John Curl's Blowtorch preamplifier part II

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If you look at this page it seems that it is easy to end up needing to keep 64 bits of precision:

IIR Filter Design, Software and Examples
Look at the 10 pole chebychev about 1/3rd or so down... in theory the bit depth does keep increasing every multiply, but careful analysis or trial and error will show where you can throw away the extra bits as not mattering to the end result.

Which was what I was clumsily getting at. The referenced paper was 'shock horror you need more than 16 bits to do DSP', but with a poor example (master gain). Wasn't sure if he was over dumbing down for his target audience or just didn't have a good grasp on what was going on under the hood.
 
You already have sound cards that deliver -130 dB noise levels ref 1V and I have seen better. - Pavel has shown some plots here. As Scott has just pointed out, modern PC CPU require 100 A. They are fed from a buck converter usually running at c. 300 KHz with the mosfet switches transitioning in a few ns.

Noise? What noise?

;)
Good points - of course, this environment is well known to the designers, they've had decades to come to grips with the subtleties of getting good numbers; a good example of how engineering will always achieve a good result if they can do many iterative rounds, over many versions, to get it as good they see fit.

However, a brand new design, in a purely audio context is something quite different ... I saw the DEQX SMPS, a tiny bareboard thing, like something pulled out of a wallwart - it didn't inspire me, :)!

Conventional noise is not the real problem - the headache with digital sound is that insufficient engineering leads to an "inaudible" layer of grunge which flattens, removes the essential "sparkle" and depth of the sound - one can get quite a shock when this is removed - "bloody hell!!" could be the reaction ... :D.
 
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When does one dither? Do you dither each recorded track? Do you dither again when you mix tracks? Do you dither everytime you do just about anything which could cause distortion... besides dropping from 24 to 16b. Is there any difference between dithering the music once and many times all along the way in processing the music? And, finally, what do the majority of recording/producing people do (regardless of what is best) in practice regarding dithering?


THx-RNMarsh
 
And, finally, what do the majority of recording/producing people do (regardless of what is best) in practice regarding dithering?
THx-RNMarsh

In any field studying what less than competent people do has little practical use. I get tired of saying this, if it's your job learn the art and practice it. What is best is not rocket science, it's not like anyone is hiding the theoretical underpinnings. I, at times, share Mr. Widrows feelings.
 
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I should have learned my lesson by now, but what refinements would that be?
Well, grasshopper ... a good engineer if told that a product is not up to scratch assesses that for himself, and progresses from there ... :).

Klipsch products are often accused of being raucous, raw, having in your face sound. IME, a system will often go through that phase, prior to achieving convincing sound - it's almost a "necessary" step ... save me from systems having "refined" sound, :rolleyes:, all the time ...

The "refinements" in the speakers themselves would be all the usual things, mentioned in "sensible" posts on diyAudio over and over again - improving connections, carcase deadness, getting rid of or bypassing all the cheap shortcuts that the manufacturer uses to get the costs down, and make the unit easy to manufacture.

But what the Klipsch will do is expose other system weaknesses more clearly - because they're easy to drive, they will go loud with no effort at all ... and all those little problems in the overall system that weren't so obvious before are now thrust into your lap ... either get yourself a speaker that "hides" those issues, or fix them ...

Pedant, signing off for now.
 
ahh, cheaply made horn has lots of horn distortion, fix it with amplifiers. Of course, why didn't I think of that.
Well, the one I listened to didn't have this notorious "horn distortion", whatever that is - I had a recording with high energy blues, very well recorded - and the recording sounded like the recording: the vocals were right, the cymbals were right - you know, it sounded pretty "real" - must be that cursed "horn distortion", will have to fix that ... mutter, mutter ...

People keep thinking that if you have a system that can go loud, that you will run it so it sounds LOUD - sorry, it doesn't work that way ... what it really means is that whatever is playing sounds natural, a crashing piano chord doesn't fall into a heap, it nicely fills the space just like the real instrument would do - you can do normal things in the room, or house, without concentrating on the sound or music, and it just feels 'right', all the time.

That's the point of the exercise ...
 
Gaawd, let's "solve" some things in one fell swoop ... Digital Problems, Practical Solutions - there, that should keep 'em quiet for a bit ...

Sampling is a simple modulation process —an amplitude modulation (AM) process, to be precise. Just like AM radio, it can convey audio accurately from one place to another via an appropriate medium. We all listen to the radio and know it works, so why doubt exactly the same process when it is used in digital audio equipment?

Doo doo Frank plain and simple. Why do you post this BS? You waste everyone's time, the OP had to work at making such a carefully crafted statement that was so wrong.
 
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"Doo doo Frank plain and simple. Why do you post this BS? You waste everyone's time, the OP had to work at making such a carefully crafted statement that was so wrong."

Indeed. I posted about a year ago about this trolling. That IS what it is. Obsessive concentration on his own agenda, no matter what the actual thread is about. Many "ideas" in "quotes" so that one has no "idea" what he is "talking" about.

I am very fed-up about it. I try not to react but it is really spoiling my enjoyment of DIYAudio.

I ask the moderators to find some way to get him to STFU!
 
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