I took this six years old message to retrieve the old situation and compare if I'm doing right:
Nu Audio Science wrote:
OK I actually got a little bit done, Not enough so you can listen though
Some of the modules are in the wrong order for instance the VCA goes after the Filters in the signal chain.
The DCO ranger needs sorting and intergrating into the DCO Module.
Im not sure how to achieve the different shapes needed possibly waveshaping ?
I will post pics of the needed shapes from the Owners Manual of the J2 later.
The Envelope is temporary until we can create a 8 segment Time Level type of envelope .
EDIT* On second glance at the picture above i think the DCO needs an ENV mode aswell, I will check in the manual (Which i was lucky enough to find in the loft)
Well I go point for point:
-VCA stage on the circuit board is actually located between the LPF 6-voices filtering stage and the HPF/Chorus stage, because the HighPass processing is performed on the whole signal, not voice per voice, proof is the HPF is selectable via switch modes in a typical configuration on analog synthesizers, it came to my attention looking carefully at the original block diagram:
-I've done the proper DCO ranges sorting and all about that, and an additional check to the minimum/maximum rates will be performed in comparison with a real machine, after completing of the programmer and presets management scheme which is still under development...
-No need for waveshaping I think, I provided the fixed waves with the sampling/wavetabling work, just the PWM shapes are incorrect at the moment, being too exact, too DIGITAL and set very bad apart from the WT oscillation.
Needs fixing of course, I was thinking of adding a low sine or saw/something to the PWM shapes. If you have ideas here, please contribute.
-Well for "8 segments" I think NAS meant "8 values", being L-x and T-x doubled for each stage. Actually the original one is practically a 7 values/5 stages envelope.
I'm actually implementing a variation of the multistage SM envelope to be adapted for the purpose. I'm blocking the curves to resamble the original ones and setting times and amplitudes, another prototype is coming in days with better graphics and interface from v70 too.
See ya soon!
PS: add the provided font to your Windows Fonts folder if you want a realistic LCD display...
and thanks to AM for the display cells!