How do you use SCSP DSP Modulation Effects?

Hi! I was messing around with the SCSP DSP to see what you could do with it and I got stumped reading this:
Screenshot (247).png

I used the modulation voices it says to include but I can't hear them when I play back a sequence. I know everything else is correct because non modulation DSP effects work fine. It says something about turning the voice "on" in the sequence data but what does that mean? Program Change? Volume Control? The MIDI to SEQ converter only handles like 10 events so I'm confused on what I have to put in the MIDI in order to get the effect working. Has anyone tried using these effects before with success?
 

XL2

Established Member
Hi! I was messing around with the SCSP DSP to see what you could do with it and I got stumped reading this:View attachment 5490
I used the modulation voices it says to include but I can't hear them when I play back a sequence. I know everything else is correct because non modulation DSP effects work fine. It says something about turning the voice "on" in the sequence data but what does that mean? Program Change? Volume Control? The MIDI to SEQ converter only handles like 10 events so I'm confused on what I have to put in the MIDI in order to get the effect working. Has anyone tried using these effects before with success?
I had the exact same problem as you did.
I wanted to use reverb while underwater in my game via direct midi commands.
I spent a few hours trying to figure out how to make it work, but sadly the examples provided by Sega are really limited and poor, so I never got it to work.
I just ended up lowering the volume while underwater...
 
The thing is that I got the regular DSP effects like reverb/delay to work along with sequences. Here's a sequence I made being played back on the Saturn where you can clearly hear the DSP's reverb/delay. It's the specific effects the DSP labels as "modulation type" effects that I don't know how to use and yes, it took a while for me to get the DSP working because Sega's documentation/examples are nearly non existent.
 

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XL2

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The thing is that I got the regular DSP effects like reverb/delay to work along with sequences. Here's a sequence I made being played back on the Saturn where you can clearly hear the DSP's reverb/delay. It's the specific effects the DSP labels as "modulation type" effects that I don't know how to use and yes, it took a while for me to get the DSP working because Sega's documentation/examples are nearly non existent.
How do you fire an effect using midi commands? I only use the scsp with direct commands, but I couldn't figure out what to do to turn on an effect for one sound sample.
 
Well assuming you've set the correct parameters in your Tone Bank and your DSP program, all you have to do is set the DSP Effect and your mixer. In SGL this is slSndEffect() and slSndMixChange(). I assume you only have one bank and one DSP program so set your DSP Effect to 0 and your Mixer to mixer 0 of the first tone bank (0). Also it might be faulty emulation, but I could barely hear the reverb effect. I had to use the surround one to hear anything.
 
Take this with a grain of salt because I'm speaking from experience in music production rather than having gotten this to work on the Saturn hardware (yet!). But if you're not familiar, a send/return channel essentially sends some percentage of an audio signal to your effects device (in this case the Saturn Sound DSP) and returns the effect-transformed audio back (hence the send/return terminology) and either mixes it in with the "dry" (original, unaffected) sound signal, or the effect-transformed audio is routed to another separate sound channel where you can mix that output back into your overall mix at the volume you choose. I know the Saturn has "mixers" as part of the default sound driver system, but I'm still digesting how it all relates.

I hope that makes sense - That's how you'd use send/return effects on a physical analog mixing console, or on music software such as Ableton.

If the Sat's sound DSP is anything like the DSP effects built in to both my mixer and some of my synths, the effects all share the same input and output the combined sound together. I'll follow up on this thread when I have definitive answers (and hopefully sample code), rather than making assumptions.

I've been also looking into how hard it would be to make some simple GUI tools to replace the old 68k Mac tools provided by Sega for this stuff. Designing and composing audio and sequences would be vastly easier with a more visually-logical and modern interface.
 
How do you fire an effect using midi commands? I only use the scsp with direct commands, but I couldn't figure out what to do to turn on an effect for one sound sample.
Can't speak for the Saturn yet, but synthesizers (or other MIDI-compliant music hardware) take CC (Control Change) messages. For example, if I have a synth with built in send/return reverb and delay, I can look up the MIDI CC command numbers for various parameters (like how much of the dry sound I want to send to the reverb, or how long I want the reverb decay time to be), and change them at-will with a sequencer, PC music software, or even with bit-banged hex commands from an Arduino.

So you want to make sure you're sending signal to the effect, and mixing it back into the output.
 
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