Oh Yes, separate power ground return. 2 oz copper traces. Russian 0.033 - 0.056uf k71 styrenes (what ever I can get at an earthly price) as close to the power pins as possible. Next to those 1uf pp. Also 220uf panasonic FM//1uf PP from pos rail to neg rail to help with supply common mode. I could go on.
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It doesn't translate to the listening experience. The theory may look good on a chalk board, I understand.
Morinix, are you really using the LT1358 with 10Vpp input? if not, then maybe you should check that nice chart with "slew rate vs Input level" and let us know the slew rate at the actual input level.
The part that does not line up with your thinking is that every time I used a faster device, be it in a design of my own or a modification of an existing unit that same result happens. This has played out since the early 90's when I was exposed to this philosophy.
Well since I have nothing to listen to nor do I know what "musical drama" is I could only go by the numbers and recommend an even noisier op-amp with 9000V/us. What in fact is the difference between T&M and taking a single number off of a datasheet as a measure of performance.
BTW there's a 40,000V/us 6 GHz op-amp coming soon.
Feel free to PM me to talk about layout details, it'll get way too arcane for this thread I fear.
DIP adapters... and what are those ceramic caps for? If the polystyrenes are your decoupling caps...
Faster determined by slew rate or GBW? Degenerated LTPs give faster slew rates and as a result of the degen they have more linear front-ends. Ditto JFETs.
Except you're just plain wrong and too ignorant to see it. The LT1358 is not even a faster device in all cases. Even Kirchhoff (!!) is trying to explain to you.
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It's a lot slower with a MM cart level input. No similar chart on the LM4562 that I could see on a quick scan. I would guess that it would also be much slower than the 15v/us (OUCH!) minimum on the spec sheet. So if the LT1358 is sub 100v/us on a millivolt input what would the SR be on the LM4562 with a millivolt input?
Come back when you understand the difference between small signal and large signal bandwidth.
I don't know. Nor does TI care to tell us. They have some 10 pages of THD diagrams though. I guess their target market were those obsessing on THD 😀
And here, ladies and gentlemen, is one example where the measuring instruments come into play - for the right reasons. Where spec sheets are incomplete and / or innacurate.
They need to sell like anyone else. A mile long spec sheet will usually go unread.... until things like this happen.
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Hey, I'm not the one designing and selling audio equipment based on a singular datasheet number that I don't even understand.
Hey guys. Next time you're picking on me, at least have some balls and do it like the gentleman above. Allusions to ignore lists and such are for sissies. 😉
morinix, just for kicks, roll in some LM358..... that one would surely produce some unique sound... tee hee...
I got that impression too but to be fair they also have more plots of PSRR than any other opamp I've seen. I guess their customers find graphs with impressive lines on greatly reassuring 😀
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Back to the mud slinging (let's not). The above statement shows a fundamental mis-understanding of what's going on. Both amplifiers are first order integrators so the input error signal and it's linearity vs rate of change of the output is what is important. Slew rate is an expression of the limit of rate of change of the output. Slew rate as a function of input (especially at the mV level) is meaningless.
You can do this on the bench with a high gain buffer measuring the input differential while reproducing a tri-wave, very educational. You even get to apply Kirchoff's law. 😀
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