DIN midi to CV/micro USB question (Loopa/Plinky related)

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Philthy
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DIN midi to CV/micro USB question (Loopa/Plinky related)

Post by Philthy » Thu Apr 08, 2021 1:46 am

Hi Folks,

Bit of a noob question....

Over the last year or so I’ve build myself a nice desktop rig consisting of:

1. Midiphy Loopa on midi sequencing duties
2. Tsynh
3. Lil Erebus
4. LXR
5. Keystep possibly to be replaced by a Reface CP.

I would love to integrate a Plinky into this rig when Thonk does the next run of PCBs.

The Plinky has midi and power over micro USB plus the usual clock, gate, pitch and mod CV inputs.

I want to avoid using a laptop as my whole rig had been build around the fact that I do not want to stare at a screen.

Is there a way I can connect the DIN midi output port on the Loopa to the Plinky via its CV inputs? Ie assuming I use the Plinkys micro USB for power duties only.

Thanks

pjbulls
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Re: DIN midi to CV/micro USB question (Loopa/Plinky related)

Post by pjbulls » Thu Apr 08, 2021 3:41 am

If I understand correctly you want to convert the DIN MIDI from your Loopa into CV, which you then feed into the Plinky. This is certainly possible & many (DIY-able) options exist, such as MI Yarns, Befaco's MIDI Thing, and EricaSynths DIY MIDI-CV II (the latter you will have to make yourself entirely).

It would also be an option to convert the DIN MIDI into USB, and then feed that into the Plinky - from reading the docs it can accept but not output MIDI. Haven't seen this as a DIY solution yet (usually people want to go the other way around), but it is also definitely possible.

Philthy
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Re: DIN midi to CV/micro USB question (Loopa/Plinky related)

Post by Philthy » Thu Apr 08, 2021 7:31 pm

Thanks for the reply.

Re the DIN MIDI to CV convertors - the Plinky has eight voices. Is anyone aware of convertor, DIY or otherwise, that is polyphonic?

Re DIN MIDI to USB convertors - I was was aware of these but wasn't sure how would I power the Plinky? It has MIDI and power over micro USB.

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dubonaire
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Re: DIN midi to CV/micro USB question (Loopa/Plinky related)

Post by dubonaire » Thu Apr 08, 2021 8:24 pm

Philthy wrote:
Thu Apr 08, 2021 7:31 pm
Thanks for the reply.

Re the DIN MIDI to CV convertors - the Plinky has eight voices. Is anyone aware of convertor, DIY or otherwise, that is polyphonic?

Re DIN MIDI to USB convertors - I was was aware of these but wasn't sure how would I power the Plinky? It has MIDI and power over micro USB.
There are polyphonic DIN MIDI to CV converters eg Doepfer A-190-5 and Vermona qMI 2, but as far as I can tell Plinky only has 1 gate and 1 pitch input, so it does not have the functionality to receive polyphonic inputs.

Philthy
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Re: DIN midi to CV/micro USB question (Loopa/Plinky related)

Post by Philthy » Thu Apr 08, 2021 9:59 pm

dubonaire wrote:
Thu Apr 08, 2021 8:24 pm
There are polyphonic DIN MIDI to CV converters eg Doepfer A-190-5 and Vermona qMI 2, but as far as I can tell Plinky only has 1 gate and 1 pitch input, so it does not have the functionality to receive polyphonic inputs.
Thanks. Yes you are almost correct, the Plinky has single clock, gate and pitch CV ins and 4 mod CV ins. Could you explain to me how these function on an eight voice synth? If it limits the polyphony then it's probably a deal breaker regarding exploring a MIDI to CV solution.

Edit: I found this in the preliminary manual in the original Plinky thread:

Jack Inputs and Outputs
The 8 jack inputs, at left, from top to bottom provide:
 modulation (A, B, X, Y) with -5v to 5v range
 a pitch input for transposition via a V/oct input in -2v to 5v range (with quantization controlled by the u secondary parameter)
 an analogue gate that scales the openness of all low pass gates (0 -5v)
 a 1/16th note clock input
 an audio input that is mixed with the synth output as well as being sent to the FX units.

The 8 jack outputs, on the right, from top to bottom provide:
 1/16th note clock out (>5v), (so that plinky can clock other devices)
 Trigger (>5v pulse on every new note)
 pitch hi (1v/oct) of the rightmost note that is playing, respecting the arpeggiator, -1v to 5v
 analogue gate, being the maximum level of all 8 ADSR envelopes
 pitch lo (1v/oct) of the leftmost note that is playing, ignoring the arpeggiator. -1v to 5v -useful as it is usually the bass note
 analogue pressure, being the maximum of all finger pressures detected, ignoring any envelope
 stereo audio out. The lower (left) output can be used as a mono output when nothing is plugged into the right output

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dubonaire
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Re: DIN midi to CV/micro USB question (Loopa/Plinky related)

Post by dubonaire » Fri Apr 09, 2021 12:40 am

Philthy wrote:
Thu Apr 08, 2021 9:59 pm
dubonaire wrote:
Thu Apr 08, 2021 8:24 pm
There are polyphonic DIN MIDI to CV converters eg Doepfer A-190-5 and Vermona qMI 2, but as far as I can tell Plinky only has 1 gate and 1 pitch input, so it does not have the functionality to receive polyphonic inputs.
Thanks. Yes you are almost correct, the Plinky has single clock, gate and pitch CV ins and 4 mod CV ins. Could you explain to me how these function on an eight voice synth? If it limits the polyphony then it's probably a deal breaker regarding exploring a MIDI to CV solution.

Edit: I found this in the preliminary manual in the original Plinky thread:

Jack Inputs and Outputs
The 8 jack inputs, at left, from top to bottom provide:
 modulation (A, B, X, Y) with -5v to 5v range
 a pitch input for transposition via a V/oct input in -2v to 5v range (with quantization controlled by the u secondary parameter)
 an analogue gate that scales the openness of all low pass gates (0 -5v)
 a 1/16th note clock input
 an audio input that is mixed with the synth output as well as being sent to the FX units.

The 8 jack outputs, on the right, from top to bottom provide:
 1/16th note clock out (>5v), (so that plinky can clock other devices)
 Trigger (>5v pulse on every new note)
 pitch hi (1v/oct) of the rightmost note that is playing, respecting the arpeggiator, -1v to 5v
 analogue gate, being the maximum level of all 8 ADSR envelopes
 pitch lo (1v/oct) of the leftmost note that is playing, ignoring the arpeggiator. -1v to 5v -useful as it is usually the bass note
 analogue pressure, being the maximum of all finger pressures detected, ignoring any envelope
 stereo audio out. The lower (left) output can be used as a mono output when nothing is plugged into the right output
I was aware of the other CV ins but they are used as modulation sources.

Normally, modular polyphony is done by having multiple VCOs, VCAs, VCFs and envelopes. Doepfer, for example, has developed some modules specifically for (four note) modular polyphony. A quad VCO, quad VCF, quad VCADSR and an octal VCA. 8 VCAs because it's usual to use two VCAS in a conventional voice set up. The modules all take independent inputs.

If you were controlling those by midi, you would use one of the four voice midi to CV modules.

Plinky does not have individual inputs for each of the 8 voices. It only has one pitch input and one gate input and a few CV inputs. You change the voice behaviour with the front panel right? The module would be huge if it was designed with individual inputs for each voice. There are other modules that can produce chords etc that are designed the same way like Braids and Shapeshifter.

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