When sales decline far enough, certainly when there is a long period with no new designs you issue a last time buy notice. We have BTW sold designs to outside companies that have small but steady sales, there is still one running from 1968.
No we just enable someone else make it and sell it. It's pretty rare. In the case of say the AD844 who would bother, it really is about no more complicated than the simplified schematic and no one has an exclusive right to that topolgy.
The purpose was to have an economic shieded cable, on one side, and it was question of 3 cat 6 for 8 ohms.(each one composed of 100/4 = 25 ohms).
One thing witch has not been mentioned is, if the lengths of the paralleled cables are a little different, reflexions can be a little more randomized.
Cut them to the same length. If you twist them to different pitches, they'll act like a cat5/6 cable..totally independent fieldwise. If you don't twist them, keeping them apart half an inch or so would be enough to prevent coupling.
A really good braid might actually be worse than random bunching if you keep the conductors flat.
Yup. It doesn't have to be to four digits, I'd just try to keep the cable z within an order of magnitude of the lowest..splitting the diff is probably good enough.
It might even pay to get as close to 1Khz speaker z as possible..I think that's where we work the best.
Don't forget...this delay stuff may or may not make a darn bit of audible difference. The actual existence of delays due to line load mismatch doesn't prove audibility.
jn
Yes, audibility is in question, but if the physics are good and the implementation is not hard or expensive, why not? I have some Mogami cable I've never used because of the high capacitance issue. At the time I bought it years ago, I thought it would help shield against RF entrance to the amp via the speaker wire. Now trying to re-evaluate its use. I presume an RF termination a la the Pass article would help.
Small changes won't make much difference to reflections. If the resistance is significantly different, current imbalance would trash the lowering of inductance.
jn
You are right, my mystake. I forget the speed of the light, so used to deal with the sound's one
Try 5534/32
CABLES etc
Just a gentle reminder that Absolute Listening Tests-Further Progress describes an easy way to test AND LISTEN to the effects of cables. Our results confirm Nelson's.
Pass reinforces my experience that practically all Golden Pinnae amps have wonky sensitivity to load. I first encountered this in a Levinson amp circa 1979/80
Christophe, as a speaker man, I've been guilty of deliberately designing speakers to present evil loads to wonky amps. If I ever abandon the beach, I'll have to adopt Nelson's or your methods so Golden Pinnae amps won't be embarrassed.
Of course, the real answer is for the wonky amp designers to actually do proper tests to ensure unconditional stability with load ... instead of just insisting ad nauseam that their designs can't possibly be wonky.
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In a way, it is logical: As i wanted the max available open loop bandwidth in my amp, (Golden ?) i have few stability margin and huge bandwidth. If my amp was signed by a mass product label, and sell by million of units, i would not take any stability risk about, with any charge. A Ferrari is often in garages.
What i don't understand is why resellers of zillion dollars audio for the few, with BIG margins, do not take care to verify with an oscilloscope that the Golden system they are about to sell does not overshoot with square waves. They have golden ears too, no need ?
Richard, my method include what you call the Nelson's one.
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I would like to KNOW exactly what both of you insist upon to insure that an amp is stable. A coil will not necessarily do it, so don't insist on that. Just WHAT should designers do, that you suspect that we don't do, to test for stability?
Now, when it comes to Mark Levinson in the late 70's-80's, you have to blame Tom Colangelo, then in charge for 3 years or more for the amp designs. Unfortunately he is deceased and can't answer for himself.
Now, when it comes to Mark Levinson in the late 70's-80's, you have to blame Tom Colangelo, then in charge for 3 years or more for the amp designs. Unfortunately he is deceased and can't answer for himself.
" I've been guilty of deliberately designing speakers to present evil loads to wonky amps. If I ever abandon the beach, I'll have to adopt Nelson's or your methods so Golden Pinnae amps won't be embarrassed." KgrLee
Do you think that it was necessarily the loudspeaker or do you think that perhaps the unusual load was in the xo before the device? I have been guilty of doing that with a network that created a nice resonant system when driven, not a nice result with an amplifier running in bridged mode. Nice puffs of smoke and damaged output devices....... Lesson learned.
Do you think that it was necessarily the loudspeaker or do you think that perhaps the unusual load was in the xo before the device? I have been guilty of doing that with a network that created a nice resonant system when driven, not a nice result with an amplifier running in bridged mode. Nice puffs of smoke and damaged output devices....... Lesson learned.
It is an organized gang. (Are-you part of them, i was not commenting about your designs ?)
Amps designed to feed pure resistances, Capacitives huge cables, non zobeled enclosures, or worse like Quads. Read Nelson's problems reports, is-it serious ?
Coil or not coil, chose your poison, everybody is free to buy a Ferrari. It is expensive, it is fragile, it drink gaz, it is noisy, it run too fast for countries with speed limitations. Are-we allowed to feel such cars not 100% accurate and prefer Hondas?
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Thanks for joining in JC. If I list my tests, will you list yours?
Or are you going to insist that your designs can't possibly be unstable into real speaker loads so no testing is necessary ? I hope you won't take this attitude ... as you've taken with the Hirata & Quan tests?
JC, I see ML2 is your work. Can you tell us what Tom did to your design to make it only marginally stable. When did these evil changes take place? Did you discuss this with him?
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The xover is certainly a big factor in such evil.
The Pass paper and some of these discussions on Golden Pinnae amps suggest I should do more to allow for wonky amps.
As a humble speaker man, I used to assume amps will be happy as long as I kept above a minimum Z. My small experience shows this takes into account the times when speaker Z is seriously non-linear too. But some Golden Pinnae amps are obviously much fussier.
The obvious take from all this is that one shouldn't be surprised that some Golden Pinnae amps sound very different compared to boring stuff that's unconditionally stable with load ... esp with tweaky cables. As Scott says, Nelson's paper makes this very clear. As does "Absolute Listening Tests ... "
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