[LAD] Fw: Re: Some questions about the Jack callback

Will Godfrey willgodfrey at musically.me.uk
Sun Sep 21 15:38:58 UTC 2014

On Sun, 21 Sep 2014 07:50:45 -0700 (PDT)
Len Ovens <len at ovenwerks.net> wrote:

> On Sun, 21 Sep 2014, Fons Adriaensen wrote:
> > Almost all lossy audio compression schemes are based on this.
> > So one way would be to explore in how far you could parametrise
> > e.g. an ogg or mp3 decoder and turn it into a synth engine.
> The expected latency with ogg or mp3 is 200+ms, the Celt end of Opus might 
> be a better choice (5ms). Even Silk is probably higher latency than a 
> sound generator wants. The latency listed for all these codecs is the whole 
> chain: encode plus transport plus decode. OPUS gets it's lower latency in 
> some cases by throwing away missing packets that ogg might be able to 
> wait for. So it is possible that the decode part of all of these might 
> have useful ideas.
> --
> Len Ovens

Sheesh! I'm away for one day (live folk music actually) and the thread
explodes :o

I can follow this in outline, although not the finer details, but my greatest
concern is how would you go about proving there was no noticeable difference
to the listener? With all the interaction possibilities I suspect there are
rather a lot of corner cases.

On a slightly divergent point, someone tried to correct a spelling mistake in
Yoshi that made a saved parameter invalid, but of all the sounds in all the
banks I have, this made a very slight but noticeable change to just one
instrument. Had it not been one I use frequently I might still not have
realised it.

I'm also reminded of the situation when the web was fairly new and people would
make copies of copies of jpegs. The differences only got noticeable about 3
steps down, but by then it was too late. The damage had been done.

When I show off my music to others, the sound is the first comment (I could
wish otherwise) so personally I'm rather twitchy about anything that might
alter that, and as a musician I'd rather spend out for a more powerful computer
than have a more efficient but possibly compromised mojo.

... of course, as an engineer I would like the greatest efficiency possible -
fortunately I don't talk to myself :)

Reading this back, it seems rather like a rant. I'm sorry, but 'our' sound has
become critical to my compositions.

Will J Godfrey
Say you have a poem and I have a tune.
Exchange them and we can both have a poem, a tune, and a song.

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