[PD-ot] how low (latency) can you go?

[Tim Blechmann]

hi hans,

nice selection of papers to read before the morning coffee, however i've
got some comments on them:
	
> "As already noted in 3.1, the precedence effect says that sounds are  
> perceived as coming from a single source when they occur within 25-35  
> ms time window (Haas, 1949).

right ... but in a setup with microphone->computer->speaker, there are
two sources, the original source, and the processed source

> "[T]he perception of the latency between an user action and the  
> corresponding reaction... shows a very high degree of precision: it  
> was shown that variations in feedback delay of 20ms are, although not  
> consciously noticed, compensated for..."
> 
> This article has some good info on jitter too.
> 
> http://gsd.ime.usp.br/~lago/masters/latency-paper.pdf

also this covers the effect of one sound source, doesn't it?


> "Since sound travels at about 1 ms per foot, latency of 7 ms is  
> roughly equal to the maximum separation between members of a string  
> quartet.  In practice, latency of 10 ms is generally imperceptible,  
> as long as the variation in latency (i.e. jitter) is kept small."
> 
> http://www.midi.org/about-midi/tutorial/tutor.shtml

hmm ... they are referring to one sound source ...


> ---------------------------------------------
> For realtime games (e.g. FPS, RTS), latencies greater than 50-75ms  
> are noticeable.  Upper threshold of manageable latency is 100-200ms.  
> (paraphrase)
> 
> http://www.ibr.cs.tu-bs.de/users/wellnitz/papers/netgames2005/ 
> netgames2005-talk.pdf?backurl=%2Fcm%2Fbib.html&lang=de
> 
> http://www.ibr.cs.tu-bs.de/users/wellnitz/papers/netgames2005/ 
> netgames2005.pdf?backurl=%2Fcm%2Fbib.html&lang=de
> ---------------------------------------------

... and these papers don't refer to audio at all ... more control data
for video frames ... interesting to read, but they don't have anything
to do with what we are talking about

> So, my whole point with all this is to say that you really don't need  
> to worry so much about latency to have a very playable computer  
> instrument.  

, if you are not going to do realtime processing of audio material


> So if you want to make art, spend your time making art  
> instead of getting a few less milliseconds of latency in your setup.

right ... it's perfectly fine to play piano pieces on a broken piano
with an open window (http://www.lcdf.org/indeterminacy/s.cgi?4)

cheers ... tim

--
tim at klingt.org    ICQ: 96771783
http://www.mokabar.tk

You can play a shoestring if you're sincere
  John Coltrane
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