to be run full range on their own.


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## bambino (Feb 21, 2010)

Generic said:


> Unless you already too far in to this project, I think those speakers are overkill for a 80hz crossover point. Might as well just build really good bookshelf speakers if you're going to cross that high.
> 
> Those speakers were probably meant to be run full range on their own.


I've gotta disagree with you Generic, allthough they do have 8" drivers they would benefit quite abit with some sort of crossover point. I personnally would cross them at 60hz maybe even 40hz but full range for a driver of that size is too much especially at exessive volume.:T


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## 06'Goat (Feb 9, 2009)

The mini statements that I am making have 7" woofers.


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## bambino (Feb 21, 2010)

06'Goat said:


> The mini statements that I am making have 7" woofers.


At that size, all the same, IMO:T


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## 06'Goat (Feb 9, 2009)

I have the center channel already which has the 7" woofers and it sounds great.


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## bambino (Feb 21, 2010)

I'm betting the whole getup will sound spectacular, those guys sound like they put alot of thought into there designs.:T


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## 06'Goat (Feb 9, 2009)

Ya im excited to hear the center channel with the matching mains... I have polk mains right now.


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## Guest (Sep 5, 2010)

bambino said:


> I've gotta disagree with you Generic, allthough they do have 8" drivers they would benefit quite abit with some sort of crossover point. I personnally would cross them at 60hz maybe even 40hz but full range for a driver of that size is too much especially at exessive volume.:T


Maybe at excessive volumes. It's just at the moment, it sounds like they can only cross at 80hz. I was trying to say those speakers are too nice for that. At 50 and maybe even 40hz would be better, but I think it would take some serious power to make the bass drivers in those start to distort in the first place.


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## bambino (Feb 21, 2010)

I know what your saying Generic but you may be suprised by how little power it takes to get smallish drivers up and moving. I do agree, the 40hz crossover point for them would probly be fine but full range speaker, i think not IMO.:T 

I know that the volume would be loud before the cones start moving exessively, i guess what i'm trying to get across is that full range, those speakers were not meant for as are most speakers with drivers of that size, a sub to play those lower tones is what is needed to get things sounding right. Again my opinion.:T


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## 06'Goat (Feb 9, 2009)

Generic.... do speakers overexcurse from too much power being put to them? Or because of the amp clipping? I honestly don't know.


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## bambino (Feb 21, 2010)

The more power you add or input and louder the volume goes the more the cone starts to travel.:T


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## 06'Goat (Feb 9, 2009)

So what happens when the amp starts clipping?


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## bambino (Feb 21, 2010)

Usually it means your overdriving the amp into distortion which inturn reaks havoc on the drivers even possibly the amp.:T
Someone chime in to correct me if i've got it wrong.:scratch:


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## Lucky7! (Jan 7, 2008)

06'Goat said:


> Generic.... do speakers overexcurse from too much power being put to them? Or because of the amp clipping? I honestly don't know.


Yes they can, but overexcursion is typically (and as this has been around LF drivers, I'll limit it to that) due to the driver trying to reproduce a high level low frequency signal. If for a given SPL at 80Hz, your drivers is moving 1mm, then to give the same SPL at half the frequency (1 octave lower) if needs to displace 4x the air



bambino said:


> The more power you add or input and louder the volume goes the more the cone starts to travel.:T


Same thing stated two different ways.



06'Goat said:


> So what happens when the amp starts clipping?





bambino said:


> Usually it means your overdriving the amp into distortion which inturn reaks havoc on the drivers even possibly the amp.:T
> Someone chime in to correct me if i've got it wrong.:scratch:


It's extremely unlikely to damage the amplifier.

When an amplifier clips, you get a waveform that will look like the image, generally. Minor clipping will take less off the top, really severe clipping will take off more and turn it much closer to a square wave. However, the latter sounds really bad, so than manual feedback system (you) should hear this and take pity on the gear and turn it down before damage occurs. Speaker damage of any kind is rarely an instantaneous happening and from this measurement, brief clipping is a fairly common phenomena.










Now when a sine wave is clipped it progressively becomes closer to a square wave, which has a harmonic spectrum like so....










... but because the rising and falling edges are rounded there'll be some more even order in there as well.

Any decent LF or midrange driver is going to see this input signal change as no different from the already dense harmonic structure of music or all sorts of movie sound. It will create some extra heat in the driver voice coil, but in a typical domestic environment, not enough to overheat it to the point where the V/C goes open circuit or the heat melts glues or VC formers, which is what actually happens when drivers 'burn out'. 

In some instance, depending upon the HF driver, xover, power and signal, some tweeters do not like clipping and _may_, be damaged, especially if the clipping is severe. This was far more common in the 70's, but _far_ less so with modern drive units. It is a hang over of information passed on without context taken as fact, that drivers are easily damaged by clipping.

>

The discussion has segued far from the original intention of my comments early on regarding distortion. What I meant then was not that having two LF drivers in the SM would reduce likelihood of damage (side benefit at best), but that in general use, distortion would be lower, both from having 2 drivers (vs 1) and using a higher xover.

A loudspeaker driver is a motor, and a low signals it is very linear and there is very little distortion. As the driver is called upon for more SPL it needs to excurse further to move more air (SPL is proportional to the _volume_ of air displaced). The further from rest it moves, the more distortion increases because the motor and suspension become less linear with increasing travel. Cone travel also increases with decreasing frequency (4x more for each octave lower).

When speaking of distortion most people think of THD and what happens when a sine wave is applied and distortion is measured. There is another type of distortion called, IMD or Inter Modulation Distortion which is far more relevant. 

When just two sine waves are used as the signal in a non linear system, such as a speaker motor with more than a bit of it's excursion being used, creates extra non harmonically related signals. Below shows what happens when two signals F1 and F2 are introduced.










Music/movie sound is a very complex signal, full of all sorts of harmonic and other information from the various sounds that make up the soundtrack and may make up many hundreds or thousands of components, so if the above is what happens with just two, can you imagine what happens with more?

So lowering driver excursion for the reasons I mentioned has advantages, that are audible. The original question was "Am I wasting these speakers midbass by crossing them over at 80hz?" and I've answered why I think not. If you can afford the parts, and they aren't physically too large, then they make a good choice based upon a competent design and user feedback. Are you wringing every bit of sound out of them you can at 80Hz vs 60Hz? No, but there isn't a lot in it. This I see as overtaking horsepower: you might only need 50bhp to drive the freeway at the posted limit, but when you need to overtake or come to a hill, the extra 30 you have spare make the journey more pleasant. Same applies here with peaks sounding cleaner/more effortless and having a bit left in reserve for those large peaks and the time you want to turn it up a bit.

As for the second question "I have a great sub but was wondering how much different the sound would be if I crossed the minis at say 60 hz or so with a different receiver", not much from the MS themselves, but the sub capability, placement in your room and how well you set them up could likely be a much larger difference than a slight change in xover frequency.


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## bambino (Feb 21, 2010)

WOW! Thank you for the clarification and knowledge A9x, i love this site, always learning new stuff.:T


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## 06'Goat (Feb 9, 2009)

Thanks A9X very informative!


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## dwisner (Nov 7, 2010)

I have the big "Statements" mains, and I have them crossed at 80. They sound great. I'm building a new set of larger ported subs and may cross them a little differently when finished.


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## Jim Holtz (Feb 18, 2009)

Hi Guys,

I'll throw out my perspective on this. Curt and I designed all the Statements series speakers to excel at music with enough dynamic response to reach reasonably high volumes comfortably. You can expect Mini's to handle 105-110+ db peaks easily. Now comes the real question. How loud to you want to play them? Figure about a 20 db swing on well recoded music. If you're listening at 90 db in a normal sized room they'll easily handle those dynamic peaks. 

I assume most here are also using them for home theater and running a sub. Music requires accurate bass. Home theater requires LOUD bass and shaking power. If you listen to hip hop , pipe organ or some music that you want to shake the room with, a sub is required. If you want to listen to music with normal bass, a sub won't add much IF you're trying to listen to it accurately. I do not have my sub on when listening to music with any of my Statements (I have them all) but I do roll a sub in when using them for home theater. I'm a jazz and blues fan so over powering bass is not usually part of the mix. Good clean solid deep bass is. 

However, I run all of my Statements series speakers full range. I base my home theater volume on voices during speech passages and adjust the volume to a comfortable level. I let the bass take care of itself. If it's there, it'll shake the room. It won't shake anything if it's not there to start with. If you want to get crazy with the volume control I'd suggest you cross to a sub(s) around 60 Hz with a 24 db crossover. That way you can still enjoy accurate bass in the upper and part of the mid bass. 

HTH

Jim


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## Theresa (Aug 23, 2010)

It doesn't do any harm to crossover at 80Hz, or 60 if you must. Subs can handle 80Hz a lot better than an 8" intended for midwoofer duty. I know my ScanSpeak 7" midwoofer, my center, "can" go down to 40Hz and can handle 11mm physical xmax (one way) I still will cross them over at 80Hz. Theres no real directional information at 80Hz, that's why it became the standard. I have mine setup for 90Hz at the moment since I have Eton midwoofers in my L/R which can't handle much excursion but the ScanSpeaks (to match my center) are on the way and I'll be setting it back down 80Hz as soon as they are installed. I use two subs so 90Hz isn't "pulling" the image over to one side and I cannot hear any deviations in imaging. I also don't believe in a speaker having "speed." Low frequencies are by definition "slow" whether from an 8" or a 15"


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## Guest (May 11, 2011)

Theresa said:


> It doesn't do any harm to crossover at 80Hz, or 60 if you must. Subs can handle 80Hz a lot better than an 8" intended for midwoofer duty. I know my ScanSpeak 7" midwoofer, my center, "can" go down to 40Hz and can handle 11mm physical xmax (one way) I still will cross them over at 80Hz. Theres no real directional information at 80Hz, that's why it became the standard. I have mine setup for 90Hz at the moment since I have Eton midwoofers in my L/R which can't handle much excursion but the ScanSpeaks (to match my center) are on the way and I'll be setting it back down 80Hz as soon as they are installed. I use two subs so 90Hz isn't "pulling" the image over to one side and I cannot hear any deviations in imaging. I also don't believe in a speaker having "speed." Low frequencies are by definition "slow" whether from an 8" or a 15"


80hz isn't obvious, but I wouldn't say its no directional at all. If it wasn't then sub placement wouldn't be so important, and neither would having two subs next to the mains, compared to just one sub.

I myself only have one sub, and it's placed between the mains. Any other place and I find the sub does not blend as well.


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## Theresa (Aug 23, 2010)

Extra excursion is never wasted, it results in lower THD and IMD. I think 80Hz will be just fine and lets the sub do what it's designed for.


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