[LAD] Audio effects on Android

Olivier Guilyardi list at samalyse.com
Mon Feb 28 17:02:57 UTC 2011


(split from: RDF libraries, was Re: [ANN] IR: LV2 Convolution Reverb)

On 02/27/2011 02:13 PM, Stefano D'Angelo wrote:
> 2011/2/27 Giuseppe Zompatori <siliconjoe at gmail.com>:
>> 2011/2/27 Stefano D'Angelo <zanga.mail at gmail.com>:
>>>
>>> In the FAQ they say it's actually some sort of preamp... but well, I
>>> can't provide hardware anyway.

>> I was merely pointing it out as I don't think there is currently any
>> other way to do it.
>> Connecting the guitar directly to the phone with a simple plug adapter
>> would probably sound meh.

I've had several users report success in using various microphones plugged into
their Android device, with these adapters:
https://www.kvconnection.com/Articles.asp?ID=165

I haven't tested that, but I think that it should work with a guitar.

>> Unless Google wants to add support for external USB sound cards to Android? ;)

There's no plan for this AFAIK.

>>> I don't even know if I would charge for such plug-ins and/or release
>>> them as closed source. Ideally, I would release them under GPL and
>>> accept donations, but have no idea really. Actually there are a couple
>>> of plug-ins I could really charge for since they are really beyond
>>> state of the art and suitable for scientific publications (indeed,
>>> that's why I'm developing them). They are physics-based simulators: a
>>> fully parametric tube amp + eq + output transformer + loudspeaker +
>>> air impedance, and a couple of diode clippers (one is
>>> tubescreamer-like) - still some pieces are missing at the moment (new
>>> triode model in the making, oversampling not yet in place, opamp model
>>> not yet serious).

This is entirely up to you of course, but I think that there are some
compromises. I am not sure that it would work in this case, but for example, one
could consider releasing an LV2 plugin under the GPL, and make a paid version
for Android which includes a nice UI. Fancy UIs can involve costs, such as
working with a professional designer, etc..

>> And I would prefer GPL'ed plug-ins and be willing to donate, I don't
>> think there are many options right now on Linux, I dislike rakarrack
>> and guitar_ix, and find CAPS* so so.

Some app developers accept donations. It's even the case of some of the most
popular Android music apps. They usually release the app freely, and they have
another paid "app" which actually provides nothing but a way to donate.

> Well, they say guitarix has improved, yet the last time I was all but
> satisfied with it. You may want to take a look at invada plugins, if
> you haven't already.

So far, I've had my intern select more "generic" effects, such as reverb,
compression, delays, etc.. It needs some more work on the guitar side.

>>> However, correct me if I am wrong, I don't think most Android
>>> platforms would be suitable for live processing (latency), but only
>>> for recording (what about quality?).

Latency is terrible. Expect about 100ms for input and for output as well. This
situation is one the main reasons why we created the Andraudio mailing list [1],
dedicated to audio development on Android, but also possible audio stack
patching/improvement.

In the current situation, applying effects in realtime isn't possible on Android
because of such latencies. But it's of course possible for post-processing, and
that's what I'm working on.

The quality can be rather good. It's nothing like desktop gear, but it's ok for
composing on the go, to catch ideas whenever/wherever they come from, record a
piece of guitar, add some effect, and send it right away to your band...

[1] http://music.columbia.edu/mailman/listinfo/andraudio

--
  Olivier




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