Minimoog for the poor ...

proximo · Post by **proximo** » Sat Jun 26, 2004 7:35 am

Minimax is awesome .. but I think hardware still is ahead.
There is no way I want to spend 3000€ for a Voyager nor 2000€ euro for a old Mini which might not be working right (and no midi).

For a little while I was comtemplating this Moogerfooger MF-101, but I thought, what is a point to have a real Moog filter without envelope and mods ... this env follower won't do the trick, it is more for guitar players.

Then I saw all those CV entries on the Mooger, specially one for the filter.
Then I thought what could output an ADSR with CV ? ... the Waldorf Pulse+ !

It really works great, and it sounds so hot ! (for 600€ both second hand).
The Pulse+ can actually output 15 different parameters to CV (LFO, Env, Velo etc etc), and each param can have a specific amout.
Here are 3 examples with ADSR (creamware Chorus and delay were used) :
1) http://perso.wanadoo.fr/mks-80/moog.mp3

2) http://perso.wanadoo.fr/mks-80/moog_rezo.mp3

3) http://perso.wanadoo.fr/mks-80/moog3_self_oscill.mp3

I am a happy camper !
Cheers,
Proximo

darkrezin · Post by **darkrezin** » Sat Jun 26, 2004 11:58 am

Actually you don't even need a Pulse.. you can output CV from Pulsar Modular - just connect any control source (you can shape and smooth and generally fuck with it in any way using any processor) to an audio out, and connect this to the CV input of your analog equipment.

wayne · Post by **wayne** » Sat Jun 26, 2004 8:25 pm

On 2004-06-26 12:58, dArKr3zIn wrote:
you can output CV from Pulsar Modular

darkrezin · Post by **darkrezin** » Sun Jun 27, 2004 7:33 am

I should also add that if you use a ValMonitor module (part of Flexor, and was also released as a freebie - look in the Devices section), assign a controller to the fader, and connect the output to an audio output, you have an instant MIDI to CV converter

astroman · Post by **astroman** » Sun Jun 27, 2004 8:30 am

any module you connect to the Modular's anolog out which is further connected to the cards physical analog outs will produce a voltage change there.
Just measured a bipolar value fader produces from -1,68 to +1,92 volt on the outs

Seems some adjustment for zero point is required, but that's an easy trick - and it seems limited to that range, no amplification possible beyond that point.

Great tip, Dark - but it's not mentioned in the manual, is it ?

cheers, Tom

darkrezin · Post by **darkrezin** » Sun Jun 27, 2004 8:49 am

Not sure if it's in the manual, I just found out one day when messing about with my analog filter with CV in. Needless to say I was blown away when I figured it out

alfonso · Post by **alfonso** » Sun Jun 27, 2004 9:14 am

I don't have analog gear, but I find this topic very interesting...

Did anyone try to use MVC freq. out? If you shortcut gate out and e-sync input, it outputs when receives notes...could be it's scaling useful? otherwise you can add a pitch modifier....

...to have something more than a theremoid device...

proximo · Post by **proximo** » Sun Jun 27, 2004 12:34 pm

@dArKr3zIn

Mate, I need more info on how you achieved that ... sounds interesting indeed.

I have tried with a basic setup (with Modular III) : ie a VCA mod. by an ADSR.
I guess to output a current to an analog audio out you have to produce a sound..
In my case I took a basic waveform (with MODIII) mod by the ADSR.
First the voltage did not seem powerful enough, so I amplified it.
I hear the effect of the ADSR on the moog filter (though not right, voltage issue ?)
but the output waveform used to produce a current also produces a modulation on the filter and end up having a X-Mod effect like FM (with the sound entering the input of the moog filter) and it does not sound right (interesting though).
Cheers.
Proximo.

[ This Message was edited by: proximo on 2004-06-27 14:00 ]

astroman · Post by **astroman** » Sun Jun 27, 2004 1:11 pm

proximo, you can connect the adsr output directly to (a free) one of the modular's audio outs, which then goes to scope analog out and externally to an amp (to adjust the voltage) for your module

cheers, tom
ps I could just watch the envelope decaying on the voltmeter...

[ This Message was edited by: astroman on 2004-06-27 14:13 ]

Michu · Post by **Michu** » Sun Jun 27, 2004 2:34 pm

Proximo, like astroman said
you need to generate CV in modular, ie connect envelope out to audio out in shell.
also you need additional pair of analog outs to route it to gear, ie some converters attached to digital connector or additional card with analog i/os on it.
AFAIK, DarkResin has got 2 Pulsar cards and uses one for monitoring and other for CV outs, sorry if i messed this up DR

proximo · Post by **proximo** » Sun Jun 27, 2004 6:10 pm

Hi peeps,

Thanks for your help !
Ok, I had a Linear VCA module between my ADSR and the out of the MODIII which prevented it to work...
I now see the voltage coming out, but it is much too weak.
The Mooger accept from 0 to 5.7V.
The Pulse delivers from 0 to 5.4V (I measured).
And I measured the Pulsar out from 0 to 1.25V (at max sustain level).

I tried to amplify with my mixer but had crazy result : voltage was varying from + to - ... so it was not and ADSR anymore

I am suprised it worked well for others.

any idea on how I could properly amp that signal ?

Thanks again.
Cheers,
Proximo.

[ This Message was edited by: proximo on 2004-06-27 19:11 ]

astroman · Post by **astroman** » Sun Jun 27, 2004 6:37 pm

yeah, I overlooked this - afaik most audio amps are ac coupled which means that a slowly changing voltage level cannot be transmitted at all.
You need a 'technical' amp for this, like those used in measuring (with dc coupling). Your app isn't precision critical so a simple transistor stage will do, but right at this moment I'm not aware of anything commonly available to provide this feature.

It's simple to do-it-yourself and doesn't even need a circuit board, just powersupply (or a battery), a transistor, 2 or 3 resistors and the IO connectors.

cheers, Tom

[ This Message was edited by: astroman on 2004-06-27 19:46 ]

proximo · Post by **proximo** » Mon Jun 28, 2004 5:34 am

Thanks Tom !
It's just I wish I was able to do that .. but I know nothing about electronics

Cheers,
Proximo.

darkrezin · Post by **darkrezin** » Mon Jun 28, 2004 6:33 am

I use an Analog Systems FB3 filterbank which seems to react pretty well to the Pulsar's CV output.. I don't have the tech specs handy here unfortunately. It just worked for me first time so I didn't really worry about it.

astroman · Post by **astroman** » Tue Jun 29, 2004 5:21 am

On 2004-06-27 19:37, astroman wrote:
...
You need a 'technical' amp for this, like those used in measuring (with dc coupling). ...

after peeking at some ciruit schematics that's a bit of nonsens...
but since regular audio amps preferably limit the ultra-low frequency range for speaker safety the control signal doesn't pass though.

cheers, Tom

proximo · Post by **proximo** » Tue Jun 29, 2004 6:26 am

Thanks Tom,
I was looking at this :
http://www.kemo-electronic.de/en/module/m031/index.htm
But after your post, I guess it won't do the trick, right ? cause of the bandwidth ?
Shame ..

Cheers
Proximo

astroman · Post by **astroman** » Tue Jun 29, 2004 4:05 pm

indeed, that's completely unusable - might be even dangerous due to power rating of the amp.

Out of curiosity I tried some basic circuits and finally succeeded with something originally used to drive a VU meter on a receiver - I have no idea about the circuit design, but it seems safe imho, at least no smoking victims here

Code: Select all

  6V      in      out
 +  -    g  s    g  s
 |  |____|  |    |  |
 |       | 10k  10k 10k
 |       E  B    C  |
 |__________________|

I've used a BC547 transistor because it was the first crossing my way, any npn type should do.
As you can see on the schematic (hope the formatting works) it consists only of the transistor, 3 10k resistors, 2 IO plugs and a powersupply (or battery) plug. The EBC letters mean the respective pin on the transistor, emitter, base and collector.

Maybe someone with more insight can comment the circuit...

cheers, Tom

Post by **hubird** » Tue Jun 29, 2004 5:36 pm

it's exactly like the yet secret formation of the dutch team tomorrow in HOL---POR

proximo · Post by **proximo** » Wed Jun 30, 2004 11:41 am

Hehe, It will be a hot match tonight ! May the best win!

Hey thanks Tom ! that seems cool.
I will go to the eletronics shop to get those 4 components ... hoping I will not screw them up during soldering

..

Cheers,
Proximo

[ This Message was edited by: proximo on 2004-06-30 12:42 ]

astroman · Post by **astroman** » Wed Jun 30, 2004 5:03 pm

I hope you're more lucky than the Dutch team

in the circuitry above I could measure a voltage change roughly in the range of the supply voltage. I used an outdated battery with 8V and yielded changes somewhat below that level, so a 6V supply should end at 5.5V.
The outgoing ground is not connected to anything else and the circiut is somewhat depending on the receiving side.
The + supply in the diagram runs through the receiving device and obviously was closed only by the voltmeter's high resistance. Possibly you need to insert a 200k potentiometer bridging the out connector to adjust it.
For safety I would get a battery holder for 4 1.5V cells and try it out.

have fun, Tom