John Curl's Blowtorch preamplifier part III

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I agree the PSRR is over stressed in audio with modern IC devices. There are plenty of good regs out there and the humble 7815 is not bad. As you say Richard, add a cap multiplier if you are worried about it.

Sure, the 7815 is not bad, but it's not very good either. Good regulators have lower output impedance over a much wider frequency range. I believe that even with circuits with good PSRR a superior regulator makes an audible difference. Of course, I have absolutely no evidence to back that up. :)
 
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Just some other cap coupled stages of yesterday...I wondered what geniuses must have been the Tandberg guys to keep all their sh..t together in that schematic and give a masterpiece of tape recording with no fet transistor and no global feedback , but look at their headphones amp section!
That is the next amp i'm going to build!

It fully got my attention.
 

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Dreamth - you should read all of Bateman’s papers on electrolytic capacitors before you go further.

Hers a link to one of them, it clearly shows the lowest distortion in electrolytics is for a bipolar electrolytic ( and even better is a series pair of bioplars.)

https://linearaudio.nl/sites/linear...0 to 100uF caps and 100 Hz measurements_0.pdf

And good luck finding the Japanese transistors in your project schematics
 
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Yes, I've noticed him saying this too. So @JC - does it seem to you that you 'fight the idea of un-sighted listening with a passion' ? Or do you simply avoid it - in the way I avoid Brussels Sprouts - because it doesn't suit your purpose?

That was sweet of you to put words in his mouth. What do you take his purpose to be which is so unsuited to ears-only evaluatin?
 
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Sure, the 7815 is not bad, but it's not very good either. Good regulators have lower output impedance over a much wider frequency range. I believe that even with circuits with good PSRR a superior regulator makes an audible difference. Of course, I have absolutely no evidence to back that up. :)
The best regulator is no regulator...but let's just see what Audio note did with the 7805 maybe we get something out of it:
 

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Dreamth - you should read all of Bateman’s papers on electrolytic capacitors before you go further.

Hers a link to one of them

https://linearaudio.nl/sites/linearaudio.net/files/Bateman%20EW%2001%202003%20mar2003%2010%20to%20100uF%20caps%20and%20100%20Hz%20measurements_0.pdf

And good luck finding the Japanese transistors in your project schematics
I have read it all 3 years ago as part of the job spec i had! I was payed to read Cyril's articles if you can believe it!
Better read here:
Nichicon Muse ES bipolar caps measured: <-120dB THD, <-140dB IMD
And i have all the transistors i might ever need.I have literally a ton of vintage equipment in my little apartment...No insect dares to enter my home because of the smell :)
 
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Good use of CRC on the input side. The utility of the output side though escapes me....
I took myself the time to build a loaded capacitance multiplier this way and i was please with the results, but indeed , 78lxx series is very good .I use them extensively everywhere and load it accordingly...Most people load it minimally but they need more than 5...10ma load to work best and besides that i always put enough low esr capacitance at the output.
 
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If you could enlighten me on how seeing or not helps sort that out it would be appreciated.

It was merely my speculation you're engaging with. I admit my speculation could well be in error. Seems too academic to me to continue with this line of discussion until @JC responds to falsify (or other) the speculation.

The thinking behind my speculation was that I've only ever heard of blind testing to be done in conjunction with trying to hear differences. When I asked a proponent of blind testing (on this forum) how to use it in order to listen for improvements he informed me that I would need to confirm that there was indeed a difference first but gave me no reasoning. I didn't find that assertion at all convincing myself, if you have reasoning then I'm all ears.
 
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There was a psychological study in the 50's in the USA, where two groups of people were asked to put their palms over a small hole made in a box and tell if they feel anything at any time.One group was told that in the box is a light and someone is acting a switch randomly so that group was notified that they need to feel when the light was on.The other group was not told anything.
After many trials , the statistics was like this: The group who knew about the light was able with some "training " to get the time when the switch was on in about 70% of the cases while the group who wasn't told the secret was never able to tell when the switch was on.
The conclusion was that our senses are also educated by our expectations and in the end the cells in out skin have the basic ability as any other living cell to perceive light as form of energy but it's only the eye who is specialized and wired to the brain in a more efficient way.
Even the ABX box can be cheated with proper training.
YouTube
https://youtu.be/ppe4O1H4tIw?t=444
 
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