I am experiencing the problem that Pianophonic CV-selected chord transitions are not reliable. There is already a thread on this in the Poly Cinematic category. This is occurring with the Keystep Pro both when triggering chords from the keyboard and the Keystep Pro sequencer as well as with my Orthogonal ER-101 sequencer.
My scope shows the delay between the gate achieving its peak value and the chord select CV achieving its peak value is about 20 microseconds for the ER-101. I believe for all intents and purposes, this should be insignificant.
I put a Doepfer A-162 trigger delay on the gate between the sequencer and the Pianophonic. I had to delay the gate by at least 3 milliseconds in order to achieve reliable chord transitions.
This is not a problem of the sequencer or keyboard delaying transmission of the chord select CV or the CV still changing when the gate goes high. If that were the case, a trigger delay only slightly exceeding 20 microseconds would have been required to address the issue. The problem appears to be that the Pianophonic takes about 3 milliseconds to register the fact that the CV has changed, and this is AFTER the Pianophonic has responded to the gate and started playing the chord.
I'm not an embedded systems guy, so I don't know how difficult this might be to address, but this is supposed to be a Eurorack module, and the most basic function for any sound module, i.e., playing a selected sound, is non-functional on the Pianophonic without incorporating an additional module or somehow delivering the CV well in advance of its associated gate. If this isn't going to be addressed in a firmware update, then I suggest it should be mentioned in the manual that a 3 millisecond delay on the gate signal or setting the CV in advance of its gate is required to make the module function reliably. That inclusion would have saved me several hours of wasted time.
This issue has now been addressed and is available to download in the latest firmware release.