Audiophiler capacitors on ebay

[gil1]

Anyone used these caps? Opinions?

http://shop.ebay.com/?_from=R40&_trk...All-Categories

[gil1]

Well, I will answer my own question...if something sounds too good to be true, it is! Went ahead and purchased some of these caps (not a lot of money) to use on the signal path of a couple of my preamps and right away the difference was noticeable, the highs and the mids became attenuated, almost like if a blanket was covering my speakers. Break in time? Well, a week after using them still sounds the same, somewhat dull. I would not recommend these caps.

[benchtester]

Thanks for the advice.

[tubesteve]

were can i calibrate my ears for hearing these differences of the cap?

[audi0]

Originally Posted by gil1

Well, I will answer my own question...if something sounds too good to be true, it is! Went ahead and purchased some of these caps (not a lot of money) to use on the signal path of a couple of my preamps and right away the difference was noticeable, the highs and the mids became attenuated, almost like if a blanket was covering my speakers. Break in time? Well, a week after using them still sounds the same, somewhat dull. I would not recommend these caps.

Question: did you give them a chance to 'burn in'? Maybe you were a bit haste with your judgement?

[tubesteve]

some people may have noticed, that human senses are not reliable and stable in performance. therefore we engineers like to test with equipment. a small infection which even may not be noticed can easily affect the hearing. the dull effect some are noticing may more be due to the output filter snubber caps as the frequency response in the higher treble range falls down caused by them. this intended to protect speakers against RF power, and also for EMI reasons. but if there may have any doubt, buy new caps, put them into the amp, and sweep a signal with a known voltage thru the amp with a known output voltage, connect an oscilloskope and record the response. repeat the same after a time when you thinks the sound is dull. dont use speakers as a load, use fixed 4 or 8 ohm power resistors, then compare both records. differences of 3 dB ( = half power) can barely be noticed by most people. if the scope has an FFT mode, you can see results directly in dB

[analog_sa]

Originally Posted by tubesteve

but if there may have any doubt, buy new caps, put them into the amp, and sweep a signal with a known voltage thru the amp with a known output voltage, connect an oscilloskope and record the response. repeat the same after a time when you thinks the sound is dull.

This test will obviously reveal nothing at all. I guess you are more inclined to believe we all have ear infections

[wintermute]

Originally Posted by tubesteve

were can i calibrate my ears for hearing these differences of the cap?

Hi TubeSteve, I'd advise having a read of walt jungs Picking Capacitors article. Walt Jung is an engineer, and a very well respected one at that. His article takes an engineering approach to measuring the differences in different capacitors, and then relates what is measured to the subjective statements that people make about how capacitors sound different.

The stuff on dielectric Absorbtion, and the compression effect that it has as well as the contribution it has to adding "noise" to the signal reducing the accuracy is very enlightening.

Part 1 and Part 2 of the article for your convenience

and a quote to wet your appetite...

Dielectric absorption becomes a critical factor in circuits which are highly dependent upon speed of response. As the a.c. signal goes to zero (as in a short circuit) the trapped or bound electrons within the dielectric do not follow as fast. These electrons take a finite time to move from the dielectric to the electrode. As capacitors are typically used in audio circuitry, we could translate these defects into loss of accuracy in reproducing the fine inner detail of music, as well as the music's dynamic structure.
It is quite illuminating to consider what effect a phenomenon such as DA will have on an a.c. signal consisting largely of transients (such as audio) might have. For example, when an a.c. voltage is applied, there is a tendency for the dielectric absorption phenomenon to oppose this change in polarity.
When music is the a.c. signal, the sonic degradation is one of compression or a restriction of the dynamic range. Also, a loss of detail results, and the sharpness is noticeably dulled. With dielectric types which have high DA, there is a definite "grundge" or hashy distortion added to the signal.
It is quite important to describe the sonic thumbprint that DA contributes to subjective audio. The effects of DF and DA can be perceived differently. DF is primarily a contributor to phase and amplitude modulation DA reduces or compresses dynamic range. This it does by not returning the energy applied all at once. With signal applied to a capacitor with DA present, the amplitude is reduced by the percent DA. When this energy does get returned (later), it is unrelated to the music and sounds like noise or "garbage" being added; the noise floor is also raised. High-frequency and/or transient signals are audibly compressed the most. Signals that look like tail pulses (a lot of transient music information is of this nature) are blunted or blurred in their sound. "Dulling," 8'loss of dynamics," "added garbage or hash," and "an inability to hear further into the music" have been subjective terms used to describe the DA effect in capacitors.

Tony.

[audi0]

Originally Posted by analog_sa

This test will obviously reveal nothing at all. I guess you are more inclined to believe we all have ear infections

+1

[tubesteve]

i think slowly, the placebo effect also now works in audio, not only in medicine. next i will employ some hifi fans into my lab, to judge the results. i will no more perform any testing. it seems, people are better and more reliable than any test equipment. since 37 years i did audio design and testing, so i was completely wrong...............