Minimoog OS and MCV4 CV/GATE Midi ! solved problem

[Olivier1975]

Hello everybody,

I have a problem and I do not find a solution on Internet !!!

I connected my Minimoog Oldschool with a Doepfer MCV4 towards Atari ST Computer (or Apple towards M-Audio Midi...).

I wish that my Midi connection play the notes on Minimmog without I not posing the fingers on the keyboard.

The liasion Midi is carried out (red diode ok).

But I am obliged to leave a finger on the keyboard to hear the played sequence.

It can be transposed if I change note. But it is not what I wish. I want just to intervene on Minimoog to change the parameter of the sound (LFO, Filters…). I want just that my keyboard behaves like a expander.

Can you help me to solve this problem.

I have Mono cables, not stereo... (problem ???).

Here my branch:

MCV4 Gate -> Minimoog KB Gate.
MCV4 CV1/2 -> Minimoog Pitch.
MCV4 Midi In <-> Atari Midi Out.

Thank you very much for your assistance.

[acorkos]

* ENVELOPE GATE SWITCH selects whether the envelopes will be triggered by the keyboard, on , or by an externally-applied gate.

it's the red switch at the bottom right of the control panel...make sure you have it set to EXT

[Olivier1975]

I do not understand "set to Ext" ???

There is only one diode on the MCV4, it is a switch to establish the connection midi.

[Olivier1975]

Ah ok, I see !

I thus connected a main keyboard on Minimoog and I can play via this one. But while putting on “ext.”, the sound is infinite… with sustain....

how thus, to play note by note without this???

[Amos]

set gate switch on Voyager to "Ext" and connect MCV4 Gate output to Voyager Gate input. When MCV4 sends note on/off Gate signal, Voyager should follow correctly. Does it?

[Olivier1975]

A person of this forum gave me the solution, I also give it to you:

MCV4 Gate / S-Trig ----> Env Gate (blue)
MCV4 CV1/2 -----> pitch

Env.Gate ---> On / External

And it's Ok, we can control via midi Minimoog OS ... with Master Keyboard or, for me an old Atari 520 ST.

[simontonka]

Hello, I just found this in a sound on sound review of the voyager old school. I am very near to purchase and am slightly concerned about the midi/cv control. Will I be able to control a MMVOS with my kenton pro solo? I believe it is much the same as a doepfer mcv4.
Thanks for any help on this. Its a lot of money to part with if I cant get the tight sequenced basses I want!
The link to the review is here.

http://www.soundonsound.com/sos/dec08/a ... school.htm

This is the part of review which concerned me!!

"Despite the Old School's diverse connectivity, a few desirable features failed to earn a place amongst the throng. There's a dearth of voltage outputs, although, as an optional extra, these can be added courtesy of Moog's VX351 CV Expander. This hooks up via a small multi-pin connector and provides access to voltages produced by the keyboard's velocity and aftertouch, as well as the mod wheel, and more. Be aware that this expander was created for the original Voyager, so some of its outputs (for example, that of the Touch Surface) don't apply to the Old School or, in the case of the keyboard pitch and gate outputs, duplicate what is there already.
It's fortunate that CV and Gate interfacing are on board, since, with MIDI cast aside, the Old School needs some way to interact with the outside world. In my own tests I found that the keyboard's output voltage was scaled much lower than that of my Roland SH101. Oddly, all notes below the keyboard's bottom C sent the Roland into a spin — although three octaves (C-C) worked reliably. Investigation revealed that the Old School puts out negative voltages for any notes below the lowest C, which some synths (such as the 101) can't cope with.
Unfortunately, it was the incoming pitch-CV response that caused me real problems. Driven by the SH101 or by my Kenton Pro 2000 MIDI-to-CV converter, the Old School did not track accurately at all. Moog inform me they decided to omit CV input calibration from the design, and I am advised that the best solution is to use an attenuator from either a VX351 or a Moogerfooger CP251 Control Processor (or a similar module, if you have a modular synth) to tweak the incoming voltage until the Old School plays in tune.
Personally, I can live without patch memories and MIDI control of knobs — but without basic MIDI note reception, I can't drive those chuggy Moog basses from a sequencer without added cost or complication. At this point my nostalgia transferred briefly to the dawn of MIDI: the solution to exactly this kind of voltage incompatibility."

[SteveD]

Hi -

There are a couple shortcomings in that review - look what feature the Kenton 2000 pro solo has to deal with tuning:

(From the Kenton manual)
"CV x Scale ( -127 to +127 default 0)
- This is used to tune in the octave scaling of your analogue synth. Will only need adjusting if your
synth sounds out of tune as you play further up the keyboard (see `Tuning in Your Analogue Synth`). -
Check whether CV select has been set correctly (see below). "

The Voyager OS's VCOs are pretty darn linear, so if the scaling isn't right, it should be really easy to adjust on the Kenton!

As far as the Roland SH-101 - notes below C are below zero volts from the voyager and the roland SH101 takes ONLY 0 to +5 (remember it can be a battery operated synth, so it probably can't operate belopw 0V).

So the issues brought up by the reviewer in this case could have been understood with a small amount of extra thinking through the problem. He is right that using analog CVs beteween different manufacturer's products takes a little more thought sometimes - but once you have it set up - you should be good to go!

Hopefully that helps as far as understanding this issue better.
Cheers!
SD