SH-101 pwm

[andy_FX]

http://xhip.cjb.net/temp/public/on_off.mp3

ok, so you dont get the effect as audible when the output is taken off the vca because the vca cuts off almost immediately when the voltage starts to droop.

http://xhip.cjb.net/temp/public/osc_stuff.mp3

i guess mp3 kind of sucks, so if somebody wanted to look closely at that:
http://xhip.cjb.net/temp/public/osc_stuff.wav <-- dont download this if you only want to listen[/b]

This sounds great. It osc_stuff.mp3 a sample of an analog synth? You get more interesting sounds when you start playing as you switch on a synth

[mystran]

I think it's easier if you use blamps instead of bleps and have each ramp time fixed which is your slew rate limiting. You can have a different slope on the up and down easily this way. So you never jump with a step, you always ramp to the new value at a constant rate.

If you only have one or two possible rates, I think it's waste of CPU to build ramps, since you can just integrate those into your BLEPs; say convolve ramped steps instead of the trivial step when building the BLEPs.

Ofcourse if you want to modulate the ramps then BLAMPs would make sense; say, we're assuming limited gain will cause ramps longer than slew-rate would imply, and want to simulate lower-frequency saws causing longer ramps in the comparator output, or whatever. I guess that could be a good thing to do if one wanted some even harmonics in the high-register, because then that effect would be reduced for higher fundamental frequencies.

Have to see if I can be bothered to try that tomorrow. Shouldn't be much work and I'd need some other similar waveshapes in my oscillator core anyway, but to be honestly I probably should leave my oscillators (and filter) alone and work on finishing more relevant stuff.

[andy_FX]

It's easier to center your corrective grain if you keep them as simply C0, C1 ... CN corrections.

[nollock]

you shouldn't be touching the pulse-width at all.. what i've described already does this effect without needing to meddle with any additional stuff like pulse width.

I thought I was doing what you described.

Tbh i find your explanations hard to follow sometimes. Probably because alot of what you say is grounded (no pun intended) in electronics terminology which is largely unfamiliar to me.

For example I thought the reset point was the point where the acumulator wraps back to zero, by point i mean the point in time. But it seems now it you mean the actual voltage level at which the phase resets.

Which tbh doesnt seem that different to just having a random offset on the phase accumulator. By that I mean on reset generate a random offset and use that as an phase accumulator offset for the whole next cycle. Ie...

if (phase > (1+offset))
if ((phase-offset) > 1)

are indentical as far as a positioning the reset are concerned.

[aciddose]

they are, i was thinking you were adding to the accumulator as in, per-sample. once again using slightly different terminology there


"This sounds great. It osc_stuff.mp3 a sample of an analog synth? You get more interesting sounds when you start playing as you switch on a synth"

it is analog, the oscillator core is a discrete SCR much like the cores in the tb-303 and ms-20. i use mega-bypassing here though which makes it a heck of a lot cleaner than those two. i should give it a go on a oscillator board where the reference isnt bypassed. i'm also using a discrete comparator here, i believe the RC4558 is used in the ms-20 while a naive single pnp transistor feeding from a 'battery' capacitor is used in the tb-303.

so, they're quite unique (all three of them) but the general timbre should be the same in terms of what we've been discussing here.