You might be more right than you realize, hitsware. Thermal feedback, especially with Class B output stages is a real potential problem.
There are some real differences between IC's and discrete. One is the lack of complementary jfets in IC's. I can't design my best with them.
I just got a full demo card of our AD1955 DAC our ESS 9018 "equivalent". In their infinite wisdom it was laid out to facilitate op-amp rolling.
In my experiments with AD1955 a few years back I found the LM6172 to sound the best and with the lowest possible feedback capacitance that still sounds OK. I think I ended up with 4.7pF. Trying NE5532 there, with no feedback capacitance is an interesting experience, to say the least 🙂
Philbrick k2-w it had 2 12ax7 tubes with an octal base 1952. Have one in grey .
> Thermal feedback, especially with Class B output stages is a real potential problem.
That's the least problem. On the scale of IC construction,
audio acts like RF to a great extent. Everything bleeds into
every thing else. Most IC's in and out of a circuit give the
effect of a blanket between (and then not) the speakers and ears.
That's the least problem. On the scale of IC construction,
audio acts like RF to a great extent. Everything bleeds into
every thing else. Most IC's in and out of a circuit give the
effect of a blanket between (and then not) the speakers and ears.
it was a real question. I have not the slightest idea of how ICs are made.
Thanks for the answer.
(sofaspud, I use no translator, only to understand jacco's French ;-)
So is a blanket worse than the 'veils' that most audio writers love to talk about? And surely so much HF attenuation would be clearly measurable?
> So is a blanket worse than the 'veils' that most audio writers love to talk about?
Same.
> And surely so much HF attenuation would be clearly measurable?
More mixing than attenuating. I think all here agree that ears can
discern beyond instrumentation.
Same.
> And surely so much HF attenuation would be clearly measurable?
More mixing than attenuating. I think all here agree that ears can
discern beyond instrumentation.
I think that is more contentious than op-amps vs discrete! Actually the ears are OK, its the brain that they are connected to where the problem starts😛
It is hard for me to grasp. If it can be such an issue at audio frequencies, how does it jive with actual RF ICs?
Its only perceived as HF attenuation, but in reality its the addition of HF noise correlated with the signal. So the FR will still measure perfectly flat.
Sy,
How about that the interpretation of what is measured is misconstrued? The measurements can be totally accurate but the context of the use of those results can be misapplied. Is that a better way of looking at this than saying that the measurements are not accurate when we know they are? There are no ways to calibrate anyone's hearing as far as I understand it so that you can make comparative analysis from hearing alone between parties. The agreements are only contextual, not scientifically accurate in any real sense.
How about that the interpretation of what is measured is misconstrued? The measurements can be totally accurate but the context of the use of those results can be misapplied. Is that a better way of looking at this than saying that the measurements are not accurate when we know they are? There are no ways to calibrate anyone's hearing as far as I understand it so that you can make comparative analysis from hearing alone between parties. The agreements are only contextual, not scientifically accurate in any real sense.
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