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Old 13th July 2012, 11:59 PM   #24441
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Quote:
Originally Posted by john curl View Post
Yet, critics of mine, like Scott Wurcer has apparently never heard of the company. Go figure! '-)

Yes, I admit I pay little or no attention to things like MIT or Cardas wire or Geoff Kait's brilliant pebbles, myrtle blocks, the list goes on and on. Embracing all of them uncritically does not flatter your abilities. You don't need them, you are better than that.

I am only a critic of inaccurate or just plain mis-information or out and out fraud. I even admit I pay so little attention to the outsider audio industry that Dick's involvement with Rel Cap escaped me, which is probably a good thing.
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Old 14th July 2012, 12:16 AM   #24442
jcx is offline jcx  United States
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without signal theory, physical device equations, models, numbers, correlated with controlled listening results, any psychoacousitic data I really can't see the cause for your smugness

"I often say that when you can measure what you are speaking
about, and express it in numbers, you know something about
it; but when you cannot express it in numbers, your knowledge
is of a meagre and unsatisfactory kind ...
--- Lord Kelvin

Last edited by jcx; 14th July 2012 at 12:22 AM.
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Old 14th July 2012, 12:22 AM   #24443
RNMarsh is offline RNMarsh  United States
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Originally Posted by DF96 View Post
According to the graph it is peaked! Maybe 1-2dB? The Q is a bit too high.
That is completely beside the point -- (that line up 1db is an artifact of the crude software graphing being used on this old MLSSA). The point should be clear that I am talking about the sum total energy at the crossover area. And, as I said the description of the sound in that area where the decay is slow is similar to masking and distortion .....it would sound peaked anyway. If you add up each curve, the total power curve is VERY peaked.
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Old 14th July 2012, 12:36 AM   #24444
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Originally Posted by RNMarsh View Post
Geeez did you guys miss the point? I am talking about test equipment measurements which correlate better than freq response or thd. It seems to have gone right over the heads of the readers here.
We are often told -- that because the thd or phase or freq response is super good, listeners are nuts to hear what they say they hear. It started with caps but I moved on to other areas.... you guys are still on caps and distortion? You are making yourselves look bad. -RNM
We talked this topic to death in Lounge.

There is a dedicated topic, about sound quality and measurements. Your point is, group delays is what matters. My point is, much more. A first, nobody proved that we recognize sounds by harmonic content, so we may assume that waveform matters. It includes your postulate as well, about group delay. But a waveform is more than a group delay.
You are banging in already wide opened gates. Come in!
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Old 14th July 2012, 12:36 AM   #24445
morinix is offline morinix  United States
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I wish I could afford all these hotsy totsy caps but on my budget I just have to happy with Wima foils.
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Old 14th July 2012, 12:37 AM   #24446
RNMarsh is offline RNMarsh  United States
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Default Low distortion cap sounds compressed on music --

Another view of how things sound and a test measurement that correlates: The peak current thru two caps of same voltage applied and same value. One film and foil and one the popular bipolar cap --- listening says the bipolar makes the sound compressed in comparison. This is yet another view of cap behaviorPeak current compared.jpg - especially useful info if making speaker crossovers. -RNM
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Old 14th July 2012, 12:41 AM   #24447
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Originally Posted by morinix View Post
I wish I could afford all these hotsy totsy caps but on my budget I just have to happy with Wima foils.

And a controlled listening "shoot out" will never happen, ever.
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Old 14th July 2012, 12:44 AM   #24448
RNMarsh is offline RNMarsh  United States
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Quote:
Originally Posted by Wavebourn View Post
We talked this topic to death in Lounge.

There is a dedicated topic, about sound quality and measurements. Your point is, group delays is what matters. My point is, much more. A first, nobody proved that we recognize sounds by harmonic content, so we may assume that waveform matters. It includes your postulate as well, about group delay. But a waveform is more than a group delay.
You are banging in already wide opened gates. Come in!
Thank you. It is NOT my point that group delay matters. My point is simply that when listeners say they hear something and describe it, consistantly .... there are measurements that seem to correlate to that very audible description.

Last edited by RNMarsh; 14th July 2012 at 12:47 AM.
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Old 14th July 2012, 12:46 AM   #24449
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Originally Posted by RNMarsh View Post
Another view of how things sound and a test measurement that correlates: The peak current thru two caps of same voltage applied and same value. One film and foil and one the popular bipolar cap --- listening says the bipolar makes the sound compressed in comparison. This is yet another view of cap behaviorAttachment 291482 - especially useful info if making speaker crossovers. -RNM

Time smear on a 1us time scale, you have to do better than that. Please submit these results to an unbiased listening test, no measure and send to audio buddies. I have seen no controlled by any standards test to support these conclusions.
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Old 14th July 2012, 12:58 AM   #24450
RNMarsh is offline RNMarsh  United States
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Originally Posted by scott wurcer View Post
Time smear on a 1us time scale, you have to do better than that. Please submit these results to an unbiased listening test, no measure and send to audio buddies. I have seen no controlled by any standards test to support these conclusions.
Sooooo literal --->
This was discussed in more detail at DSPx in 1995. You dont have to believe it or even do a listening test - already done years ago. Its the effect of esr of the bipolar & film that is being shown. The effect is greater with larger cap values, of course......and heating due to repeated high currents transients only makes the esr worse. With bipolar caps the dielectric is significant part of the esr as well. I am sure you can extrapolate the time scale yourself with a typical (100+ mfd) cap used in speaker crossovers. Larger values (than this example using 1mfd) like those used in speaker crossovers would be subject to possible esr modulation as well...and thus phase modulation of the filter slope....though I didnt measure or hear from others a sound description that indicates it is audible or significant that way. Live and learn. I put it here for all now and in the future to do their own eval. its another test current impulse test (non sine wave) besides THD on caps. -RNM

Last edited by RNMarsh; 14th July 2012 at 01:26 AM. Reason: more correlations -
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