I am sure other industries using standard T&M gear and methods are also missing this critical circuit misbehavior from asymmetrical waveforms?
Regarding polar coupling caps - pretty sure there are millions of happy consumers of audio devices using them without a problem. No doubt including some Stereophile Class A+ gear in the five-figure price range. I just don't see the practical impact, even if they are obviously not ideal.
Richard, these all seem very testable, and frankly your description of "asymmetric" signals is a DC bias applied to any sort of other test signal. What's so revolutionary about this?
Now the whole music is different to sine waves is hocus pocus. Any basic signals book from your soph/junior level EE curriculum goes through this stuff stuff rigorously.
Now the whole music is different to sine waves is hocus pocus. Any basic signals book from your soph/junior level EE curriculum goes through this stuff stuff rigorously.
I think that it is appropriate to put in one of the Hirata papers also, so people can see different waveforms that are hard to produce with just sine waves, and are asymmetrical in character. The Hirata test is one of the most interesting that I have ever found that is usually unknown to typical engineers. I have tried it, and it works!
I am sure T&M gear wouldn't use the cheap and poorly made, unstable, unreliable parts we accept in Audio gear.
Yes, lots of people like music from what ever. so what?
THx-RNMarsh
OK. So? Do asym tests on some variety of real, physical amp topologies, then. Throw in some tube designs also.
What if the levels of distortion are different for + and - asym waveforms? And, what if the THD meter shows a lower distortion average of the two?
See if there are some new insights. An ARB gen could be useful. Go for it.
Just sayin'
THx-RNMarsh
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I'm not the one proposing its utility or some kind of new insight. Burden of proof and stuff, right? Especially since I a.c. couple my gear, nor power my equipment off multiple circuits to get huge potential differences between boxes.
Heck, for audio distortion of power amps, I struggle to see what a good 19+20k imd doesn't already show. Slap a dc step over common mode range if it makes you feel better.
You should try a couple of Hirata waveforms, DPH. You can READ the engineering note, can't you? It should be easy for you to digest.
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And if you read the hirata paper you find it's a pulse train and some Fourier transforms, ironically showing the spectral composition of the pulse train in terms of sinusoids. Worthwhile when the kind of capture and transforms weren't as easy as now, and I need no disrespect by that. How we test electronics has moved past 1981. So what is this telling us that we don't see from looking at the spectral composition of distortion products? Or triangle waves? Sure thd is less than useful as an ensemble measure, but I'd hope we've moved past that.
I don't see what I'm missing.
I don't see what I'm missing.
Just try it with such or similar waveforms. Then FFT it, if you like. Are there differences with change in polarity? If there are differences, what in topology is causing it.
I would use a lower distortion threshold, though.
-RM
I would use a lower distortion threshold, though.
-RM
Have we accidentally fallen in to hades where, instead of the boulder rolling down the hill each night the same discussion comes round again?
Wow! You have a source (and cables) which can deliver infinite bandwidth. You also have amplifiers which look at the whole waveform and are clever enough to cope with its complexity, while the rest of us have to content ourselves with simply looking at the current signal value and some memory of the recent past.john curl said:
Generating an asymmetrical waveform is easy: just add some second harmonic. Most systems will do it for you without you asking.
Serious Fourier denial going on here. Did you sleep through your maths lectures?john curl said:
Agree. It's about interpretation and translation into fulfilment of wanted position. At least as long as it is about carrying a waveform in a none mechanical representation. I don't believe that the current 2 channel paradigm is up to the snuff. Snuff, being able ro reproduce a live event at home. But it aint the handling of the vawe-form in terms of A/D->D/A->amplification that is the main problem - here we could still improve by not making the mistake analysing a quite gross average of the signal time-vise (typical freq. response/distorsion) but rather look at the envelop e.g. wavelet analysis.
We need to re-think the usage and number of the recording/replay electro-mechanical front ends - especially spatiality, i.e. the whole basic system rec/rep. architecture. The lack of symmetry is cumbersome. Thats where the real barriers are I believe.
//
Run for shelter: A serious attack of the commando of the objectivists is happening at the moment. Supported by the usual shelling of disrespect and immutable certainties.
The electrical bit is done and dusted surely? (Unless some forms of coloration do actually help with the perception) It's interesting as an exercise to pursue perfection, and no reason not to, but no great advances lie there?
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