The Little Phatty does not correctly track MIDI Pitch Bend, as the analog bend circuit is out of tune in the middle of the
range. This has been confirmed to me by Amos, he’s still promising a fix ‘some day’
Can anyone confirm/deny - does the Slim Phatty bend pitch in tune?
It’s a real easy test to do - You can compare the bend to the guitar sound from a MIDI guitar, or
just do unison bends with another synth.
Set the pitch bend range on both units to a P5 or so, put the bend wheel in the middle and
listen - are both synths in tune? Set the bend range on both to a full octave, - still in tune?
With a pitch bend range at a perfect fifth or so, you will be about 1/8 to 1/4 tone out of tune in the
middle of the range - makes quite a warble when sounding in unison with another more in-tune
instrument.
If the SP does bend in tune - please let me know, I’ll probably dump the LP and get an SP since i doubt Moog is
gonna fix this. (it’s been a long time, and apparently I’m the only fool who cares about it)
Again, to repeat, this is about the LP/SP tracking MIDI pitch bend, not about bending with the LP wheel.
(altho if somebody has both an LP and SP, i’d be curious, do they track pitch bend together?)
Both the LP and SP bend is in tune it is just not linear, but this makes using the wheel more natural. Close to center it is easier to attain more precise control compared to when the wheel is out past half way. With a given pitchbend range set, you could use a tuner and check what midi CC out values correspond to a given amount of bend. The wheel sends midi messages linearly, so even though you would like to seperate the issues they are tied together. I don’t think its a bug, but by design with the player in mind. It would be nice if you could upload different response curves (for velocity too). With the ability to upload tuning tables it seems possible to have bend and velocity curves. Not sure if there is room for such improvements.
It sure is a bug - if you are using a guitar controller, or using a MIDI keyboard and layering
multiple synth sounds…because the LP goes quite out of tune in the middle of a bend!
It’s a really, really simple test. Before you blovate any more about ‘linear curves’,
try this, please.
- Take a MIDI keyboard, NOT the LP keyboard
- Slave the LP/SP to it.
- Slave a second synth, such as a DSI Prophet.
- Set the pitch bend on both to a perfect 5th
- Send the audio output of both to a mixer. Turn the levels up.
- Play a note
- Using the remote MIDI keyboard, bend the pitch a minor third.
Does the result sound musical and useful ??
Does it sound _in _tune??
SHF doesn’t for me. YMMV
And, btw, I’ve compared the LP to numerous synths, both
digital and analog, plus a Kenton MIDI/CV.
As I said previously, Moog admits the problem, but nobody apparently cares.
If I read your response correctly, the SP works the same as the LP. Oh well.
I am not certain on the SP. But if they are to track correctly in a poly chain I would think they need to track the same. It appears so in the poly chain demos.
Thanks for the new vocab word, I had to look up blovate. I didn’t mean to come across as a dick. Sorry.
If I recall correctly, the response goes back to the circuit that was used in the mini pitchbend controller. They wanted the voyager to have the same response and kept it the same with the LP.
If it is a must have, I think the midisolutions event processor could rescale the pitchbend in or out of the phatty to be in tune with your other gear. Definitely check with them before buying as I am not certain. They also may be able to program their velocity converter to convert pitchbend instead.
Also, if you used another synth as your controller with the kenton to send the phatty pitchbend via CV it should track. But you’d still have to filter out the pitchbend message from getting to the phatty if you still want midi control over notes and other messages. Both the midisolutions event processor and router are capable of midi filtering.
Yup, if I drive it with pure CV using the Kenton, all is good - the Kenton has good
scaling control. But, as you say, it would be nicer to use MIDI.
Moog told me the issue is due to the re-use of the original circuit from old Moog days,
apparently it was always non-linear, but pre-MIDI it wasn’t a big deal.
Thanks for the most polite reply.