Keyboard CV generation problems? (with video)
2012-05-16 by Paul
Hello everyone. Any insight from M/P wizards here would be much appreciated.
There's a video I made of the problems: http://youtu.be/MAD3U8O3jA0
Symptom: Playing M/P's keyboard produces wrong pitches. It's scaled tighter (microtonally), with occasional skips. In "normal" transposition the top octave of keys [32-44], span about a P5th in pitch. Then between the B3 and C4 [31 and 32] there's another 5th. Then we cover a major third in the span of an octave and a minor third [key B3; 31 to Ab2; 17]. The interval between Ab and G is a major 2nd roughly. Then there's a minor third heard divided between the last remaining 14 keys [16 to 1]. The pitches waver audibly. Using the octave transposition moves the irregularities faithfully - ie the skips.
External CV control is fine, everything sounds good.
This problem got worse gradually, but over the course of a month or two, and after a long period of working correctly.
From what I've read, it sounds like it could be the power supply voltages, or the key assigner. It doesn't seem like a problem with the matrix in the keybed because the symptoms don't align with how it's divided up. Thank you for any help.
other keywords:
tuning, calibration, tune
There's a video I made of the problems: http://youtu.be/MAD3U8O3jA0
Symptom: Playing M/P's keyboard produces wrong pitches. It's scaled tighter (microtonally), with occasional skips. In "normal" transposition the top octave of keys [32-44], span about a P5th in pitch. Then between the B3 and C4 [31 and 32] there's another 5th. Then we cover a major third in the span of an octave and a minor third [key B3; 31 to Ab2; 17]. The interval between Ab and G is a major 2nd roughly. Then there's a minor third heard divided between the last remaining 14 keys [16 to 1]. The pitches waver audibly. Using the octave transposition moves the irregularities faithfully - ie the skips.
External CV control is fine, everything sounds good.
This problem got worse gradually, but over the course of a month or two, and after a long period of working correctly.
From what I've read, it sounds like it could be the power supply voltages, or the key assigner. It doesn't seem like a problem with the matrix in the keybed because the symptoms don't align with how it's divided up. Thank you for any help.
other keywords:
tuning, calibration, tune