John Curl's Blowtorch preamplifier

[serengetiplains]

The term "echo" communicates sufficiently to me, as does "ghosting." In case I'm being misinterpreted again, those terms should not be taken literally to imply that a smaller Mini-Me version of the originating AC signal pops out like the return of sound waves in the Grand Canyon. I personally wouldn't be surprised, as seemingly must be the case, that dielectric voltage absorption and release are non-linear in frequency and time domains, among others.

[Steve Eddy]

Originally posted by john curl
It is signal AFTER the original input has gone, and there should be only silence.

If that's what's actually happening, then it should be pretty darned easy to demonstrate it.

So has it been demonstrated in the more than 20 years since you wrote about it, using the term "echo"?

se

[john curl]

Of course.

[Steve Eddy]

Originally posted by john curl
Of course.

Oh, well then let's see it. I'd love to see these "echos" trailing the original signal after the original signal has ended.

se

[poobah]

Nothing that happens here, because of DA, can be nonlinear; at least on a discussion of second order (FORGET THIRD FOR NOW)effects. That is because the components and the best models of DA are linear. That is not to say that many linear effects can't cause audible stuff/flaws.

[Steve Eddy]

Originally posted by poobah
Nothing that happens here, because of DA, can be nonlinear; at least on a discussion of second order (FORGET THIRD FOR NOW)effects. That is because the components and the best models of DA are linear.

Quite so. And certainly nothing that will have an "echo" signal following behind the original signal.

That is not to say that many linear effects can't cause audible stuff/flaws.

True.

se

[poobah]

Give Serengeti a break,

I'll beat up cable guys all day long... just for fun... R = R. But this cap thing is not all hooey. Tom may choose words which don't suit you, but he has not implied, and in fact has spoken to the contrary, that there is no "echo" i.e. complex AC waveforms" stored" in DA.

I think he's out there sometimes, but unlike so many of us, he has taken the initiative to have prototype caps built. Except for his ears, he may not have the the toys to subject these prototypes to more "acceptable" methods of testing.

Study a DA model, then ponder what it does to an audio signal. Google "capacitor soakage" and read. And then don't tell me Bob Pease or serengeti is full of ****. I'm sitting on the fence here. I have a plan and things I want to learn for myself. There is one crucial measurement/aspect of DA that has been overlooked.

[lumanauw]

Hi, Mr. Curl,

I wanted to ask your opinion about Snubber.
People put snubber (1ohm+100nf, series) in parrarel with big bank capacitor (like 10.000uF). In what way this snubber affects or not affecting the sound of an audio amplifier?

[Steve Eddy]

Originally posted by poobah
Give Serengeti a break,

I did. Back when I said "Ciao."

I'll beat up cable guys all day long... just for fun... R = R. But this cap thing is not all hooey.

Never said it was.

Tom may choose words which don't suit you, but he has not implied, and in fact has spoken to the contrary, that there is no "echo" i.e. complex AC waveforms" stored" in DA.

But John, who I was actually referring to, did say as much:

It is signal AFTER the original input has gone, and there should be only silence.

If we're talking about audio here, then "signal" is indeed a complex AC waveform.

Study a DA model, then ponder what it does to an audio signal.

I have.

Google "capacitor soakage" and read.

Done that too.

And then don't tell me Bob Pease or serengeti is full of ****.

I won't tell you that Bob Pease is full of ****.

I will tell you that I have disucssed the issue with him.

I'm sitting on the fence here. I have a plan and things I want to learn for myself. There is one crucial measurement/aspect of DA that has been overlooked.

What measurement/aspect of DA is that?

se

[poobah]

I won't tell you about the "measurement", your very cranky right now, it's extraordinarily obvious, and might make me a buck or two.

In the case of "john", a slowly decaying DC potential may represent distortion... it's all about where you draw the line between DC and AC. that is not only about fundamentals, it is about spectral (harmonics) as well.

No one here has described caps as short term tape delays, although you have chosen to assume that for the sake of rudeness.

Oh, and next time you talk to Bob, tell him to call me, please... I lost his number and we were supposed to camping...

(jeeze!)