11 Dec
2003
11 Dec
'03
7:18 a.m.
hello,
i remember that some time ago there was some discussion about
bandwidth limited waveform generators. my question is: did
anybody compare the various implementations, and does anybody
have an idea what would be the fastest? (square, saw)
maarten
11 Dec
11 Dec
7:45 a.m.
On Thu, Dec 11, 2003 at 12:16:27 +0100, Maarten de Boer wrote:
hello,
i remember that some time ago there was some discussion about
bandwidth limited waveform generators. my question is: did
anybody compare the various implementations, and does anybody
have an idea what would be the fastest? (square, saw)
I use a set of tables with increasing numbers of partials
(http://plugin.org.uk/src/util/blo.h, .c) for tri, squ, saw. Its pretty
basic but it works and its fast. It handles stuff like partial pop-in
problems for you.
I use a slightly evil SHM hack to share the tables betwwen plugins and
applications that use them, which should reduce the memory/cache hit.
There are other techniques that should have a smaller memory footprint, if
your not worried about some aliasing, but I've not tried them.
- Steve
8:15 a.m.
On Thu, Dec 11, 2003 at 11:43:02 +0000, Steve Harris wrote:
On Thu, Dec 11, 2003 at 12:16:27 +0100, Maarten de
Boer wrote:
I should also point out that Mike Rawes has a similar implemntation, but
he has PWM on sqaurewaves IIRC. I dont know if/what the other differences
are.
- Steve
hello,
i remember that some time ago there was some discussion about
bandwidth limited waveform generators. my question is: did
anybody compare the various implementations, and does anybody
have an idea what would be the fastest? (square, saw)
I use a set of tables with increasing numbers of partials
(http://plugin.org.uk/src/util/blo.h, .c) for tri, squ, saw. Its pretty
basic but it works and its fast. It handles stuff like partial pop-in
problems for you. 
8:49 a.m.
On Thu, Dec 11, 2003 at 11:43:02AM +0000, Steve Harris wrote:
I have anti-aliased dirac pulse (flat amplitude spectrum) and sawtooth
(1/f amplitude spectrum) plugins that will be released probably tomorrow
on the Alsamodular site. A square / rectangle / triangle one is 'under
construction'.
They use interpolated dirac pulses and integrals thereof. Aliases
are below -80 dB for F < Fs/6 (this covers the fundamental frequency
range of most instruments). Memory footprint is very small, and the
code is quite simple and fast.
--
Fons
On Thu, Dec 11, 2003 at 12:16:27 +0100, Maarten de
Boer wrote:
i remember
that some time ago there was some discussion about
bandwidth limited waveform generators. my question is: did
anybody compare the various implementations, and does anybody
have an idea what would be the fastest? (square, saw)
I use a set of tables with increasing numbers of partials
(http://plugin.org.uk/src/util/blo.h, .c) for tri, squ, saw. Its pretty
basic but it works and its fast. It handles stuff like partial pop-in
problems for you.
7604
days inactive
7604
days old
linux-audio-dev@lists.linuxaudio.org
3 comments
3 participants
participants (3)
-
Alfons Adriaensen -
Maarten de Boer -
Steve Harris