Whether amps increase damping or decrease it... This is chicken or egg type stuff. The question is compared to what? Compared to shorting the speaker leads, yes it will always reduce damping. Compared to having the speaker disconnected, it will always increase damping.
So which scenario is more applicable to how we use speakers normally, leads shorted or leads disconnected? Personally I haven't had much luck unless they are connected to an amp. Wait, what is the output impedance of that amp? Uh oh. It's a superposition, a quantum entanglement!
So which scenario is more applicable to how we use speakers normally, leads shorted or leads disconnected? Personally I haven't had much luck unless they are connected to an amp. Wait, what is the output impedance of that amp? Uh oh. It's a superposition, a quantum entanglement!
Well, that shuts down the conversation right there!
I will gladly respond, but not when you have that tone. I don't respond well to condescension and ridicule, so a change of tone please and you and I can have a good and constructive discussion. But clearly you want a combative one and have a need, I don't.
It seems like that is somewhat infered by KSTR, given that the driver isn't damped by the amplifier like seen in the cone tap test.
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Now here is the kind of professor that I admire. I took his courses, along with Robert G Meyer, at UC Berkeley between 1971-1973 when I could get off work. Dr. Donald O. Pederson was a true engineer, with both practical and theoretical experience. Here is where I 'finished' my engineering education. He is long deceased now, but the IEEE made a medal just with his name, to give deserving engineers. Here is one: Larry Nagel
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Joe, why don't you actually measure the distortion of your Elsinore speakers and present the results here? It's not that hard. It gets confusing sometimes you discuss voltage vs current drive and the distortion of the transducer and then sometimes you refer to your "physics friend" and the class A/B amplifier distortion (which IMO is of historical interest only).
T, I wish to tell you something very important. As you know I have been professionally designing audio circuits for over 50 years now. I am a pretty darn good circuit designer, one of the best, but there is more to audio success in my experience than a pretty circuit that measures well. Usually I depend on others to clue me in in these other areas, which might include caps, solder, ckt board material, and even connecting wire. I go with what works! Not what is impressive to talk about, or most expensive, or whatever else. Would you depend on wine quality by pure measurement? I doubt it, and it is the same with me with passive devices. Even if I personally can't measure any difference, I have depended over the decades for serious audio listeners to give me tips on what to use. THEN I listen for a difference if necessary.
IF you could trust Dr. Vandenhul or someone equivalent, you could learn new stuff too. Perhaps Yves Benard Andre? He could clue you in. We met in Paris once and he and his wife were really nice to us. He also beat my Vendetta Research in a direct comparison once. His company was YBA. You should look him up.
IF you could trust Dr. Vandenhul or someone equivalent, you could learn new stuff too. Perhaps Yves Benard Andre? He could clue you in. We met in Paris once and he and his wife were really nice to us. He also beat my Vendetta Research in a direct comparison once. His company was YBA. You should look him up.
We are speaking about damping in RLC circuits and everyone with at least basic knowledge knows that damping of the RLC circuit step response depends on ratio between R and sqrt(L/C). Amplifier Rout may contribute to R slightly, but even Rout = 0 cannot make any "damping" if the condition for R/sqrt(L/C) is not fulfilled. Audiophile theories are mostly stupid, and discussions as well.
RLC circuit - Wikipedia
Measurements can show much more differences than any ear is able to tell, provided we have omitted psychoacoustics. However, measurement results may be uncomfortable to someone and not in accordance with what is stated purely verbally, without any proof. That's why I became very skeptical to most of discussions here, that are not supported by raw data.
I hope you finally get it, there are certain things simply beyond capability of regular people like us to do anything.
Assuming your premise is correct, provided that it does not violate any of your NDA or trade secret, can you please share with us measurements that you have related to spatial or localization cues?
ScottJoplin showed me the pinnae transform technique to generate localization cues on another thread, but both of us still has vague understanding about how to optimally reproduce the spatial cues on regular recordings.
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We are able to measure with unexpectedly good resolution event at speaker acoustical side. There were some remarks on class AB amplifiers and I have to concur that class AB crossover distortion is often measurable at acoustical side. As a reference, I use a pure class A amplifier, with distortion components only H2 and H3 and below 0.001%, with all other higher harmonics well below -130dBr. This is still not usual even with well designed class AB amplifiers, especially if we are in the crossover area. Acoustical measurements at quite low voltage level, however quite usual during normal listening, show, that higher order harmonics at the acoustical side are really extremely low in level and that a crossover "signature" of class AB amplifiers is very often higher. Not speaking about tube amplifiers, which would be in orders higher. Class A with local linearization is still the best we can design, especially its immunity to load variations. Class AB amps still do have its signature.
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I am about to surprise you...
What you ask is not unreasonable and while John just said that he would not rely on measurement for everything, and I largely understand his reasons. but in this instance I am working on something that I believe is measurable.
So in time I will indeed produce a very precise set of measurements. It should be able to verify distortion on both the electrical side and the acoustic side. This will not be labelled as fairy floss. Dan (Max Head) has spoken to me on the phone and has some idea of what I have in mind.
Pavel, PMA to us here, has done a series of measurements comparing voltage and current drive. His intent was to compare the two drives. He adds certain comments, all very fine, but he does not explain the mechanism, he only refers to the end result. But would knowing be more important? Why is the distortion lower is more than just observing the distortion being lower.
And knowing has nothing to do with as to whether voltage or current drive, not interested in that fight. I have been constantly associated with the current drive camp, when in fact I am in the voltage drive camp. I just want the lower distortion. I keep telling people that current drive is never going to take over the world. No retailer is ever going to sell something that can blow up other speakers he has in his inventory.
But what I do say is this, there is something about current drive that tells us what we should do to get voltage drive right and get lower, and hopefully measurably lower distortion. So John Curl can go on designing his voltage power amps along with preamps.
But these measurements will have to be highly developed, and documented and repeatable by others. Yes, peer review-able and peer repeatable. That should satisfy even you. Anybody!
You might be surprised at what I am capable of, I have done my fair share of R&D over the decades. I have a confession, my Avatar on the left was taken 20 years ago with an early Kodak digital camera. I am beyond retirement age, except I have not retired and my health is holding up - and I still have things to do.
So yes, some serious measurements are in the works, but Pavel's are good, but there is something he is yet to do.
Hope Pavel doesn't mind, the tweeter voltage driven:
The same tweeter current driven:
Kudos to Pavel. I have done the same and more... with is more to come. And it will be about what one can do to voltage drive and hopefully get the distortion of current drive. That should be of interest to all of us here.
PS: I admit that my language is at times unconventional. I am aware that irks some and yet gets praised by others. I have gone toe-to-toe with many scientists and engineers and my style, and it is a style that I have fostered, actually helps them to think in different ways and have been praised, not ostracised. So I will keep doing it.
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Not sure why, it worked when I posted them. Maybe PMA blocked them, that is his right if he did. I linked them from his website.
They show that you get lower distortion products under current drive when compared to voltage drive. What I propose is that there may be measurable improvement with voltage drive too. Lower distortion with voltage drive, that ought to be good.
Hans van Maanen of Temporal Coherence has commented on this as well. Consider this, the transition from Class A to Class B, the voltage and current not lining up (current phase angle) and the feedback of the amplifier can only correct for voltage will produce higher order distortion products. So yes, using Class A is a good thing for these kind of measurements.
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