[Coco] Including an SSC

jmlaw at iprimus.com.au jmlaw at iprimus.com.au
Sun Oct 12 20:52:25 EDT 2014


Simon Jonnasen wrote:

>The AY chip in the ssc is simple but it's not limited to simple sounds. The
>simplicity is a great thing for games in order to reduce the cpu time
>required to generate the sound. That said, it's also capable of some really
>funky sounds and effects with software trickery (at the expense of added 
>cpu
>time).

Totally realize the point you were making as you'd shown me the vids before, 
and a valid point too.

>From my view, when I read the manual the first time it seemed overly 
technical in some regards but also somewhat over-simplified. Reading it the 
second time I took notes of the various bits I needed to know. It also 
switches between speech and sound so it takes a bit to get a clear picture 
of how it works. So trying to explain it in the simplest form I could think 
of may have given some the impression it's too simple. Oops :)

It was only through studying the NES background music that I worked out the 
"adjust amplitude at vsync" to refine the tone. The manual doesn't teach 
that, nor do the included hardware envelopes give you anywhere near that 
control.

So for anyone who has read the manual and just ended up a bit dissatisfied 
with beepy tones, the manual doesn't explain the potential and probably also 
intentionally simplified in some places for basic programmers.

I think the software in the Orch-90 does a similar thing re amplitude 
control to shape the tone so wether you use the CPU to generate the tones or 
the AY, a similar effect is possible.

I'm no audio expert and don't claim to be. I just studied it intensively in 
the area of my interest and share here what I've learned in hope it might 
give someone who was a bit dissatisfied with the sound capabilities after 
reading the manual, something new to try.

New in the sense it's not in the manual, not that it's never been done 
before :)

Jason 



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