[PD] latency solutions... and then some

[Jeffrey Concepcion]

Thanks for the suggestions, i'll deffinately be looking into your
suggestions (i'm not familiar with some of the terms ). For now i must deal
with what i have at home, which is an acer netbook w/ windows Xp @ 1.6 GHz,
1GB RAM btw! No external soundcard as of yet. i should get (in theory) a
similar result to Pierre's so i'll be trying that approach for now. i also
have access to new macpros at my university and a motu 8 channel interface
so i'm hoping for much better results there.

As far as upgrading goes, i'm considering building a pc dedicated to my
audio needs, probably running a linux distro, any recommendations would be
much appreciated. Perhaps i should include the dedicated DSP board that
Derek mentioned. Can those be used to process pd patches?

On Sun, Jan 31, 2010 at 9:20 AM, Pierre Massat <pimassat at gmail.com> wrote:

> Hi Jeffrey! I ve been trying to minimize latency in Pd for a year now,
> experimenting with various OS and hardware. I m using Pd for the same
> purpose, that is live processing of electric instruments (mainly a guitar).
> I would recommend using a Linux distro, because they have "realtime"
> kernels, and the JACK server, plus you can get the hid object in Pd (which
> does not exist on windows). If you want to play live you want to go for
> latencies below 7 or 6 ms. I get a 5 ms latency on an old Dell laptop (1
> Ghz) with the latest Fedora with the CCRMA realtime kernel.
> I can also give you a couple of hints about the interface (I personnaly
> have hacked a cheap gamepad and it works great). You can reasonably expect
> to get a low-latency live set at a very low cost, provided that you have a
> quite recent laptop to work with.
>
> Pierre
>
> 2010/1/31 Derek Holzer <derek at umatic.nl>
>
>> "Unnoticeable" latency usually refers to the musician not noticing the
>> difference in time between when they press the key and when the sound comes
>> out. Any time you add a delayed signal to the original signal, you will
>> notice it. The "slap-back" happens at longer latencies, but at shorter
>> latencies you will hear *very* noticeable comb-filtering. And since no
>> computer-based solution is latency-free, I think you need to re-examine what
>> you are expecting Pd to do. Either that, or go with a dedicated DSP board
>> (and learn the accompanying programming!) which would give you a more
>> guitar-pedal-like "zero-latency" system.
>>
>> Maybe Marco Donnarumma could give a few words here on processing
>> instruments live. His set uses an electric bass through Pd. My guess is that
>> even the un-processed signal goes through Pd to avoid echos or comb
>> filtering due to latency.
>>
>> Best,
>> Derek
>>
>> Jeffrey Concepcion wrote:
>>
>>     * in terms of processor capacity, hardware, and sound card
>>>
>>>      configuration, what would be the minimum requirements to achieve
>>>      unnoticeable latency (not hear the affected signal as a slap-back
>>>      type of effect)? i've read that 11ms can be achieved and is
>>>      unnoticeable.
>>>
>>
>> --
>> ::: derek holzer ::: http://macumbista.net :::
>> ---Oblique Strategy # 18:
>> "Balance the consistency principle with the inconsistency principle"
>>
>>
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>
>


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