John Curl's Blowtorch preamplifier part II

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I hear and can measure small diffences in cables but i whould not sign that cables have to be expensive. What i really know is, that termination makes a difference so i try to solder well and use good contacts.
What i really do not like are exotic cables that really change the sound much but they have usually extremely high values of capacitance so it is no wounder that they sound "fuller", "more spacious" or "warmer".
 
Sensible, 2 Quad. I have never, in recent years, been a true believer in ultra low distortion for its own sake. I seriously don't believe that .01% 3rd harmonic distortion is audible in a worst case situation. It is just too small of an amount, compared to loudspeaker, analog magnetic tape, and perhaps other distortion sources.

i respectfully disagree.
.01% 3rd harmonic distortion may not be masked by other 3rd due to the phase differences.
also, micro-resonances in the loudspeaker may boost the level of the distortion by 20 dB or more relative to the fundamental.
 
Think analog magnetic recording and the wonderful musical sources recorded in this medium. If .01 percent distortion, especially on musical peaks, could be detected, ALL analog magnetic recording would be in the scrap heap. 30ips down to cassette. If you doubt me, give me some evidence that it could be detectable. Remember, at listening levels the JC-1 is about 130 dB down or .00003 percent.
 
I am glad that you also see the light, Joachim. Distortion by absolute number, is NOT everything in an electronic device. I wish that it were, as then it would be an easy target.
Many engineers working in other fields think that this should be so, but experience with REAL listening of the BEST audio components available throughout the world, show that distortion is but one component in quality playback. Some distortions (like FM) may remain hidden, yet others, like simple harmonic distortion, might be embarrassing to some, yet the sound quality is wonderful. Why this is so, has been my quest, and others as well, for the last 40 years.
 
Do you know that originally, back in the 1950's with Scotch 111 mastering tape, 0 Vu was 1% 3'rd harmonic?
When I worked at Ampex, in 1968, the 3'rd harmonic distortion level at 0 Vu had dropped to about 0.7%...
Turntables typically produce a similar amount of 2'nd harmonic due to arm/cartridge geometry. It does not surprise me that this is not audibly bad, however I wonder about the fact that nobody seems to notice the variations in distortion (between zero and perhaps 0.5%) as the cartridge moves from the outermost groove to the innermost.

We don't find, for example: "Track 3 starts out very clear and detailed - perhaps a bit analytical, but rapidly acquires a more tube-like warmth as the distortion rises".
 
Vinyl distorts horribly and it is audible everywhere, of course especially near the end of the groove. Happy those who are unable to hear it.

In the days before magnetic tape recorders transcription discs were used. On a long session this required more than one disc. So the first one in a set was recorded from the outside in the same as today, BUT the second one was recorded from the inside to the outside! That way there would not be an abrupt change in sound quality when the discs changed over. The third would be outside in and so forth.

So what was a problem in 1930 can still be one today. But good news for us as today digital recording is perfekt!
 
Vinyl distorts horribly and it is audible everywhere, of course especially near the end of the groove. Happy those who are unable to hear it.

Wow, that's an interesting remark.
I'm curious as to what phono electronics you are using. Don't care much about what expensive TT/arm cartridge combo. The signal from the cartridge is incredibly fragile to get through intact.
 
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