creatorlars Posted December 26, 2007 Report Share Posted December 26, 2007 Well Christmas vacation is nearing an end, and I have my +/-12v power supply, all buttons/LEDs, the LCDs, and the 6 MIDI ports (via 4 IICs) functioning without a hitch!!! Wiring has been a troubleshooting nightmare and next time I'll definitely want to try to make a PCB for all of the panel components -- or at least mount everything on a single veroboard. Now I'm just rearranging things to make sure everything is mounted snugly & securely when the frontpanel is finally mounted in the enclosure.Only thing left is the AOUTs. I've got 8x quarter inch jacks for CV Gates and 8x quarter inch jacks for CV Outs. I've got the gates going from the core, and I just wired in my AOUT module. Before I begin testing and adjusting those trimpots, I was wondering if anyone had tips for how to calibrate the AOUT gates & CVs without the MBCV application, assuming no access to analog modules? I'm guessing I just need to make sure I've got fresh batteries in my multi-meter and test the voltage.... Should I be calibrating the CVs to make sure I'm getting exactly 1v/octave from 0v to 10v? Or is it -5v to 5v? What MIDI octaves are standardly used for which voltages? I have to admit my ignorance in this area. Should I try to use some sort of software oscilloscope as well? I'm mainly using these to control velocity/accent of analog drum modules, but also will be controlling VCO's that need to be pitch-accurate. I could always save calibration for later, but this box is going to be a bitch to get back apart for that, and I'd like to avoid it if possible. Any tips on how you've done calibration before? Quote Link to comment Share on other sites More sharing options...
creatorlars Posted December 27, 2007 Author Report Share Posted December 27, 2007 Well I got things working after some board troubleshooting. Judging from what I'm getting, I'm making a guess that the CV outs need to be tuned so that the middle C is 5v, and the voltage scales at 1v/octave up and down from that? Quote Link to comment Share on other sites More sharing options...
TK. Posted December 28, 2007 Report Share Posted December 28, 2007 Hi,no, the voltage range is calibrated on a different way: c-1 outputs 1V, C-0 2V, C-1 3V, C-2 4V, C-3 5V, etc...So, just play a sequence with C-0 notes, turn the trimpot until 2V will be output, thereafter play C-3, check that the voltage is 5V, play C-0 again, check that the voltage is still 2V... iterate until you are satisfied with the result :)Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
wicked1 Posted March 6, 2008 Report Share Posted March 6, 2008 Usually when tuning things like this there are two adjustments. The voltage and the span. If you set c0 to 2v, then adjust the span so that c3 is 5 volts, c0 would then most likely be lower than 2v. (well.. or more depending on which way you adjust the span)Does the software take care of some of that? I must admit, I haven't quite finished the module, so maybe it will make more sense when I get my hands on it. Quote Link to comment Share on other sites More sharing options...
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