Moog Music Forum

Could only upload three images so here's some more of the modules I mentioned which I just built...

Hi folks, My System 15 reissue is expanding..! This is how it looks now. I've had to have another cabinet made for some extra custom modules and some overflow modules from the '15' cabinet..! I put the filters & noise, the fixed filter bank and the attenuators up there along with an original R.A...

My reissue System 15 has switchable mains voltage so I would assume the Model 10 should also.
Would make sense..?

curious if anyone has improved the range switch circuits on the 901a's, to make them more accurate? The 'fixed control voltage' on the 901a is done with resistors whereas the 'frequency range' on the 901b is done with capacitors. The 901a should have quite accurate switching really... much better t...

Probably normal... my 901's drift quite a lot, some of them more than others though. Their sound makes it totally worthwhile sticking with them and not upgrading to the 921's. I modified mine adding a front panel control in the place of the lower of the three inputs sockets on the 901a so I can basi...

I have another video of some more progress with the Modular preset box I am building. On this video I'm doing a dual test - testing both the preset box controller, now installed in the case and also the power switching circuit on the breadboard to check if it will actually work with the controller. ...

I just finished another part of the project today... It's the 'latching' control unit which I have just finished putting together for the Moog Modular preset box I am building. It will have eleven control lines coming in from the push-button unit. 10 outgoing lines will go to the 10 preset cards and...

Cool reverb :) May I ask another question? Did Bob keep the CA3019 based expo solution of the 901A when he transferred this to the 901B oscillator or did he change this to something like the heated transistor array solution like in the Mini then? No that diode array is bypassed - there is a tempco ...

Ok, but are they still in production or under copyright protection? These are basically copies of Emerson's Modular service manual with notes by Bob as he worked on it over the years, I suppose he also added the drawings for the new module modifications etc... Like I said, I was given them in confi...

I'd love to see pictures (and schematics of course). Why don't you run a web site? If I could I would post photos of my progress but as I noted earlier, this forum doesn't allow it. I have all the schematics and drawings and notes - they also include schematics of the revised 901A&B controller ...

Ok. What are the voltage sources? All voltage sources are derived from within the preset box itself... in fact, each card provides different ones via the settings. Other variables, such as all the EG settings, and the resonance actually interface into each module directly. The CP3 mixer level setti...

How does it work? A selectable group of CVs connected to modules, especially like sequential switches etc.? No - nothing like that. There is what you could call a 'CV feed' to the node of the osc controllers for the fine tuning and also the node of the filter for fixed control voltage level - but t...

Hi folks,

I'm currently building a 'preset box' based on the 1969 'Jazz In The Garden' designs for my Modular Moog's.
I'd like to share photos - pity the board doesn't allow it anymore.

till wrote: ↑Sat Dec 12, 2020 6:27 am According to the vintage Moog Modular Owners Manual and the Frontplate (for left and right position) the positions are (left to right):
Weak - defeats sync - Strong

Thank you...

Hi folks, Question for anyone owning an original vintage 921B oscillator. I have the reissue System 15 and I noticed the synch switch has three positions. The service manual shows two positions WEAK & STRONG... it does not suggest a centre position. Can anyone please confirm for me that there sh...