[LAD] Alpha testers wanted !

Fons Adriaensen fons at kokkinizita.net
Tue May 1 16:17:50 UTC 2007

Hello all,

I'm looking for some alpha testers for a small application
that I wrote to test the DSP core of Aella, the convolution
and reverb processor announced at LAC2006.

If you are using Jace then Jconv will be familiar as it uses
the same configuration files. 

Candidate alpha testers please drop me a line !

>From the README:

Jconv - Alhpa release - for testing only.

Jconv is a Convolution Engine for JACK using FFT-based partitioned
convolution with multiple partition sizes. It's a command line version
of what will be the core of Aella, but without the special reverb
feautures, preset management, reverb envelope editing etc. that
Aella will have.

Jconv uses a configurable smallest partition size at the start of the
impulse response, and longer ones further on. This way you can have 
long impulse responses _and_ minimal or even zero delay at a reasonable
CPU load. This would be impossible using just one partition size.

Processing for partition sizes larger than Jack's period size is
delegated to up to five threads running at real-time priorities just
below that of Jack's audio threads. CPU load generated in such threads
will _not_ show up in Jack's DSP load figures.

If you set the smallest partition size equal to JACK's period, there
will be zero processing delay. Otherwise the processing delay is 
2 * smallest_partition + period_size.

Jconv will do any convolution matrix up to 64 inputs by 64 outputs,
as long as your CPU can handle it. It doesn't waste any memory or
CPU cycles on empty cells in the matrix, nor on empty parts of an
impulse response. Maximum length for each convolution is 30 seconds.

Jconv can easily generate 100% CPU load at real-time priority. This
will in most cases not stop audio processing, as the load will be at
lower priority, but it will lock up everything running at normal
priorities such as your terminals or desktop. Don't panic - jconv
will detect the situation and bail out after a second or so.


Follie! Follie! Delirio vano è questo !

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