A CD driver on a waveguide can avoid a crossover above 1 kHz, a critical design aspect IMO. It can also provide a constant and narrow directivity, something unobtainable with a piston source. The high efficiency is nice and there is evidence that high efficiency yields "good dynamics", but all opinions for or against this are on shaky ground. JBL believes, as I do, that efficiency is key to "dynamics". Maybe they have some evidence that I have not seen.
Are you implying that the horn or waveguide would necessarily be reproducing music at higher-than-"normal" levels? Because both are directional but that comparison is obviously not worth discussing.
If a waveguide is an acoustic fire hose then I guess that direct radiator is an acoustic shower 
Some said a speaker don't sound the same near the sea than in the mountain because air's humidity (don't speak about speakers in the pool...), some fanatics (or not) said in France the sound is not the same according to the charge of the ions in air.... this is a cold shower !
Unluckily I saw many guys spending their life with expensive horns and driver like TADs for setting up their system : always something was missed : coherence, fire hose sound in a part of the band... Surmise, sure more due to horns and passive filter in relation to the easy active device we have nowadays... and certainly a lot of problems of phase !
Did i say you I heard by chance the last Avantgard avec un look à la Gedlle speakers : highs was smooth and at the same time mid bass and bass was very muddy and lasy... a grosse catastroph for an activ speaker : just the look is good in it ! Hey Earl, they copy you with a white box with a smooth touching material like tyres...
I always think than the most difficult thing with the CD is to match the good driver below it : must be fast and sounding "light" for avoid to hear the transition... I never see a design with a horn and a mid bass planar below as a transition between the CD and the heavy bass driver...
Did you see with the JBL M2 the last philosophy of monitors ? : 92 DB efficienty with 1250 watts of Crown amps ! Horn between a classical one and a waves guide and all coaxial !
Unluckily I saw many guys spending their life with expensive horns and driver like TADs for setting up their system : always something was missed : coherence, fire hose sound in a part of the band... Surmise, sure more due to horns and passive filter in relation to the easy active device we have nowadays... and certainly a lot of problems of phase !
Did i say you I heard by chance the last Avantgard avec un look à la Gedlle speakers : highs was smooth and at the same time mid bass and bass was very muddy and lasy... a grosse catastroph for an activ speaker : just the look is good in it ! Hey Earl, they copy you with a white box with a smooth touching material like tyres...
I always think than the most difficult thing with the CD is to match the good driver below it : must be fast and sounding "light" for avoid to hear the transition... I never see a design with a horn and a mid bass planar below as a transition between the CD and the heavy bass driver...
Did you see with the JBL M2 the last philosophy of monitors ? : 92 DB efficienty with 1250 watts of Crown amps ! Horn between a classical one and a waves guide and all coaxial !
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The M2 is not coaxial.
I am not surprised that Avantgard copied my designs - they had to do something!
Yes, France has some of the oddest audiophiles that I have ever run across. Audio is Zen to them.
I am not surprised that Avantgard copied my designs - they had to do something!
Yes, France has some of the oddest audiophiles that I have ever run across. Audio is Zen to them.
No ... gedlee said: JBL believes, as I do, that efficiency is key to "dynamics".
On the face of that statement ... "high SPL(efficiency)=dynamics" .... "high directivity coupled with increased efficiency = acoustic fire hose "type" delivery (on axis). I'd like a description of "dynamics" and "efficiency" about now. ...anybody? Thread is starting to read like "if -xxx- loudspeaker doesn't have horns they're not going to have dynamics". That's just BS.
Yes this is this one, a very beautifull cubist s***t !
I just don't understand how it's possible to sell it, for beginners for their loft to show to their guests ! a basic two way from Dynaudio is 10 x better !
Like some oddest audiophiles Mr Gedlee speak about... I think this is more for money than for Zen...
Well the M2 is 92 DB and it's a studio Monitor (... for Manathan's flats ?) . I have to re read, I believed the CD was a two in one ! My french....
Are there some 1" or 1.5" CD (which climb high like the little Beyma) famous for their smoothness or is it the horn which make the most of the job here with its expansion profil ? (I'm not talking about sound stage even if it can contribute to the smoothness...) : without any more driver in the highs to help it... ?
What are the 3 or 4 famous driver here between 800 hz to 17-20 k hz ?
I think Mr Gedlee poll for the one he uses, othere for the BMS 4540, any others of the same league or does it has any sense if not talked with the matched horn in the same time ?
I just don't understand how it's possible to sell it, for beginners for their loft to show to their guests ! a basic two way from Dynaudio is 10 x better !
Like some oddest audiophiles Mr Gedlee speak about... I think this is more for money than for Zen...
Well the M2 is 92 DB and it's a studio Monitor (... for Manathan's flats ?) . I have to re read, I believed the CD was a two in one ! My french....
Are there some 1" or 1.5" CD (which climb high like the little Beyma) famous for their smoothness or is it the horn which make the most of the job here with its expansion profil ? (I'm not talking about sound stage even if it can contribute to the smoothness...) : without any more driver in the highs to help it... ?
What are the 3 or 4 famous driver here between 800 hz to 17-20 k hz ?
I think Mr Gedlee poll for the one he uses, othere for the BMS 4540, any others of the same league or does it has any sense if not talked with the matched horn in the same time ?
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The link doesn't work right for me - can't see an actual speaker, so I can't comment. At any rate it was Eldam who made the claim, I don't know if it is true or not. Don't really care much either.
I am sure that I don't have to define "efficiency", just look it up.
As to "dynamics" there is no definition, only a subjective impression that many people have. Are these impressions that use the term "dynamics" all the same? - almost certainly not. "Dynamics" seems to be a word that is used to define "I like it".
At any rate we are never going to get a consensus here on a subjective term that anyone can use to mean just about anything. So, yes, maybe its best to just stay away from it and only talk about well defined objective measurements. Oh wait, that's how we got here in the first place. The claim that objective measurements don't and can't show "dynamics". So I guess we can't use objective measurements and we can't use arbitrary subjective claims - that kind of leaves us all standing around going "Well I like this." and "but I like that."
That's what was done decades ago before we understand any of the science. I'd rather not take a step backward. I'll stick with objective measurements as the only meaningful thing worth discussing.
You mean it's another of those audiophool terms like "rhythm" an "pace" and "slam" ? ? ?
Thought so . . .
But in an engineering ("objective") sense we do know what it means . . . the range over which a system output predictably (usually linearly) tracks its input (in amplitude), whether it's a flame ionization detector or a audio loudspeaker. In audio systems the dynamic range is usually bounded on the low end by system noise and on the high end by compression or clipping . . . both easily measurable and quantified. As applied to "horns" it usually means nothing more than "plays loud" . . .
The trouble with loudspeakers is that temperature changes readily alter the electrical characteristics of the voice coil amd along with it all the T/S parameters that are part of it. On top of this power compression obviously occurs as well as frequency response shifts governed by the xover (if passive) that is designed specifically around a steady state and usually cold state, impedance.
As per usual what's important is if any of these factors are going to be bad enough to actually be audible. But what is clear is that lots of things get worse (at least they drift away from the cold state designed loudspeaker) as the voice coil changes temperature.
Now unless you've designed your loudspeaker poorly, none of the changes are going to be beneficial and the only way to reduce their effects is to lower the temperature swings that the voice coil may see during normal listening. The only way to do this is to increase efficiency, so it doesn't really come as a surprise to find out that many people hear an increase in perceived dynamics when a systems efficiency goes up.
One thing's for sure though, system performance generally increases when speaker sensitivity goes up and speakers become easy to drive. Amplifiers don't have to work as hard and losses are reduced.
As per usual what's important is if any of these factors are going to be bad enough to actually be audible. But what is clear is that lots of things get worse (at least they drift away from the cold state designed loudspeaker) as the voice coil changes temperature.
Now unless you've designed your loudspeaker poorly, none of the changes are going to be beneficial and the only way to reduce their effects is to lower the temperature swings that the voice coil may see during normal listening. The only way to do this is to increase efficiency, so it doesn't really come as a surprise to find out that many people hear an increase in perceived dynamics when a systems efficiency goes up.
One thing's for sure though, system performance generally increases when speaker sensitivity goes up and speakers become easy to drive. Amplifiers don't have to work as hard and losses are reduced.
Canucks do measure spl linearity of speakers 70 vs 90dB, as published here SoundStageNetwork.com | SoundStage.com | Loudspeakers
I guess it is just a sine sweep and only some small speakers are in trouble at 90dB
I guess it is just a sine sweep and only some small speakers are in trouble at 90dB
Unless you've designed your loudspeaker poorly
, none of the changes are going to be harmful either, if present at all. And they are easy to test for. If you think you've got a bad crossover design (one that varies with load) then test if "cold" and again after five minutes of white noise at rated max SPL. If the system frequency response changes then fix the design (hardly a problem . . . the crossover should be before the transconductance stage (which should itself limit overdriving) anyway). And if you're seeing bandwidth limited compression (one driver scrunches significantly before the others, and before rated power) then, well, bad design again .For whatever it's worth I've seen no shortage of blown "high efficiency" compression drivers "in the field"
(blown while the "lower efficiency" woofers were still intact) . . . that's at least part of why they're made so easy to change out (and just another example of bad design . . . why didn't the limiters protect it? 😡). Of course in a "production environment" (where one is looking for and running continuously at 120dB+ SPLs 😱) one makes the sacrifices necessary to achieve "loud" . . . but for "hi fi" speakers in a home environment ? ? ? Really ? ? ?
If "we" define "dynamics" in this way then efficiency is the key.
Except that one of the more audible amplifier problems is its performance at low signal levels due to poor crossover distortion problems. This problem is exacerbated by high efficiency speakers.
Unless you've designed your loudspeaker poorly
For whatever it's worth I've seen no shortage of blown "high efficiency" compression drivers "in the field"
I do not accept that you can design out changes due to temperature and the system cannot be optimal at all temperatures. Lowering the temp changes is the only solution here and that means high efficiency.
Compression drivers have much smaller voice coils than LF drivers and it is the > 10 kHz signals - usually a result of heavy clipping - that heats the coil so much. By LP at 10 kHz you can save almost all of these failures, but most engineers won't do this.
Engineers who look for can be found but engineers who find can be looked for....
A lot of engineers, a lot of bad devices on HIFI... Many should be more humble, that's not what we learn at school !
To be an engineer is not a suffisant guaranty, a lot of them think they are scientists ! They is a lot of the first in the world, many less of the second !
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