Re: [hatari-devel] Bad sound in Monscape demo

[Laurent Sallafranque <laurent.sallafranque@xxxxxxx>]

Hi,


As you're speaking of sound glitches, I have encountered another problem 
(it may be the same as you describe, but I prefer describing it as a new 
problem for now).


In my new code, I've made a sound mixer.

I've configured the Falcon to play 50066 hz mono 8bits sound.

I use 22050 hz samples.


When I feed my inner buffer (in my program, I take the 1st byte of the 
"sample1", then I copy the first byte of the "sample2", then the 2nd 
byte of the first sample, ...

The sound looks like : 12121212121212...

If I have only one sample, the sound looks like 1010101010...  I feed 
the "second sample" with zeros.


On the falcon, it sounds perfect, no problem (I know my samples are 
playing a bit slower than on my PC, but the sound is OK).

Under hatari, the sound plays OK, but after some times, it starts to 
glitch and crackle, and again, after some time, it becomes good again, 
.... It's a cyclic event (maybe a sinusoidal event, when sound goes from 
perfect to glitchy).


I think some Falcon demos with glitchy sound are using this 0 0 0 
technic to mix.


I don't know if this tells something to anybody, and if there's a way to 
improve the emulation here.


I just share not to forget it later and in case this ring a bell to someone.


Regards

Thadoss.




Le 05/12/2022 à 20:06, Eero Tamminen a écrit :
> Hi,
>
> I have bad sound in (Sommarhack 2022) "Monscape" demo:
> https://www.pouet.net/prod.php?which=91818
>
> With latest Hatari Git version.
>
> Drums and bass in the music are very scratchy compared to the clean 
> sound in the demo video:
> https://www.youtube.com/watch?v=wSk9JtcL4TE
>
> This is not a regression, I hear same bad sound also with Hatari v2.3.1.
>
>
>     - Eero