John Curl's Blowtorch preamplifier part II

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Welcome to being human. :)
The very first time I tried Signetics NE5532s, I was VERY biased in favor of it. ICs were hype, very much used in my profession, and this one had everything that i was dreaming-of in its data sheet. I was so badly surprised by the way its sounded, that i had to verify nothing was wrong, rails side, by changing decoupling caps, impedance of the feedback, no oscillation etc...
I asked several colleagues to confirm or infirm my feeling in AB tests (I hate ABX). Same opinion.
It was at this time I made a board with 4 ICs (inverting/non inverting, unity gain/gainX10) and various loads to be compared instant with a wire.
Now, you can tell-me what you want about it, you will never see one of them in one of my devices at home.
And, now, if you ask-me why they sound so boring, I'm totally unable to explain by any measurement numbers or any theory. And certainly not because it is ICs. (I LOVE my OP260s)
 
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diyAudio Member RIP
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I have one of those on my desk, plugged into an octal Amphenol socket adaptor to keep it upright.
Heathkit also made some knockoffs for their analog computer.
Yes the UCLA Astronomy Dept. had one of those Heath analog computers. My physicist friend saw that it was gathering dust, and got permission to move it to the electronic music studio, where I also worked for a while. He restored it to service (I remember the Sola constant-voltage ferroresonant transformer) and set up some differential equation patches. The machine was also a shock hazard, with the nominal voltage range of the signals +/- 100V.

Of course none wanted to play with it save he. These guys were having a hard-enough time using the big Moog and their patches with 1/4" phone plug cables, or the Buchla, with 3.5mm ones. One composer I had to help, and he was not the sharpest razor blade for the tape splicer, would have me explain how a patch worked, and step-by-step make the connections. Then he insisted that everything be unplugged so he could try to replicate it. Some very long days.
 
so badly surprised

Preamp of the late '80s.
As you can see, in the line stage, each 5534 drives a class A biased PP output stage. (mind the stripe, Signetics)

I applaude your ears, if you'd find it all that 'bad' sounding.

(by no means implying this is the best I've ever listened to/through)
 

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The very first time I tried Signetics NE5532s, I was VERY biased in favor of it. ICs were hype, very much used in my profession, and this one had everything that i was dreaming-of in its data sheet. I was so badly surprised by the way its sounded, that i had to verify nothing was wrong, rails side, by changing decoupling caps, impedance of the feedback, no oscillation etc...
I asked several colleagues to confirm or infirm my feeling in AB tests (I hate ABX). Same opinion.
It was at this time I made a board with 4 ICs (inverting/non inverting, unity gain/gainX10) and various loads to be compared instant with a wire.
Now, you can tell-me what you want about it, you will never see one of them in one of my devices at home.
And, now, if you ask-me why they sound so boring, I'm totally unable to explain by any measurement numbers or any theory. And certainly not because it is ICs. (I LOVE my OP260s)

Christophe,

I don't doubt your experience at all, nor would I suggest that you consciously have any biases. And for all I know the NE5532 was being used/loaded oddly such that it was acting wonky.

Likewise, I really hope you're happy with the listening experience you have.

That said, I'm going to continue to struggle with these subjective assertions of how an IC sounds, especially when it's a series of personal anecdotes.
 
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