John Curl's Blowtorch preamplifier part II

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Honestly, I think you need to re-read that. That statement advocates that absolute frequency is not the most important when it comes to choose a clock to drive a digital audio system.

If all at this forum had this white paper as basis for understanding "jitter", life here would be a better place.

http://www.grimmaudio.com/site/assets/files/1088/picoseconds_or_ppm.pdf
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I did and it remains wrong imo, second para, after which I can't read on. Whilst I agree that absolute frequency is unimportant - the pitch at which we tune is just a convention - this is not where the error is. The mistake is that the equate the effect of a clock running fast (which will increase pitch) with a small elevation of the temperature in the concert hall (which will not change pitch, 41 Hz conducted through warm air is the same as conducted through cold air, it just will arive a little sooner).
 
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I did and it remains wrong imo, second para, after which I can't read on. Whilst I agree that absolute frequency is unimportant - the pitch at which we tune is just a convention - this is not where the error is. The mistake is that the equate the effect of a clock running fast (which will increase pitch) with a small elevation of the temperature in the concert hall (which will not change pitch, 41 Hz conducted through warm air is the same as conducted through cold air, it just will arive a little sooner).

If it would be true, it would be the same as saying that when a car goes faster, the hood arrives earlier than the boot :D

(Waiting now for the first one who will point out that the hood ALWAYS arrives before the boot, thereby showing he didn't get the issue :):))

Jan
 
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Yes, analogies are at best a crutch to help you get moving. But analogies are not a 1:1 correspondence to the issue at hand.

One technique to kill a conversation or line of reasoning that you often see applied here is to come up with a special case where the analogy breaks down, and then declaring the original case wrong or invalid.

And of course, you can ALWAYS find a special case where the analogy breaks down.

It's a pity because analogies can be very helpful to explain a complex issue; and after you Get It, you no longer need the analogy.

Jan
 
Surely we bludgeoned this to death elsewhere, to the point of conclusion that for audio risetimes and normal length cables we can safely forget TL effects and there might as as well be no such thing as mismatching......

The mistake is that we never "suddenly" apply 2mV in audio. Well, 'sudden' in audio is relatively slow in the scheme of things more to the point.

That as a little TIC. :D
 
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