not at all denying what the Dr. is saying, but help me here...
could it be that the differences some seem to be hearing in the exact same setup comparing two woofers for example are due to differences in FR that are very small say 1 db or less? Could it be that although we may say two drivers measure very close and call that the same FR, that "very close" is simply not close enough?
could it be that the differences some seem to be hearing in the exact same setup comparing two woofers for example are due to differences in FR that are very small say 1 db or less? Could it be that although we may say two drivers measure very close and call that the same FR, that "very close" is simply not close enough?
What is the meaning of "vivid"? Horns are definitely more dynamic than direct radiators owing to their high efficiency - sometime as much as 20 dB greater than a dome tweeter. And they have far better directivity control than a piston source. Does this make them more "vivid"? I don't know, I don't know what "vivid" means in objective terms.
Yea, dispersion isn't as much of an issue with woofers but eq'ing two drivers exactly the same is difficult. Also there will be nonlinear distortion especially with greater excursion that someone might pick up on.
That's possible, just as its possible that people are hearing a difference that isn't really there. It takes a serious experimental design to sort out which is a fact and to what degree.
Most carefully done studies have shown that the later explanation - mine - is the more common. We listen hard to hear differences - to the point that we create them. I have seen this myself so many times that it is just what I have come to assume to be the case. But that doesn't mean that it IS always the case. But to assume that it is never the case is simply ridiculous.
I don't know other than to say that it seems like I can feel the sound, even at lower volumes.
I have never seen two drivers measure “exactly” the same either. Certainly would like to see any CSD data that others may have measured to be the same regardless what scale they are viewed in. But I do agree that some may seem the same and sound different, which when zooming in closer might show some difference.
Maybe piston drivers enter into distortion when there are brief spikes in volume. This could explain some of what seems like "vividness", which begs the question whether some of the overbuilt drivers really do perform better in small ways.
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Wow... Dr Geddes has perfected drivers...!!
Point by point...
(1) Correct, I declared that drivers are imperfect. Fact, they are imperfect.
(2) You claim to have "perfected driver" design... Hmmmn, I just lost faith in your opinion... Can you post the link to your design of perfect drivers?
If you referring to the standard bass mid drivers, passive crossovers & compression drivers you load with your design of horn no need to bother.
(3) You claim your designs are "solutions for the real world"
How many pairs have you sold? Real world solutions mean you you are competing with mainstream companies... If you have perfected a real world solution you must have a website displaying 100's or even 10's of delighted customers....
I have been following your posts and website for over 10 years and yet to see any evidence of sales beyond a few niche audiophile reviews. Enough said.
(4) Avantgard, Cessaro, Oswalds Mill etc... All specialist horn loudspeaker manufactures, they all regard large expensive horn loudspeakers as low volume niche solutions for the 0.01% population...They also have websites displaying their sales, typically less than 1 high end sale per month according to their news / blogs.
So, I think its clear that your claims are false.
Your opinion of real world solutions is distorted.
Your bias towards promoting your own horn design (not driver design!) with or without the fish tank foam stuffing is blinding you to whats happening in the real world of modern audio design.
Point by point...
(1) Correct, I declared that drivers are imperfect. Fact, they are imperfect.
(2) You claim to have "perfected driver" design... Hmmmn, I just lost faith in your opinion... Can you post the link to your design of perfect drivers?
If you referring to the standard bass mid drivers, passive crossovers & compression drivers you load with your design of horn no need to bother.
(3) You claim your designs are "solutions for the real world"
How many pairs have you sold? Real world solutions mean you you are competing with mainstream companies... If you have perfected a real world solution you must have a website displaying 100's or even 10's of delighted customers....
I have been following your posts and website for over 10 years and yet to see any evidence of sales beyond a few niche audiophile reviews. Enough said.
(4) Avantgard, Cessaro, Oswalds Mill etc... All specialist horn loudspeaker manufactures, they all regard large expensive horn loudspeakers as low volume niche solutions for the 0.01% population...They also have websites displaying their sales, typically less than 1 high end sale per month according to their news / blogs.
So, I think its clear that your claims are false.
Your opinion of real world solutions is distorted.
Your bias towards promoting your own horn design (not driver design!) with or without the fish tank foam stuffing is blinding you to whats happening in the real world of modern audio design.
I don't think he did, at least that's not how I understand what he said in the post you quoted.
The reason I go here is not to defend any position of belief some seem to have. And I have little doubt that you are right about much if not all of what you are fighting for here.
My problem is my experience in this one example. I have three ribbon diaphragm designs in development as we speak. These are all same size, mass, impedance, wave guides box and box stuffing etc etc.. Only the diaphragms are different and the 3 different ribbon constructions have been manipulated to get same FR within +- 1db from 1k to 20k , and CSD of all shows no tails and all is down 30db by about 1.5 ms.
Only difference is the diaphragm constructions wich range from a foil only , a plastic backed composite, and a 2 layer foil constrained layer.
These are all placed together on top of a woofer module in a triangle shaped enclosure of equal sides on a turntable with a lamp shade like screen around all to hide them from view. This way each can be turned into place in seconds and the listener does not know which they are listening to.
In front of each ribbon, on the screen are stick on letters A,B,C. The units are set up and my wife puts the letters on. I listen and write what I think I hear. Same tracks over and over. Drives her nuts! Then I get up and look to see what ribbon is where and compare to notes. I then have her change the positions of the A B C stickers and do it again. and again.......
Heres the deal, it has become fairly easy to get a consistent review of the three. The composite and the constrained layer versions have more error in conclusion. There hard to tell apart and interestingly they are similar builds, BUT the foil only version is easy to hear.
With FR and CSD looking so similar what is it Im hearing? Theres enough consistency to lead me to believe Im not making it up.
This thread is supposed to be about real world drivers, not ones in someones mind.
If the diaphragms aren't exactly the same size, then you would different dispersion, not to mention slightly different frequency response and nonlinear distortion.
Hmm the diaphragms are exactly the same size, just different constructions.
The FR are within +- 1db of each other. Maybe thats enough to notice?
In the distortion dept. they ALL show close to same basic profile and all below .3% at 95db.
I measured the horizontal dispersion's and all 3 look very close if not spot on. Vertical I dont know, there all 100mm long by 20mm wide.
The only obvious difference I see in measurement is the foil only version is 2 db more sensitive (adjusted in test to be same however), than the other two that are carrying some dead weight in the form of plastic and/ or adhesives and interestingly enough this foil only version I often characterize as sounding, well, more dynamic.
Would we think that 2 db increase in sensitivity is the primary reason for the noticeable difference? I have no frame of reference for such a judgment.
1 db over a wide enough area is easily noticeable, If your really curious you could EQ the difference away and then do a blind test.
yes I am painfully aware of the audibility of even 1 db over large area. However in this case that +-1 db are just short small sharp wiggles around in the 5-8 khz range.An area of trouble in many ribbon constructions of these widths.
When u lay the FR's on top of each other they are less than 1/2 db deviation 1k to 15 k with the foil only having a 1 db edge over others from 15 to 20 k.
When u lay the FR's on top of each other they are less than 1/2 db deviation 1k to 15 k with the foil only having a 1 db edge over others from 15 to 20 k.
lowmass if they are with 1/2 a db of each other and you can still distinguish/perceive a difference that you can readily indentify that's amazing.
can i ask what the max deviation across the stated banwidths are?
can i ask what the max deviation across the stated banwidths are?
Nothing in this world is perfect, all the discussion is about getting it closer to perfection. I think Dr. Geddes has made lots of contribution to this effort. Everyone has there own view on the design tradeoffs involved which may be different, and sales is not a way to measure success. You can increase sales numbers by putting in the marketing investment which quite often exceed cost of technology development.
Horns are great, as a matter of fact I have heard some good aspects while listening to a pair of Avantgarde Trio which was an inspiration of what improvements in loudspeakers can be possible. Dr. Geddes’s speakers have a disadvantage in sales not because of technology, but looks. Most people do not think about designing a room around speakers, but rather want the speakers to have a more decorative statement.
Something that doesn't seem to get mentioned, or maybe its just that I've been oblivious to it, is that as the volume of a source goes up, so does the difference between the loudest and softest parts.
So you can never really have dynamics without volume. At low volume there is always less of a difference between the loud points and silence.
So horns might just sound more vivid because in a larger room they naturally play at a larger dynamic range (at a given perceived volume) so they sound more vivid and lifelike than a small speaker in a small room. The bigger room reverberates the louder sound and creates the sense of depth. This is why something like a train even at a distance sounds very powerful.
So dynamics is just related to scale. It never occurred to me that sound changes nonlinearly when the volume goes up.
So you can never really have dynamics without volume. At low volume there is always less of a difference between the loud points and silence.
So horns might just sound more vivid because in a larger room they naturally play at a larger dynamic range (at a given perceived volume) so they sound more vivid and lifelike than a small speaker in a small room. The bigger room reverberates the louder sound and creates the sense of depth. This is why something like a train even at a distance sounds very powerful.
So dynamics is just related to scale. It never occurred to me that sound changes nonlinearly when the volume goes up.
I think it's more down to their directivity. Re dynamics, the limits of perception section here may help Psychoacoustics - Wikipedia
Ears/brain will adjust to level
There are some things I have noticed is that when you have good low frequency reproduction, normally below 40Hz, the sense of dynamics increase.
Larger rooms delay reflections longer, so I assume it would present a better sense of depth, although I have also noticed that linear phase increases sense of depth as well. Correct polarity also contributes to sense of depth. Faster decay shown in CSD helps preserve original recording timbre and reflection delays so you also get be better sense of image depth.
Larger rooms delay reflections longer, so I assume it would present a better sense of depth, although I have also noticed that linear phase increases sense of depth as well. Correct polarity also contributes to sense of depth. Faster decay shown in CSD helps preserve original recording timbre and reflection delays so you also get be better sense of image depth.
I've noticed this as well, the sub reduces cone excursion which reduces cabinet noise and also nonlinear distortion.