On topic:
One of the best midranges i heard so far were from JBL 2202H (Mms 50gr, Le - 1,1mH) xovered at 1,2KHz and JBL 2122H xovered at 1,3KHz. A bit better than JBL 2202H was JBL E120 reconed with 2202H recone kit - but JBL purists would never do that - luckily the guy i listened it at is not one of them so we were able to listen them side by side and compare.
Speaking of differences between two large format drivers that are declared BASS and MID - did you ask yourself what are the parameters that makes one speaker mid duty or plain bass ? When i did, i looked at it and saw that low Le and low Mms are crucial for a good midrange as was later confirmed by listening test. I made few 12" two way speakers that had xover frequencies quite high (arround 1,5KHz) and they sounded good but they were low mass and had low coil inductivity (Mms- 39 and 37 gr and Le 0,8 and 0,43).
I would not describe the sound of large driver with heavy cone "lazy" and that it lacks "attack" from 400 to 1KHz - i would say that it lacks the details that are revealed by small format midrange or the same format driver that is made as dedicated midrange.
One of the best midranges i heard so far were from JBL 2202H (Mms 50gr, Le - 1,1mH) xovered at 1,2KHz and JBL 2122H xovered at 1,3KHz. A bit better than JBL 2202H was JBL E120 reconed with 2202H recone kit - but JBL purists would never do that - luckily the guy i listened it at is not one of them so we were able to listen them side by side and compare.
This thread originally started as my inquiry into speaker measurements but quickly evolved into another interesting discussion, thus I overhauled this first post and moved my questions elsewhere:
so, for those "who like it BIG"the NEW TOPIC is:
>Does the size and mass of the cone driver matter when it comes to mid duty?
>Does a large and heavy cone sound "lazy" and lack "attack" subjectively (for example a 12 incher if used up to say 1kHz)?
How about the difference between the same large size drivers but one meant for bass and the other exclusively declared by manufacturer as "mid duty" (like those from PD for vocal stage monitors for example)?
...and more questions are wellcome if along these lines
Bask in difference of opinions and enjoy
Speaking of differences between two large format drivers that are declared BASS and MID - did you ask yourself what are the parameters that makes one speaker mid duty or plain bass ? When i did, i looked at it and saw that low Le and low Mms are crucial for a good midrange as was later confirmed by listening test. I made few 12" two way speakers that had xover frequencies quite high (arround 1,5KHz) and they sounded good but they were low mass and had low coil inductivity (Mms- 39 and 37 gr and Le 0,8 and 0,43).
I would not describe the sound of large driver with heavy cone "lazy" and that it lacks "attack" from 400 to 1KHz - i would say that it lacks the details that are revealed by small format midrange or the same format driver that is made as dedicated midrange.
Last edited:
I'm not implying there's a breakup of significance in your designs. If you cross low enough and steep enough, or use a notch filter all is good. As I said earlier, they're great designs. Once introduced to a similiar speaker whose one and only crossover point was below 1khz, my design philosophy changed for the better, and for good!
But I gotta draw the line here......
........ I can't see how you can state that measured harmonic distortion can be anything BUT objective? Without being purposely insulting, that sounds just plain silly.
That JBL monitor - a really great speaker - actually throws a much wider pattern than Dr. Geddes targets. It's worth nothing that their bespoke 12" woofer has fairly early breakup. The factory spec sheet is available at Lansing Heritage.
Yes, the measurement of THD is objective, just not relevant. Like the skin effect in speaker wire. Sure it exists, but so what. It is the audibility of that nonlinearity that is subjective. It has never been shown to be audible. It exists, sure, we just can't hear it.
Last edited:
both JBL 6332 and Earl's designs are good for corner placement, keeping dispersion under 90deg for managing early reflections. as monopoles I imagine both should share the stage of the "they are there" type. I listened to Earl's Summas at his home and I appreciated the different feel of the "sound curtain" staying at a distance in the front and not getting closer. I expect the dipole version, (and I have two such in the works but they will take time), should be quite different of the "they (musicians) are here" type. I actually would not mind having both types of setup at home (to suit the mood of course ).
what the large size woofer in Earl's design brings I think is what you see in his FR plots, starts as a BBC dip (1 to 3 kHz), recovers at smaller angles and then it does not recover any more, so the beam effectively starts at lower frequencies. this I think will make some vocal material (like Diana Krall which he likes auditioning) sound very good. a typical comment from his custommers though will be about the speakers sounding dark or lacking air. I would love to hear the difference to JBL where the curves plot as pretty flat to 5kHz. in the end, as always, it probably boils down to personal taste and what program you are listening to.
).what the large size woofer in Earl's design brings I think is what you see in his FR plots, starts as a BBC dip (1 to 3 kHz), recovers at smaller angles and then it does not recover any more, so the beam effectively starts at lower frequencies. this I think will make some vocal material (like Diana Krall which he likes auditioning) sound very good. a typical comment from his custommers though will be about the speakers sounding dark or lacking air. I would love to hear the difference to JBL where the curves plot as pretty flat to 5kHz. in the end, as always, it probably boils down to personal taste and what program you are listening to.
Have you or someone else confirmed this? There are some other speaker designers claiming this. But I have not seen any serious attempt to prove it…..
Btw, are we talking about from lower midrange and up?
Peter
Last edited:
I studied this problem for decades and have several publications on the perception of nonlinear distortion. Several others have followed suite since I stopped looking at this (because it turns out not to be a significant issue), and at every turn we have all concluded the same thing - it simply is not an issue in a loudspeaker.
The bottom line is that nonlinearities in loudspeakers, while the numbers can be very high, are just not likely to be an issue. (I should poi9nt out that I CAN make them an issue, but I CAN also make them irrelevant and that is the point.) That is not the case for electronics however, where some types of common nonlinearities can be quite audible.
Bottom line here is that this issue has been studied enough to know that it does not warrant further study for loudspeakers. Nonlinearity of the drivers is not what we hear in a loudspeaker. There are things that we hear and they sound like "distortion" but they are linear and as such don't appear as THD.
both JBL 6332 and Earl's designs are good for corner placement, keeping dispersion under 90deg for managing early reflections. as monopoles I imagine both should share the stage of the "they are there" type. I listened to Earl's Summas at his home and I appreciated the different feel of the "sound curtain" staying at a distance in the front and not getting closer. I expect the dipole version, (and I have two such in the works but they will take time), should be quite different of the "they (musicians) are here" type. I actually would not mind having both types of setup at home (to suit the mood of course
what the large size woofer in Earl's design brings I think is what you see in his FR plots, starts as a BBC dip (1 to 3 kHz), recovers at smaller angles and then it does not recover any more, so the beam effectively starts at lower frequencies. this I think will make some vocal material (like Diana Krall which he likes auditioning) sound very good. a typical comment from his custommers though will be about the speakers sounding dark or lacking air. I would love to hear the difference to JBL where the curves plot as pretty flat to 5kHz. in the end, as always, it probably boils down to personal taste and what program you are listening to.
I would caution that I would not recommend my speakers be put in a corner. They are designed to be "free field" and corner placement would add issues that they are not designed for. That said, I would never put any speaker in a corner. It is just not a good idea.
Actually no customer has called the speakers "dark", but I have heard "bright". In my setup the treble is down by about 3 dB because, to me, that sounds "neutral". Measured "flat" response to HFs is almost universally thought to sound bright. So they don't "sparkle" or "sizzle".
It also depends on what you are used to. People who listen to 1" dome tweeters become used to a particular sound which is rich in the direct field but with no reverberation at all (due to beaming. Maybe this is what you call "air". When you listen to HFs that do not beam there is an entirely different sense - but I won't attempt to give it an adjective, I'll stick with the polar plot descriptions.
The problem with loudspeaker auditions is "acclimation". We all get acclimated to what we listen to and everything else gets judged against that personal standard. Once you get acclimated to something that measures as good as possible then you have a standard that is neutral and all else sounds lacking. It is the realization of this effect that caused me to stop showing at audio fairs. Short term auditions are simply flawed, there is no way around it, except to acknowledge this flaw and pay primary attention to the objective data. That is the only way to move forward.
This idea that our ears are good judges is simply wrong. I am sorry for having to take this position, but it is one that I have come to after nearly 50 years in this business. I wish that I were wrong, I fear that I am right.
You cannot understand how bad I find virtually all other loudspeakers that I listen to. Maybe I have come to be "acclimated" to my own speakers, but I know this, I have become acclimated to speakers that do not have objective flaws, at least I can be certain of that.
Harman has proved this time and time again, that in blind tests the speaker that measures best gets rated best. Un-blinded - the results will be completely different. I am not going to argue with those results.
That would be me, but I don't have these speakers.Isn't there a prolific psychopath from this forum in or near Portland?
Hey Earl, here is a piece which measures and reports about the "doppler distortion" in loudspeakers. Are you saying that while such distortion is measurable, it is still insignificant?
Doppler Distortion in loudspeakers
I have Lowther drivers and I once made a change to high pass them (at about 80 to 100 hz) instead if using them full range. Afther the change highpassing the Lowther drivers the midrange was clearer (less congested).
If the change in distortion is insignificant, then do you have a sense of why I heard an improvement in the midrange frequencies? Is it an electrical phenomonen in the driver or could it be due to the cone material being less compromised when the bass was kept out of the driver? This could be an improvement in the amps too since I used a smaller coupling capacitor between the driver tube and the output tube of my SE amps, which means that the output tube is not trying to reproduce deep bass.
Retsel
Doppler Distortion in loudspeakers
I have Lowther drivers and I once made a change to high pass them (at about 80 to 100 hz) instead if using them full range. Afther the change highpassing the Lowther drivers the midrange was clearer (less congested).
If the change in distortion is insignificant, then do you have a sense of why I heard an improvement in the midrange frequencies? Is it an electrical phenomonen in the driver or could it be due to the cone material being less compromised when the bass was kept out of the driver? This could be an improvement in the amps too since I used a smaller coupling capacitor between the driver tube and the output tube of my SE amps, which means that the output tube is not trying to reproduce deep bass.
Retsel
The thing I've always liked about speaker design and acoustics is that it's very complicated. Perfection isn't quite possible, and yet in spite of all the challenges, our efforts often leave us with a very enjoyable result. It's intriguing to say the least. I find it really doesn't need to be perfect to be great. Understanding acoustics and how the ear-brain mechanism works may be the biggest challenge. I've gotten to the point of me feeling limited by the recording process, to the point where I'm considering creating my own recording setup.
One of the challenges with the reproduction process is how to lessen the damage of inter-aural crosstalk during playback .The Carver and Polk methods of dealing with that show me how much sense of reality we've lost there.
There's a local Bluegrass band I'd like to record. I'm thinking PZM's wide spread for below 1kHZ, and a stereo head mic for above 1kHZ, w. active crossover and EQ on each, and I'm not sure a high order crossover is even desirable for such an arrangement. I have a suspicion that this arrangement might work pretty good. If I had the time and money...
But I'm getting off subject here.
One of the challenges with the reproduction process is how to lessen the damage of inter-aural crosstalk during playback .The Carver and Polk methods of dealing with that show me how much sense of reality we've lost there.
There's a local Bluegrass band I'd like to record. I'm thinking PZM's wide spread for below 1kHZ, and a stereo head mic for above 1kHZ, w. active crossover and EQ on each, and I'm not sure a high order crossover is even desirable for such an arrangement. I have a suspicion that this arrangement might work pretty good. If I had the time and money...
But I'm getting off subject here.
Last edited:
I'm not Earl but I observed same thing. However, Lowther has a 2mm? X-max, relieve them from bass and distortion goes down. Asking a wide band unit to do serious bass and treble is asking for trouble. I think the distortion Earl talks about is within a "decent" level and within the drivers capabilities...
Hi Retsel
I cannot comment on your experiments I wasn't there.
A few things about "Doppler" distortion. It is indistinguishable from normal IM distortion except for one thing, the sidebands for Doppler are out of phase while for IM they are in phase. What happens in a loudspeaker is that if the two things are at about the same levels then the two sidebands to an upper tone are not the same height, one is taller than the other. But if the two sidebands are about the same height then you cannot tell if they are due to Doppler or due to IM. That makes measurements pretty hard to interpret.
But yes I would say that Doppler is not an audible artifact. It is low order and as such is masked. Virtually all nonlinearities in a loudspeaker are low order and it has been shown time and time again that low order nonlinearities are not audible. There can be high order nonlinearities in loudspeakers, but then we would usually describe these loudspeakers as broken.
What I am saying is that these low level effects, like Doppler, are not audible in a loudspeaker because the are always masked by our hearing mechanism, which is itself nonlinear. Only high order nonlinearities and particularly ones that do not shrink as the signal falls, such as crossover distortion (which can happen in a badly made loudspeaker) are audible. This is what everyone who has studied this problem has concluded.
"Logic" does not come into play when we are talking about "perception" where complex cognitive processes like hearing are involved. "Logic" simply goes out the window in such cases and you have to be very careful with how you do tests.
Last edited:
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.