Little Phatty CV Out mod pitch bend use?

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EMwhite
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Little Phatty CV Out mod pitch bend use?

Post by EMwhite » Thu Jan 29, 2015 10:29 am

Can anybody with the LP CV Out mod confirm whether or not Pitch bend wheel and glide affect the Pitch CV Out voltage?

When I had my Phatty (which was a Tribute) I recall having directions on how to move solder points to a SUM_A Out or some other test point but later learned that the directions were not for Tribute but rather, for a Stage.

Were the factory shipped CV Out units strapped to provide this feature or is it just key press pitch.

Thank you
'76 Minimoog, Taurus 3, Oberheim FVS + Son of 2-voice; Sequential ProOne; Juno 106; Moog Model 15; Kurzweil 250; Hammond M3; and a handful of Fender Basses Flickr!

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_DemonDan_
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Re: Little Phatty CV Out mod pitch bend use?

Post by _DemonDan_ » Thu Jan 29, 2015 1:06 pm

I have a Late-2009 Sweetwater Solar Phatty (which came stock with CV Outs).

Here (@3:55) you can hear that the PB Wheel is *not* going to the PITCH OUT CV jack:

https://www.youtube.com/watch?v=qkm-2OuIOhI
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EMwhite
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Re: Little Phatty CV Out mod pitch bend use?

Post by EMwhite » Thu Jan 29, 2015 2:39 pm

Late 2009 is early for CV out. I still have a note in my mailbox from July 2009 in which Amos said that they were still working out what the jack plate would look like; I was there in late summer IIRC to drop off my tribute. It was very much a 'solder patch points to surface mount resistor' affair.

Guessing there was a later revision of the analog board that may have offered Pitch bend and Glide as standard course but maybe not.

Thanks for the reply, I saw your clip on the original posting over on the other forum.
'76 Minimoog, Taurus 3, Oberheim FVS + Son of 2-voice; Sequential ProOne; Juno 106; Moog Model 15; Kurzweil 250; Hammond M3; and a handful of Fender Basses Flickr!

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_DemonDan_
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Re: Little Phatty CV Out mod pitch bend use?

Post by _DemonDan_ » Thu Jan 29, 2015 2:48 pm

EMwhite wrote:Late 2009 is early for CV Out. I still have a note in my mailbox from July 2009 in which Amos said that they were still working out what the jack plate would look like; I was there in late summer IIRC to drop off my tribute.

Guessing there was a later revision of the analog board that may have offered Pitch bend and Glide as standard course but maybe not.
In that case, I too would love to know if anyone has a Little Phatty PITCH CV Out that takes Pitch Bend & Glide into consideration.
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DonutDude
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Re: Little Phatty CV Out mod pitch bend use?

Post by DonutDude » Thu Jan 29, 2015 3:22 pm

Don't remember when I had the CV outs installed on my LP stage II but it was later than 2009. Glide does work but not pitch bend.

EMwhite
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Re: Little Phatty CV Out mod pitch bend use?

Post by EMwhite » Thu Jan 29, 2015 3:43 pm

Here are the instructions I rec'd from Moog Engineering. I never went through with trying to modify the mod it because the Sub37 release [last year] F O R C E D me to sell my Tribute. Then of course I did not have the patience to wait for general availability to improve so I blew the $$ on 2 or 3 MOS-LAB modules.

But here are the instructions, provided with a strong DO NOT TRY THIS AT HOME unless you talk to Moog support first, are adept at surface mount soldering/desoldering/and are prepared to void your warranty assuming you still have one :D. The procedures is also likely to vary by model/rev of circuit board:

From Moog:

The implementation of the CV out mod then was not quite perfected when you had it done, but there is a pretty easy (assuming you are handy with a soldering iron) way to mod it so that you get all pitch modulation effects through the Pitch CV output .

If you open up your LP, you should see an Orange wire soldered to R121. That is the wire that carries the Pitch CV, and if you move it to the SUM_A test point (TP9) then you will have the Pitch Wheel, Glide, any Pitch modulation and Fine Tune all sent to the Pitch CV output. All of these can be disabled in the firmware, so you can turn any of these on/off as you please.

I later rec'd conflicting instructions for the Tribute vs. Stage but to be honest, it's all a blur right now; the additional detail was:

SUM_A Test Point (TP100) is connected to both pin 14 of U63 and R159 (the side that is not connected to pin 13 of U63).

Here is a pic if you like that sort of thing:

Image
'76 Minimoog, Taurus 3, Oberheim FVS + Son of 2-voice; Sequential ProOne; Juno 106; Moog Model 15; Kurzweil 250; Hammond M3; and a handful of Fender Basses Flickr!

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_DemonDan_
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Re: Little Phatty CV Out mod pitch bend use?

Post by _DemonDan_ » Thu Jan 29, 2015 4:19 pm

Very cool, EM!

But I've yet to brave soldering/desoldering surface mount parts; so I'll probably chicken out ;-)
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EMwhite
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Re: Little Phatty CV Out mod pitch bend use?

Post by EMwhite » Thu Jan 29, 2015 5:16 pm

If I kept the LP, I would have gone through with it, at this point I'm eager to learn if I can buy one good to go. There are still retailers with, dare I say, new-old-stock.

If I get an answer, I'll update this thread.
'76 Minimoog, Taurus 3, Oberheim FVS + Son of 2-voice; Sequential ProOne; Juno 106; Moog Model 15; Kurzweil 250; Hammond M3; and a handful of Fender Basses Flickr!

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DonutDude
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Re: Little Phatty CV Out mod pitch bend use?

Post by DonutDude » Thu Jan 29, 2015 6:09 pm

For what it's worth, I was able to find documentation that Moog did my CV mod in May of 2012. So up to that point no pitch bend over the cv pitch out, only glide.

denoiser
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Re: Little Phatty CV Out mod pitch bend use?

Post by denoiser » Thu Sep 13, 2018 1:55 pm

I know this is a very old thread. However, in case anyone is interested, let me explain how I modded my LP Stage II's pitch CV out to include fine tune, glide, PW and the pitch from the MOD bus.

Notice that my SN is below 8100 (see https://www.moogmusic.com/products/phat ... dification) so the CV out modification is performed by soldering cables and not by plugging the connectors because there are no sockets on the motherboards.

Like someone said, I moved the orange cable (pitch) to TP9 (also labelled SUM_A) but the voltage was about 1.2V/oct and lowering the trimpot in the CV out board was not lowering it.
To lower it down, I put a 100K trimpot between TP9 and AGND and connected the middle pin to the orange pitch cable (voltage divider). Then, firstly I adjusted the trimpot it until I got a value slightly below 1.0V/oct and secondly adjusted the trimpot in the CV out board to get a precise value of 1.0V/oct.

Seems it's working fine.

This mod is based on the information found in this thread.
No official information is used and this mod should not be considered as such.
Do this at your own risk.

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