I beg to differ. The modern KEF Uni-Q coaxials for example, may be some of the best drivers out there, period, both tweeter and midrange. The BMS units are also very good.
Reaching a tweeter is also not an issue as the boost provided by the 1pi space of the coaxial cone reduces power handling demands. A ~1.2khz crossover frequency is very doable as long as you cut off moderately steep and don't use too ringy a cone.
Rock,
We will have to differ. I have a set, and think very little of them. Their crossover is not smooth or free is issues and they don't image any better than my own conventional designs.
1.2K is way too high for any 10 I have seen due to mass, beaming, and breakup modes. I have never found a tweeter whose distortion is usable below 1.6 and that is 4th order. Yes, we hope the cone works like a horn to improve the efficiency and lower distortion, but somehow it does not quite deliver on that promise. Just like we hope the acoustic center is the same, and we don't get off axis interference issues. All great ideas. All not quite delivered. I keep hoping.
Win,
Why do they make bigger? You make what you can sell. They made and sold Yugo's too.
We will have to differ. I have a set, and think very little of them. Their crossover is not smooth or free is issues and they don't image any better than my own conventional designs.
1.2K is way too high for any 10 I have seen due to mass, beaming, and breakup modes. I have never found a tweeter whose distortion is usable below 1.6 and that is 4th order. Yes, we hope the cone works like a horn to improve the efficiency and lower distortion, but somehow it does not quite deliver on that promise. Just like we hope the acoustic center is the same, and we don't get off axis interference issues. All great ideas. All not quite delivered. I keep hoping.
Win,
Why do they make bigger? You make what you can sell. They made and sold Yugo's too.
Not quite the transparency of the Hiquphon tweeters on my other system, but more coherent (despite having the crossover point where the human ear is most sensitive, in contrast to the extended midrange concept in my other system). Amazing is that the 10" woofer section has no beaming whatsoever at 2 kHz. The polar response at 20 kHz goes up to about 45° , also more than one would expect from a 1"er.
I agree with you on that. KEF's crossover is pretty half-assed.
The point of a coax isn't imaging, it's a wide sweet spot and even, controlled power response.
Not sure what you mean by mass.
Beaming is not a concern. At around 1.2 you will have a roughly 120 to 90 degree radiation and it will also guide the tweeter radiation with the same pattern. This is not beaming.
Breakup is the real concern. Audible breakup is probably a necessary evil, as a good 10" woofer will be in breakup above 2khz. Some breakup is pretty benign though, like the Acoustic elegance cones for example.
If that's the case, then tell me the likely crossover point of the following graph:
...it's a Dayton RS28F dome tweeter crossed over at 1khz, with 10W input
By mass, mass of the cone. That has pretty severe limitations on HF output. That is why great big honking subs frequently can't reach much over 100 Hz. I like my 830500's because they will work as high as 200, but still get me the low 30's I want. A nice light 10, should be good to 500 to 700 if the breakup is high enough, or damped well enough. If it is light enough to make it up into the low K's, then it just won't have the mass or the voice coil to make it into the bass.
Just because you can do a frequency chart showing how low a tweeter will go, does not mean I would ever want to use one there. DISTORTION is the problem. The larger ( 1 1/8) Dayton may have an advantage on the lower end to most 1" drivers, but I still would not use it that low. It is a reasonably well respected unit. It has lower frequency breakup issues to match the larger size and higher mass. Depending on your hearing, they may still be out of range so it could serve you well.
I can't comment on your graph as I don't know how it was made. Small differences in method make very large differences in the graph. An inch difference in mic position, a ms or so in gating, resolution, post processing. If I made your chart, I would probably think it was a tad on the bright side. My measurements need only be consistent to me so I can relate them to my experience. My charts would be just as meaningless to you as yours are to me.
Everyone has different sensitivities. Low treble distortion seems to bother me and my wife more than it does others. Even though I am an old fart, I seem to still have quite extended HF range, though my discrimination is decreased from 30 years ago. I seem to be more sensitive to bass unbalance than when I was a young whippersnapper. Too loud bass really bothers me.
You are admitting a 10 inch will have breakup issues as low as 2K. That is WAY too close for me for a 1K crossover even at 4th order. 500 would be a far more appropriate crossover. Maybe you could pull it off with an active crossover. Could be cheaper too considering the cost of copper these days.
As I said, it is not the concept I disagree with. It is the execution.
JRKO,
Yea, I remember the big Tannoy's from days past. I have not seen one in a store in the last 30 years. The Washington D.C. metro area is not noted for hi-fi.
el'
I'd like to try some Hiquphon's, but have not found a mid-base that can push to 4K or so where I would want to cross them over. Going three way has not had good results for me. It could be my crossover skills are not there yet. I really hate to go down to 2500 or so. I rather put my crossovers further to the edges of the critical sensitivity range. I am going to order some anyway. They don't measure that great, but owners seem to be very fond of them. I see Linkwitz has latched onto the Seas woven poly midwoofers. As they are pretty light and breakup pretty well damped, maybe, just maybe the smaller one......
Just because you can do a frequency chart showing how low a tweeter will go, does not mean I would ever want to use one there. DISTORTION is the problem. The larger ( 1 1/8) Dayton may have an advantage on the lower end to most 1" drivers, but I still would not use it that low. It is a reasonably well respected unit. It has lower frequency breakup issues to match the larger size and higher mass. Depending on your hearing, they may still be out of range so it could serve you well.
I can't comment on your graph as I don't know how it was made. Small differences in method make very large differences in the graph. An inch difference in mic position, a ms or so in gating, resolution, post processing. If I made your chart, I would probably think it was a tad on the bright side. My measurements need only be consistent to me so I can relate them to my experience. My charts would be just as meaningless to you as yours are to me.
Everyone has different sensitivities. Low treble distortion seems to bother me and my wife more than it does others. Even though I am an old fart, I seem to still have quite extended HF range, though my discrimination is decreased from 30 years ago. I seem to be more sensitive to bass unbalance than when I was a young whippersnapper. Too loud bass really bothers me.
You are admitting a 10 inch will have breakup issues as low as 2K. That is WAY too close for me for a 1K crossover even at 4th order. 500 would be a far more appropriate crossover. Maybe you could pull it off with an active crossover. Could be cheaper too considering the cost of copper these days.
As I said, it is not the concept I disagree with. It is the execution.
JRKO,
Yea, I remember the big Tannoy's from days past. I have not seen one in a store in the last 30 years. The Washington D.C. metro area is not noted for hi-fi.
el'
I'd like to try some Hiquphon's, but have not found a mid-base that can push to 4K or so where I would want to cross them over. Going three way has not had good results for me. It could be my crossover skills are not there yet. I really hate to go down to 2500 or so. I rather put my crossovers further to the edges of the critical sensitivity range. I am going to order some anyway. They don't measure that great, but owners seem to be very fond of them. I see Linkwitz has latched onto the Seas woven poly midwoofers. As they are pretty light and breakup pretty well damped, maybe, just maybe the smaller one......
that graph shows the distortion. It shows that it is not a problem at all.
You would be wrong. Mass is barely at all an issue. If you reduce and linearize inductance you can get very good extension even out of heavy cones.
It appears he skipped right over post 27.
An excellent example are AE drivers: https://sites.google.com/site/drivervault/driver-measurements/tang-band-75-1558se/ae-speakers-td12m
Au contraire! 10 is too small. 15 or 18 is much better, you get a better horn.
(Yes, I've heard coaxes from 8 to 18 inches) IME, the bigger the better.
What???
Sorry, but you're just randomly using the word "physics" to justify an opinion.
I know I know, just can't physically fit them...this is for the car. 10s are about as large as I can get up front.
I have space for my commercial autosound horns and 6s, 8s if I cut the floor. Or 10" coaxes. I have Audax pr17mos and 18sound 6nd430s, and love the audax, but big mids make me happiest.
It has been 20 years since I've had coax drivers like these...long before I knew good sound, which is why I was wondering about the hf modulation.
I have space for my commercial autosound horns and 6s, 8s if I cut the floor. Or 10" coaxes. I have Audax pr17mos and 18sound 6nd430s, and love the audax, but big mids make me happiest.
It has been 20 years since I've had coax drivers like these...long before I knew good sound, which is why I was wondering about the hf modulation.
Yes, a substandard implementation like your old base-model KEFs will have problems.
That's not news to anyone, and doesn't really tell us much beyond "poorly optimized designs often don't work that well.
Some of the newer ones are quite a bit better, because of the redesigned phase plugs, and new tweeters that have the cone area and volume displacement to play low enough to actually match the woofer's directivity. Incidentially, the new base-model KEF, Q100, is a lot better than the next-model up, Q300. The reason is that the Q100 maintains its midrange pattern, and based on my listening experience with the Q300 it has the telltale midrange colorations of a mushroom-cloud midrange pattern.
Au contraire! 10 is too small. 15 or 18 is much better, you get a better horn.
(Yes, I've heard coaxes from 8 to 18 inches) IME, the bigger the better.
I disagree with that. Yes, a very big driver can maintain its pattern lower, but I've not heard a 15" concentric driver with a woofer good enough to play up to the crossover region. To my ears, for instance, the old Tannoy System 15 DMT II, Churchill, and Glenair (15") were rather colored in the lower mids compared to the Tannoy System 12 DMT II (12"), D700 (10"), or Glenair 10 (10"). So it seems to me that, for a narrower-pattern system 10" or 12" might be the sweet spot.
For a wider-directivity system, I think it's interesting that all of the serious, engineering-driven commercial home speaker companies (Revel, KEF, TAD/Pioneer, etc.) right now are more or less standardizing on 5" midranges and relatively higher transitions from omnidirectional to ~120deg patterns in the midrange. Not sure what that means (current fad, or what) but it's worth noting.
Guess it depends what you want to do. The best coax drivers I've heard (and built crossovers for) are 15" or 18". But 10 or 12 can work, too. Great as a midrange with a helper woofer, which is what Winslow is doing, right?
It gets to be a balancing act. Is the woofer cone big enough to allow the horn driver to work down into a range that will cross well with the woofer cone? Will the woofer play cleanly up to the point where to horn has to be crossed? Some do, some don't. Some coax drivers with a small horn in the center (Altec, for example) have spillover into the cone from the small horn. That can actually help.
Those are the sort of issues I see when working with coax drivers.
It gets to be a balancing act. Is the woofer cone big enough to allow the horn driver to work down into a range that will cross well with the woofer cone? Will the woofer play cleanly up to the point where to horn has to be crossed? Some do, some don't. Some coax drivers with a small horn in the center (Altec, for example) have spillover into the cone from the small horn. That can actually help.
Those are the sort of issues I see when working with coax drivers.
Jay, thanks for the model numbers of the Tannoys that use 10s. I will keep my eye out for some of those. The kef 8s at Speaker Exchange look interesting, just have to be creative on mounting them.
Yeah, not trying to get down in the 20s with the drivers. Have a nice sub that can play as high as I need it to.
Yeah, not trying to get down in the 20s with the drivers. Have a nice sub that can play as high as I need it to.
The least expensive option for you if you take apart an existing Tannoy would be the old Saturn S10 or System 1000 studio monitor. (System 10 DMT II would be next-cheapest, and probably easier to find. Gotta be careful not to get stuck with the System 10 DMT, though; the Tulip phase plug and I think different compression driver are a lot better than the earlier model's bullet phase plug.)
Also, that would be the least loss, as the Saturns were their day's equivalent of today's KEF Q-Series: great drivers, penny-penching cabinets. By contrast, it would be a shame to dismantle a D700 or Glenair for the Duals, unless the cabinet were beyond repair.
The TD10 is another option, pretty cabinet but so-so sound at best. I've found that the paper-cone big Duals just don't do it for me like the poly-cone ones do. Though perhaps the blame really goes to that stupid supertweeter rather than the Dual itself.
As for the KEF Q900 drivers on the Speaker Exchange site, at least as of a month ago they were out of stock, with no concrete ETA. If you end up thinking that 8" Duals might work for you and want to get your hands on some, lemme know, because I have a few just sitting around.
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