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BOSS OC-2 synth mod with sound clips

Outside of a gate, not entirely. A lot of it gets lessened by turning the bass down on the tone control....not the effect bassists want ;)

Turn the VOLUME down on the instrument, that effectively gates the synth-mod tone. But as previous stated it negatively affects the dry and non-synthmod sounds.

The synth mod basically solos the raw oscillator. So it's a hard on/off sound, no dynamics, no real control over output volume via playing, just a note tracking on/off control over the oscillator sound.

But it's badass!!! Well, at least different. :) You can get all sorts of interesting sounds blending synth-mod OCT2 with normal or synth-mod OCT1.

Sound clips towards the very end of this page: http://cgraham.com/chris/music/sound_clips.htm
 
I have a small trim-pot mounted on the switch, that turns the synth-mod on/off. Had to put a piece of tape on it to prevent shorts, but apart from that everything fits neatly.

If you don't bypass it when turning off the synth-mod, you'd get terrible tracking/octave-jumping all over the place.

So, just to be clear: After adding this trim pot, the pedal doesn't make noise between notes any more, and you still get that awesome square wave sound?

If this is the case I am very interested in seeing your instructions!
 
I still would like mine to gate harder - that's why I began designing an external gating circuit, but couldn't fit inside the OC-2. It stays quiet between notes, but there is some fizz on note attack and release i'd like to get rid off.
I would like one of these. Just to clarify, it's possible to have the raw synthy sound, but it's still clean and quiet in between notes, not all sloppy and useless like an oscillating fuzz?

If someone has figured it out, I would pay for one, for sure.... Hit me up. I can find a spare oc2 yo donate....

J

Hehe I'd love to build one for you John, I'm a big fan of the stuff you play with Nerve, but I guess it isn't that practical, me being from Europe.

(Off topic, do you have any plans to gig in Northern Europe any time soon?)
 
Got a brilliant idea while working on that math assignment! Fixed the negative envelope follower to just below bias voltage. This effectively gates the synth signal about as hard as a woolly mammoth :D Only problem is that it gates harder the higher you play (note/tone and there is a limit to how open the gate can be. (these things are quite easy to solve, there just isn't space enough in the OC-2)

I'm writing a schematic at the moment, but don't know if I will finish it today.

EDIT1: Oh yeah and there is also an easy mod to solo OCT-1 and more than double the volume!

EDIT2: Sound clips:

 
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Sorry for triple posting, but thought a bump with schematics was fitting:
oldschem.jpg

Original from:Boss OC-2 Dual Octave Down Guitar Pedal Schematic Diagram

Synth%2520mod.jpg

There are two mods here, my "bleed less"-synthmod and my "hard gate"-mod.

Explanation:
--Break connection between the red wires.
--Connect (1,1) in the first schematic to 1-1 in the second schematic. (1,2) to 1-2; (2,1) to 2-1 and (2,2) to 2-2
--Both switches are shown in "stock position".
--Vb is the bias-voltage, available between R45 and R25.
--This symbol: _|_ means "ground", connect it to the casing, or anywhere with the similar symbol in the b/w schematic.

How it works:
-Bleed less
--The problem with bleeding occurred (to some), because a wire with a very hot signal, with lots of overtones, was passing physically close to the clean octave.
--This mod uses the phase inverter. Instead of "flipping" (phase-inverting) the clean signal around the bias voltage, a fixed voltage is flipped - thus a squarewave is outputted.
--The OCT-1 squarewave is routed through the filter, this would need bypass, if one wants extra face-melting sounds.
--The OCT-2 automatically becomes "synthed", but not with a squarewave.
-Hard gate
--Each peak of the incoming signal is compared to a threshold. If the limit isn't reached, no sound leaves the box.
--The OC-2 tracks pitch on the rising peak. The gater on the falling. This makes it possible to gate instantly.
--There is one drawback: I had to make a little workaround, so unfortunately it gates a bit harder on higher pitches.

Unfortunately I did not take any pictures during the assembly. so can't make a good pic-torial about how to perform the mod.

Any questions are welcome.
Happy modding!:hyper:

EDIT: (Clips in a decent quality will be recorded this weekend.)
 
So is it recommended to buy a second oc-2 for this? (whether it's already been modded or not)

Also do we know if it's possible to mod the pedal so the direct level feeds oct-2? I'd love to be able to use oct-1 factory and oct-1 synth at the same time using just one pedal. I need to take a look at the schematic, but if anyone has any info about this please share!
 
HEY GUYS. I really like my OC-2. I don't really feel I need the synth mod. What I wish I could change however is the volume envelope. I like the natural sustain of my bass, so I can control the ADSR with my hands. Is there a way to keep the tone of of the OC-2 but get rid of the volume envelope circuit, if only just for oct-1? If anyone has done this, or thinks they could do this, please let me know!
 
HEY GUYS. I really like my OC-2. I don't really feel I need the synth mod. What I wish I could change however is the volume envelope. I like the natural sustain of my bass, so I can control the ADSR with my hands. Is there a way to keep the tone of of the OC-2 but get rid of the volume envelope circuit, if only just for oct-1? If anyone has done this, or thinks they could do this, please let me know!

Experiment with a compressor in front of or behind the OC-2 to solve that issue. Note you can also change the tone of the OC-2 by overdriving it's front end. Slam it with a huge DB boost in front to push it towards a fuzzier tone. I have some sound clips on my general clips page of the OC-2 being slammed in that way.
 
I did the synth mod (via instructions from YouTube) on my OC2 (Taiwan) and have a few questions:

When the synth mod is bypassed (normal mode), there is a slight "synth mod sound" that is very quiet in the background. W T F is happening here?

When is synth mode, there is some octave jumping... If I let a note ring it can go up and down an octave (even with only one octave engaged). Any tips?

I play a Stingray or a EBMM Sterling, so both basses are pretty hot.

To come clean, I didn't read the whole tread cover to cover. THANKS!