ytsestef Posted July 26, 2012 Report Share Posted July 26, 2012 Is it possible to use an AOUT_LC module in 8/8bit mode to control two filters's frequency? (as opposed to 12/4bit for a single filter - ch1 frequency, ch2 resonance). Can it be done via the menus or do I need to change the firmware and recompile? If so, how do I proceed to do that? And would only 8 bits sound that bad? :P Quote Link to comment Share on other sites More sharing options...
ilmenator Posted July 26, 2012 Report Share Posted July 26, 2012 And would only 8 bits sound that bad? :P 8 bits give you 256 different values - expect some zipper noise when stepping through these. Definitely not recommended for dynamic filtering. If this is technically feasible I don't know. Quote Link to comment Share on other sites More sharing options...
ytsestef Posted July 27, 2012 Author Report Share Posted July 27, 2012 (edited) Well, I edited the following in setup.asm : #define AOUT_INTERFACE_TYPE 1 #define AOUT_LC_RESOLUTION_OPTION_M1 1 #define DEFAULT_F2A_CUTOFF_L_AOUT 1 #define DEFAULT_F2A_RESONANCE_L_AOUT 3 #define DEFAULT_F2A_CUTOFF_R_AOUT 2 #define DEFAULT_F2A_RESONANCE_R_AOUT 4 I hope it works (will have to wait for second filter board to arrive) If 8 bits per channel don't satisfy me, I'm, going to build a second AOUT_LC and stack them up sandwich-style (no more room inside the enclosure) Edited July 27, 2012 by ytsestef Quote Link to comment Share on other sites More sharing options...
Imp Posted July 27, 2012 Report Share Posted July 27, 2012 You could also use one Aout_LC to control cutoff/resonance of two filters in parallel. I found this to be enough for a stereo-setup. You can't do special sweeps with different values for the left and right Filter that way, of course. Quote Link to comment Share on other sites More sharing options...
ytsestef Posted July 27, 2012 Author Report Share Posted July 27, 2012 (edited) You could also use one Aout_LC to control cutoff/resonance of two filters in parallel. I found this to be enough for a stereo-setup. You can't do special sweeps with different values for the left and right Filter that way, of course. :o I haven't thought about that! Duh, scumbug brain got BSOD. :P Of course! Thank you very much. Daisy chaining the CV outs of the AOUT_LC doesn't increase the load? Isn't there any side-effect? As for the special sweeps, I guess I can make each channel sound somewhat different by adjusting static frequency and resonance pots on each channel, thus introducing a sort of "offset", right? Edited July 27, 2012 by ytsestef Quote Link to comment Share on other sites More sharing options...
Imp Posted July 27, 2012 Report Share Posted July 27, 2012 You don't even need extra pots to get some offset, since you can calibrate the filters a little differently. It's rather hard not to get any offset :rolleyes: but it sounds nice anyway. The increased load doesn't matter, it works like a charm in my setup. Quote Link to comment Share on other sites More sharing options...
ytsestef Posted August 31, 2012 Author Report Share Posted August 31, 2012 I found a problem with your implementation, imp (or I don't know how to do it properly :P ) I created a patch using the ML engine for 6-voice polyphony, then made the envelope control the cutoff frequency. The thing is, for the first 3 voices (left channel) the filter follows the envelope normally, but when it's time for the right channel to play, the envelope fails to trigger the filter. I guess the firmware assumes that 4 AOUT_LC are connected and the right channel CV is routed to the second AOUT_LC which doesn't exist. I have to mention that I have edited the .asm file as follows: #define DEFAULT_F2A_CUTOFF_L_AOUT 1 #define DEFAULT_F2A_RESONANCE_L_AOUT 2 #define DEFAULT_F2A_CUTOFF_R_AOUT 1 #define DEFAULT_F2A_RESONANCE_R_AOUT 2 ...in order to try to force the firmware to send both CVs through the same channel, but it didn't work, so, I guess each CV output is exclusive to one AOUT_LC only. Can you check if you can recreate the problem? I'm sure this can be rectified by modifying the firmware code, but I'm pretty much a noob at programming. It's a pity because I can't use the filter properly in ML engine, half notes are being modulated and half are static. Quote Link to comment Share on other sites More sharing options...
Imp Posted August 31, 2012 Report Share Posted August 31, 2012 You can set the patch to mono in the ensemble menu. This limits the voices to 3 (but in stereo now) and you still got only one envelope, but it will trigger on every note played. Sounds nice, to hold a chord and retrigger the envelope with one of the keys :cool: Quote Link to comment Share on other sites More sharing options...
ytsestef Posted August 31, 2012 Author Report Share Posted August 31, 2012 Damn, I needed 6 voices so badly! Another workaround would be via wavetables, but they behave strangely when they reset before the envelope ends (ie when you play fast) Anyone has any idea how hard it can be to alter the firmware to route both filter channels in one aout channel? Quote Link to comment Share on other sites More sharing options...
Imp Posted August 31, 2012 Report Share Posted August 31, 2012 I think it's easier to build another Aout. Quote Link to comment Share on other sites More sharing options...
ytsestef Posted August 31, 2012 Author Report Share Posted August 31, 2012 Unfortunately there's no room left in my build :( Oh well ... Thanks for your time anyway :) Quote Link to comment Share on other sites More sharing options...
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