Problems with my rogue?

xtudis · Post by **xtudis** » Mon Jun 12, 2006 11:30 am

hi threr,

I just got a rogue at last!! i love the fat bass sounds you can get from her!!! I have one question for you. How many semitones changes the pitch wheel? And the Vco Oscillator?. Can i modify them? In mine it only changes a 7th but i´d like to get an octave. The same with the Mod VCO. Any help please?

Thanks.

Dr.T · Post by **Dr.T** » Tue Jun 13, 2006 2:19 am

Hello there x tudis,

Pitch wheels on the old Moog synths were never originally designed to cover a really huge frequency range - I don't remember getting an octave out of any of them. But since the circuits are relatively simple analog circuitry (much of it discrete elements), they can be modified.

I trust you already have downloaded the schematics of the Rogue; you can find them e.g. at: http://www.hylander.us/images/schematic ... Manual.pdf

You could probably extend the bend range by decreasing the value of resistor R25 (looking at the Rogue schematics, R25 can be found to the upper left of easily distinguishable noise waveform designated with "+5V" and "-7V" in the left part of the circuit diagram. This resistor controls the maximum bend range. I can't tell you which value you will need - you will have to experiment a bit. I would not make it too small (below 100 k).

A possible approach could be to replace R25 by a series connection of a 220 k resistor and and a 1 M trimpot (connected as a variable resistor) because this would give you an adjustable bend range. You could even install a regular control to set the bend range from the control panel.

I do not quite understand your other question - do you want more pitch modulation amount? If so, this could be achieved by making R27 somewhat smaller - again, it should not be too small (below 100k), and you will have to experiment.

Bear in mind that modifying your Rogue might devaluate it for a potential future buyer, and that if you have little experience with working on electronics, there is a certain risk that you accidentally damage your precious synth. That said, the old analog synths are easy to work on and a joy to modify. The results are most often very gratifying.

Kind regards,

T.

writeroxie · Post by **writeroxie** » Tue Jun 13, 2006 5:50 am

note: the source bends up and down a full octave

xtudis · Post by **xtudis** » Tue Jun 13, 2006 5:56 am

thanks, Dr. T. you really help me on that. I don´t mind to rectify the moog cause i don´t thing i´m gonna sell it anymore. I´m a musician-collector with no money jajaja, at the moment i got this moog and a Hammond to restore.

The other question was about the oscilator on the modulation part. When i connect the osc works as an arpegiator ( two notes the one you´re playing and another one that is about a 13th up) so i´d like to change it to an octave. I know I know I´m a pain in the ,,,,.

Thanks again.

Dr.T · Post by **Dr.T** » Tue Jun 13, 2006 8:06 am

@ writeroxie:
thanks for correcting me - since you have the Rogue there you are the one to judge this! I just don't remember any of the Moogs I owned in the past (Prodigy, Rogue, Multimoog) to have that kind of bend range ...... I apologise very much if I have disseminated incorrect info!

@ x tudis:
unfortunately, I still do not understand the question ..... what do you connect? Do you switch on the "Oscillator Modulation? If this results in "two notes" then you probably have selected the "square" modulation shape?
You say that you get about an interval of a 13th - if you need less why don't you just reduce the modulation amount with the wheel? In case you want to have exactly one octave as the osc-mod-effect when you fully turn up the mod-wheel, you would probably get the result you desire by encreasing the value of R27 appropriately. You could just install a trim-pot (100k would probably do) in series with R27 and then adjust that accordingly.

Dr.T · Post by **Dr.T** » Tue Jun 13, 2006 8:19 am

hm .... just as a afterthought to my last post:

The Rogue technical service information issues in 1981 by Moog Music Inc.Co. specifies the bend range to 1/- 7 semitones. This would imply that at least the factory issue Rogues indeed had a bend range of much less than +/- an Octave. Which doesn't say that there aren't a lot of Rogues out there which have been modified to bend up and donw some more ......

writeroxie · Post by **writeroxie** » Tue Jun 13, 2006 11:01 am

Dr.T wrote:@ writeroxie:
thanks for correcting me - since you have the Rogue there you are the one to judge this! I just don't remember any of the Moogs I owned in the past (Prodigy, Rogue, Multimoog) to have that kind of bend range ...... I apologise very much if I have disseminated incorrect info!

haha, no need to apologize... i was merely naming one moog that i actually know has a full octave pitch wheel. The Source (not the rogue).

Dr.T · Post by **Dr.T** » Tue Jun 13, 2006 12:16 pm

Riiiight! I didn't read well enough either - you did write "SOURCE"!

One more "thumbs up" for the Source, then! ......... hm ..... one needs a lot of hands for all the "thumbs up" the Source is getting

I learned something today - very good!

Take care,

T.

xtudis · Post by **xtudis** » Wed Jun 14, 2006 6:00 am

cool,

Although my post wasn´t clear enough for you guys (DR T and Writeroxie), you've just answered the questions!!!

Again thanks for your help.

BTW where i can get a manual for the Rogue? (not the service one).