cyclone tt-303 open source mod project

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chrix
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cyclone tt-303 open source mod project

Post by chrix » Wed Jun 24, 2015 5:27 am

Hi fellow wigglers!

A couple of weeks back i opened up my tt-303 to have a look at the pcb and noticed some pretty obvious terminals that i wanted to hook up to jacks.. the other day I did!

Found some really really cool possibilities and thought i'd share it with you.

Would be cool to create an "open source" mod collection project here!

the project name right now is GodBird :) or maybe it should be DemigodBird hahaha

Sorry for the dodgy video and that it's on its side, but will give you an idea.

[video][/video]



if anyone's interested i'd be happy to make some instructions on how to do it.

in the video i'm using RYO's genius passive multiple to attenuate the signals. my plan is to incorporate attenuators within the mod. My multimeter is gone at the moment so have had no chance to measure what actually happens and how much voltage is coming out of the different terminals…

well, check it out, would be cool to see if anyone else has tried this?

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amnesia
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Post by amnesia » Wed Jun 24, 2015 5:58 am

excellent stuff. I am keen to know what you did and please keep us in the loop on any new mods

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Post by chrix » Wed Jun 24, 2015 6:22 am

amnesia wrote:excellent stuff. I am keen to know what you did and please keep us in the loop on any new mods
Thanks Amnesia!

As far as i know, there are no documented mods of the TT-303 online, been searching but haven't found anything, just the DevilFish-guy in australia talking about doing R&D for a devilfish TT-303.

My deepest respect for the DevilFish guy, hands down. But it surprised me how relatively easy it was to do these mods. I would have done more if i'd had more jacks here at home, but i'm out! :)

Basically on the PCB there are a few terminals, some bigger some TINY. i hooked some up to jacks and grounded on the GRND2 terminal. (there is another digital ground on the far left of the PCB).

I also probed around here and there with a pair of old headphones and found that the right pins of the ENV and ACC pots outputs the unattenuated envelopes, and the middle pin outputs attenuated envelopes. So you can choose which one you want to access, or get them both.

PLEASE NOTE: Some settings completely drains the power of the tt-303 and to fix this goes beyond my knowledge of electronics. maybe it would be possible to get some attenuverters in there and buffer some draining signals, and also to put resistors in to battle shorts to ground at some settings. any input on this would be highly appreciated!

Posted the video today and I already have two orders for people in sweden wanting me to mod their units :) So i'm going to keep trying things, hopefully I won't fry my unit and i'll be able to present a finished package of mods.

a "DemiBird" mod pack hahaha

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amnesia
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Post by amnesia » Wed Jun 24, 2015 6:37 am

Yeah I was hoping that Robin Whittle would do a Devilfish mod but seems not to be the case.

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mckenic
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Post by mckenic » Wed Jun 24, 2015 7:32 am

HELL YES!

I f00kin love it!
Please keep going - VERY interested in whatever you come up with!!!

The random pitch and filter out -> mix in, filter->VCA in were bloody wicked! :tu:

Imna have to buy a 2nd TT to do this to it :hihi:

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Post by chrix » Wed Jun 24, 2015 9:30 am

mckenic wrote:HELL YES!

I f00kin love it!
Please keep going - VERY interested in whatever you come up with!!!

The random pitch and filter out -> mix in, filter->VCA in were bloody wicked! :tu:

Imna have to buy a 2nd TT to do this to it :hihi:
It's a dead easy mod brother, you won't need a 2nd one, it all goes back to original when nothing is plugged in!

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Post by c1t1zen » Wed Jun 24, 2015 2:40 pm

Robin Whittle AKA DevilFish dude is working on a devilfish mod for the TT-303 but life has gotten in the way he said to me. It'll get done.
I think he like me was hoping they would have a version 2 released without the sequencer bug...or was that fixed in the firmware update?

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Post by chrix » Wed Jun 24, 2015 5:06 pm

c1t1zen wrote:Robin Whittle AKA DevilFish dude is working on a devilfish mod for the TT-303 but life has gotten in the way he said to me. It'll get done.
I think he like me was hoping they would have a version 2 released without the sequencer bug...or was that fixed in the firmware update?
I think it was fixed in a firmware update but I don't know - I haven't been able to update mine to be honest, i'm on a too old OSX system, and i heard it really only works on a pc anyway..?

Let's be clear - what Robin Whittle does is to completely over-haul the 303 from the ground up, he replaces any component that will deteriorate over time and makes the "plastic toy" that an original 303 is into a solid musical instrument that could be toured extensively and hold the test of time. know what I mean? Once again - respect to the man!

What i'm trying to do is take the "plastic toy" that the TT-303 is and play around with it and maybe make it into a more versatile toy to play with :)

If i happen to fry it… ok then i'd have to get another one, and I can cause it's a TT, not a TB :)

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Post by chrix » Wed Jun 24, 2015 5:13 pm



another video btw - this time some modular interaction

the 12db output goes out to a VCA which the accent envelope opens up, into a spring reverb. the accent gate clocks a touring machine sequence going via a penrose quantizer to a pittsburgh synth block. etc etc

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amnesia
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Post by amnesia » Wed Jun 24, 2015 5:35 pm

I couldnt do the update on OSX but worked fine on a friends Windows lappy.

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Post by computer controlled » Thu Jun 25, 2015 2:17 am

The sequencing bug was addressed in the latest update.
Stuff: SH-01A . TR-8S . MX-1 . D-20 . Waldorf MicroQ - Waldorf Microwave II . Ensoniq EPS 16+ . Yamaha MODX6 . MPC Live . Avalon BassLine . Behringer Neutron . Behringer MS-101 . Behringer Pro-1 . Behringer K-2 . Behringer TD-3 . Microvolt 3900 . BeatStep Pro . Keystep .

chrix
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Post by chrix » Fri Jun 26, 2015 5:19 pm

I'll open it Up and snap some photos when i have more time but if you're in a hurry to try it here's what to Do:
Drill some holes in the Top (watch Out i almost busted the multi-wire jumper thing!) Put 3,5 jacks in.

along the line above the tempo pot is a good place, as well as straight over the Bass Bot text on the right.

On the PCB there are marked terminals YES marked terminals people!!! run wires from the 3,5 tips to the terminals You Want hooked Up, and ground all to GND2!!! NOT digital GND on the left!

The mid and right/clockwise terminals of the ACC and ENV pots output envelopes. The right unattenuated and the center attenuated. Or Maybe the other way Around actually. You can probe the signal, that's what i did to find it, hook Up cheap headphones to clips, ground at the sleeve and probe w the tip. That's pretty much it! :party:

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Post by LektroiD » Sat Jun 27, 2015 5:13 am

Anyone know a way to bring the gain of the squarewave up? On the TB the squarewave is louder than the saw, on the TT, it is quieter (well mine is at least)… Does anyone know a way to increase the gain on that waveform (or maybe lower the saw, then increase the overall gain of the unit)?

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Post by Nordcore » Sat Jun 27, 2015 6:30 am

Have you checked the signals against the values stated in the Roland service manual?
(=> then you know what to fix. )

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Post by chrix » Mon Aug 03, 2015 4:56 am

DemiBird mod is now in final beta testing!

Started probing the J5 jumper and wow there's soooo much you can do w this.

For some reason the osc pitch mod terminal on my unit stopped working, i have no idea why. I know it did at One point When i was probing Around.

Anyway check some videos Here if you're interested.


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Post by mckenic » Mon Aug 03, 2015 8:32 am

:banana: :banana: :banana: :hail: :tu:

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Post by abortifacient » Sun Feb 21, 2016 12:46 am

I've been looking for ages for someone modding the TT303, and found this today. Looking great! :hail:

On your instagram vid, hans acid said he'd done
"-Devilfish like resonance, 2 different settings
-vca overdrive
-overdrive , keeps the low end on!
-vco mute , the vcf will self oscilate
-second stage hp filter
-filter FM with the wave forms - accent launch button"

I was wondering if you could share any info on the points on the board for these? I'd kill for the devilfish resonance.

On the Volca Bass, I did a similar FM modulation of the cutoff, by sending VCO out to the cutoff pot. Crazy squelchy resonance on the volca bass, loving it!

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heapish
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Post by heapish » Mon Feb 22, 2016 5:18 pm

I would like to see...
Oscillator kill/Audio input into VCF
VCF CV
ENV CV
DECAY CV
ACCENT CV

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Post by PWM » Tue Feb 23, 2016 1:53 am

heapish wrote:I would like to see...
Oscillator kill/Audio input into VCF

On the TB-303 this is possible by putting the waveform switch in the midle. This is quite fiddly but works great.

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Post by Troubleshooter » Tue Feb 23, 2016 4:47 am

Why not look at the x0xb0x community...

I did most of those mods out there. I have built 4 x0xb0xes so far to apply them on.

Since both machines are replicas of the analog TB-303 section I wouldn't hesetate to use them in the TT.

I recomend:

Bass boost (just replace 2 caps.) turns the bass-line into an actual bass machine.

The recommended 4 high hfe trannies in the VCO/VCF. Your machine really starts to sound like a real 303. I socket those 4 important transistor locations for a good reason.

Extended filter range. Just 1 resistor over another. Great to have a filter that cuts away all the way down...

VCF audio input and VCO mute: Turns any instrument into an acid line.
Great for implementing the thing into a modular system.

If you have a modular system I recommend a accent-gate output.


http://www.subatomicglue.com/x0xl0g/mod ... guide.html

I do recomend to skip the devil fish hype and use external stopboxes for distortion, fuzz and overdrive. So much more coloration using diffrent stomp boxes. The boss- bx-series mixer gain saturation and MXR distortion plus are my favorites.

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Donderdag
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Post by Donderdag » Sat Jul 09, 2016 4:44 am

Have been planning on modding my TT303 for some time now after coming across this thread. Since there doesn't seem to be much documentation here or elsewhere (that I'm aware of) I thought I'd start off my contribution by listing all the obvious connections on the TT303 along with their function.

I can't dig into this for a couple weeks so there are a lot of single question mark items (meaning "I'm not sure") and double question mark items (meaning "I have no idea"), but I plan on updating and fleshing this out once I have time to dig into these mods.

I'm a big advocate on the free dissemination of this sort of knowledge and am not looking to make any money on this, just to spread the modding love, so please if you feel the same and have info you can share for this project do chime in with you two cents.
  • SAW - Raw saw wave output
    SQ - Raw square wave output
    VCC - ??
    MCU61 - Clock point?
    J2 - Header for what??
    SLD - Slide voltage out?
    GATE - Must be gate in? Already have gate out?
    VCO_CV - VCO CV In, looks like
    RESO_FB_SIG - Resonance feedback signal. Input I guess?
    CO_ENV_CV - CV of filter cutoff envelope
    CO_POT_CV - CV of filter cutoff something??
    CO_ACC_CV - Some kind of CV of cutoff accent. In or out?
    VCA_ACC_IN - Input signal which affects the VCA when the accent fires?
    VCA_CTRL - CV in of VCA?
    VCF_CAL - ??
    TP2 CV - ??
There are also various ground and voltage points:
  • DGND - Digital(?) ground
    GND1, GND2 - Ground
    12V, 6V, 5.33V - Voltages
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Post by PWM » Sat Jul 09, 2016 7:02 am

I added a Saw to VCF frequency CV with attenuater to my vintage 303. Love this mod! Chose for the saw to modulate the filter becouse I use square more often then saw.

Also, a sub OSC circuit, Square into a CD4013 is very easy to add..! Moar bass! :D

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Post by bartleby » Tue Jul 26, 2016 10:03 am

chrix wrote:the accent gate
Troubleshooter wrote:If you have a modular system I recommend a accent-gate output.
any tips on how to do this on a tt-303 would be much appreciated.

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Post by Donderdag » Sat Aug 20, 2016 3:11 am

Alright folks, finally managed to get out the scope and signal generator last weekend and started poking around the TT-303. Here's what I found.

Cool stuff:
  • SAW - Raw saw wave output, 4.5 volts pp.
    SQ - Raw square wave output, 3.5 volts pp.
    SLD - Slide gate output, 3.5 volt pp with length proportional to slide time.
    ACC- Accent gate output, 3.5 volts pp. Always high until an accent, then drops to zero volts until next note.
    VCO_CV - VCO CV In. Same as TP2 CV.
    RESO_FB_SIG - Input to resonance feedback.
    CO_ENV_CV - CV input for filter cutoff, mixed with envelope CV.
    CO_ACC_CV - CV input for filter cutoff, mixed with accent CV.
    VCA_ACC_IN - CV input for VCA level, mixed with Accent CV.
Boring or weird stuff:
  • GATE - Gate out. Already have a jack on the back for this.
    CO_POT_CV - Seems to be a CV input for filter cutoff but very extreme even with low voltages.
    VCA_CTRL - Seems to be CV for VCA gain, but very unstable and causes the 303 to stop and reset. Avoid.
    DEC - Seems to be CV for decay, but also very unstable and causes the 303 to stop and reset. Avoid.
Still unknown:
  • VCC - Still no idea, does not seem to respond to input nor is anything coming out.
    MCU61 - No idea, same response as VCC.
    VCF_CAL - Need more investigation
I also completely missed the J5 header (not pictured), which probably has a lot of interesting connectivity. The middle legs on the envelope, decay, and accent pots are good points to pickup their respective CV signals for output as well.

I'm moving continents soon so won't get to this until the fall, but my plan from here is to take everything from the "Cool" list, plus the envelope, decay, and accent CVs and connect these to a breakout box with 1/8" jacks. Attenuators will be handy/essential for some connections so I'll build a couple of these too, either into the breakout box or directly into the case itself. I also plan to document the whole thing so should be easily replicated if you have basic soldering skills.
Donderdag wrote:Have been planning on modding my TT303 for some time now after coming across this thread. Since there doesn't seem to be much documentation here or elsewhere (that I'm aware of) I thought I'd start off my contribution by listing all the obvious connections on the TT303 along with their function.

I can't dig into this for a couple weeks so there are a lot of single question mark items (meaning "I'm not sure") and double question mark items (meaning "I have no idea"), but I plan on updating and fleshing this out once I have time to dig into these mods.

I'm a big advocate on the free dissemination of this sort of knowledge and am not looking to make any money on this, just to spread the modding love, so please if you feel the same and have info you can share for this project do chime in with you two cents.
  • SAW - Raw saw wave output
    SQ - Raw square wave output
    VCC - ??
    MCU61 - Clock point?
    J2 - Header for what??
    SLD - Slide voltage out?
    GATE - Must be gate in? Already have gate out?
    VCO_CV - VCO CV In, looks like
    RESO_FB_SIG - Resonance feedback signal. Input I guess?
    CO_ENV_CV - CV of filter cutoff envelope
    CO_POT_CV - CV of filter cutoff something??
    CO_ACC_CV - Some kind of CV of cutoff accent. In or out?
    VCA_ACC_IN - Input signal which affects the VCA when the accent fires?
    VCA_CTRL - CV in of VCA?
    VCF_CAL - ??
    TP2 CV - ??
There are also various ground and voltage points:
  • DGND - Digital(?) ground
    GND1, GND2 - Ground
    12V, 6V, 5.33V - Voltages
Image
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Image
Image
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Venetian Snares wrote:I wanted it to sound like a giant hovering boulder on fire
---------------------------
Seize the Carp
Stuff for sale
My Soundcloud

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Donderdag
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Post by Donderdag » Sat Aug 20, 2016 3:15 am

bartleby wrote:
chrix wrote:the accent gate
Troubleshooter wrote:If you have a modular system I recommend a accent-gate output.
any tips on how to do this on a tt-303 would be much appreciated.
If you solder the tip of a 1/8" jack to the ACC pad on the PCB and the ring of the 1/8" jack to the GND1 or GND2, then you're good to go!
Venetian Snares wrote:I wanted it to sound like a giant hovering boulder on fire
---------------------------
Seize the Carp
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