Squinktronix Arpeggiator discussion thread

k-chaffin · November 11, 2023, 12:47am

Good news! Thanks.

Squinky · November 12, 2023, 12:50am

btw, I’ve never before ran into a module that changed the number of outputs on the fly like that. Is that a common thing?

k-chaffin · November 12, 2023, 1:55am

It is not common. Meander does it in order to be able to play triads, 7th and 4 voice chords. It sometimes causes problems as some (many?) modules have no provisions for it’s input cables to change polyphony on the fly. FM-OP seems to handle it okay, which is one reason I use FM-OP as my default voice module.

Squinky · November 12, 2023, 1:59am

well, I’m going to make Arpeggiator work with it

Squinky · November 12, 2023, 2:02am

Why not just leave polyphony in 4 voices all the time, and not use all of them when you don’t need to? Seems like that would have less compatibility issues?

k-chaffin · November 12, 2023, 2:04am

Thanks. An arpeggiator really needs to have dynamic polyphony as do probably quite a few other module types. I just now verified that FM-OP handles the Meander 3 and 4 voice chords fine with dynamic changes.

k-chaffin · November 12, 2023, 2:09am

The problem with leaving 4 channel polyphony all the time is that if an unused channel has 0V on it, a C4 will play. I’ve seen that many, many times. Meander actually changes the output port and thus cables polyphony as needed. As does Aaron Static ChordCV et.al.

Squinky · November 12, 2023, 2:23am

Ah,I guess assuming a mono gate, yes?

k-chaffin · November 12, 2023, 2:30am

For Meander, yes.

LarsBjerregaard · November 12, 2023, 5:09pm

Had a play with the Arpeggiator today. I like it.

Squinky · November 13, 2023, 6:18am

Wrote up a unit test to test that case, and sure enough, there’s the bug!

github.com

squinkylabs/SqHarmony/blob/adeef5403744c8b7cb46067e7b7bdbc9fbb4e029/tests/testArpegComposite.cpp#L647


      
              assertGT(arp->outputs[Comp::GATE_OUTPUT].getVoltage(0), 5);

          

              // now pull the gates. should turn off.

              arp->inputs[Comp::GATE_INPUT].channels = 0;

              arp->process(args);

              assertLT(arp->outputs[Comp::GATE_OUTPUT].getVoltage(0), 5);

          

              assert(false);

          }

          

          static void testMonoGateSub(bool changeVoices) {

              auto arp = make();

              auto args = TestComposite::ProcessArgs();

          

              // set up a mono gate, but poly cv input

              arp->inputs[Comp::CV_INPUT].channels = 4;

              arp->inputs[Comp::CV2_INPUT].channels = 4;

              arp->inputs[Comp::GATE_INPUT].channels = 1;

              arp->inputs[Comp::CLOCK_INPUT].channels = 1;

          

              // poly pitch

k-chaffin · November 13, 2023, 1:20pm

I was imagining you writing a unit test for this Sounds good.

Squinky · November 13, 2023, 6:03pm

yes, although in fixing it I realized it was a little trickier than I thought. All good, but I’m going get rid of the unit test I wrote yesterday, and write three new ones for all the weird cases in there.

k-chaffin · November 13, 2023, 8:46pm

How many channels are you going to allow? I ask because I am giving some thought to allowing more types of chords in Meander than just maj, min, dim and 7th. Meander internally understands 18 types of chords with some having up to 7 notes.

Squinky · November 14, 2023, 2:07am

I think it’s fully polyphonic, so 16 channels. I think internally it is limited to 32 notes, which gets used by those up/down patterns?

Jens.Peter.Nielsen · December 2, 2023, 2:45am

Loving the Arppegiator.

I’m missing a gate lenght knob+input - relative to the metric.

following the Arppeggiator with a gate lenght modifier is an option - but then you need assign too i guess to rotate poly aoutput channel, in case of overlapping gates… Perhaps it’s better taken care of in the Arpeggiator module.

Squinky · December 2, 2023, 4:42am

The manual says that the output gate length is the same as the input gate length. Is that not true, or is it not the best option?

Jens.Peter.Nielsen · December 2, 2023, 5:29am

I missed that - that should do it. Thanks.

Edit: yes, GATE output matches the CLK gate duration.

Squinky · December 2, 2023, 5:51am

oh, sry, I mis-spoke. I believe the output gate length is supposed to be the length of the input clock.