Re: [Octal-dev] audio in linux

[Guenter Seethaler]

>>>>> "Neil" == Neil Nelson <address@hidden> writes:

    Neil> Johan Rydberg wrote:
    >> In main.c, line 58:
    >> 
    e-> block_size = 8820;
    >> 
    >> I want to change this, to for example:
    >> 
    e-> block_size = 2205;
    >> 
    >> Why?  To reduce latency from 200ms to 50ms. But when I do this,
    >> everything sounds very different.
    >> 
    >> Any ideas?

    Neil> You appear to be using the prior release as the new release does
    Neil> not have this line in main.c.

    Neil> As a note, I just compiled the new release and no sound was generated
    Neil> by executing octal-test.  There is likely some item previously 
mentioned

    Neil> that slipped by my attention.

    Neil> Back to main.c of the prior release....  At the top of main.c there is
    Neil> the
    Neil> line

    Neil>   #define BLOCK (TICK/5)

    Neil> which does not appear to be substituted elsewhere and becomes the
    Neil> 8820 in

    e-> block_size = 8820;

    Neil> Just to be on the safe side, I changed both of those lines to

    Neil>   #define BLOCK (TICK/20)

    e-> block_size = BLOCK;

    Neil> which gives your 2205 result above.

    Neil> The only difference in the resulting sound that I could tell is that
    Neil> the notes are executed faster (a faster tempo, 4 times as fast).
    Neil> Since the computer is working a little harder by executing the
    Neil> update functions at a faster rate, you could possibly hear clicks or
    Neil> breaks, as compared to the initial block setting, as the computer
    Neil> pauses the output to catch up.

    I just downloaded the last version from alpha.org
.


Fragment of Main.c (from octal-alpha-0.3a) Revision 1.11

    e = create_engine();
    e->block_size = 8820; /*  This is a hack in my opinion */

change it to:

   set_timings(e, 2205, 4, 120) /* set_timings(engine, blocksize, tpb, bpm) */
 
and it should work proberly. I coud not test it, couse i sit in front
of a sun. 
The speed should be the same as before. 
It will start clicking/breaking when the blocksize gets to low.


Guenter