“I bought this drum machine in 2006 from a guy in the UK called Matt Wells who had performed some serious circuit bending on it. The circuit bent mods are enclosed in a dual-box housing to the right hand side of the machine and include 19 rotary pots, 3 two-way switches and 1 three-way.
These are as follows:
1. Klik Drum. This allows the bass drum envelope to be pitched so it can be heard as anything from a punchy boom to a pronounced click that really cuts thru your speakers. The extreme click only occurs though only in the last ¼ of the pots travel and so is easily avoided if not required. This is the most simple of all the mods and least versatile. I tend to set it for a suitably deep bass drum and leave it there. This is not where the fun is at, though you could use it to make the most extreme form of glitch-tronica, just watch your speakers.
The snare drum on the other hand is another thing entirely…
2. Snare Tone. Pitches the snare across a wide range.
3. Snare Snap. For those who wished the 606 snare could sound more like an 808, wish no more.
4. Snare Decay. 10 turn pot, side mounted, for further sound shaping possibilities.
5. Snare Filter. Can be adjusted from fully open down to near silence.
6. Tomz Tone.
7. Tomz Tone.
These two above are interactive two-way switches affecting both Toms.
8. Tomz Distortion. Three-way switch. Off at centre, left for minimal distortion or right for maximum.
9. Tomz Distortion Level. So you can dial in control of the above, also dependant on the Tomz Tones.
10. Cymbal Tone.
11. Cymbal Decay.
12. Cymbal Resonance.
13.14.15.16. Row of 4 Hi-Hat Oscillators.
These can make the hi-hats sound very metallic, more sci-fi SFX than traditional hi-hats.
17. Hi-Hat Decay.
18. Hi-Hat Decay.
These two mods are side mounted and interact with each other, though I find the top one has a distinct effect on decay whereas the 2nd one only adds noise dependant on the 1st one.
19. TRX-666 Rotary. This is a 7 position rotary pot which incrementally adds global feedback and distortion from minimum/off to maximum. Some settings produce sustained drone tones and add harmonics and feedback to some drum sounds that makes the machine sound more like a malfunctioning synth than a drum machine, especially the toms.
Can be used for some great sound FX though.
NB. Be aware that at extremes all these mods will add noise to the outputs, at maximum extremes these can produce peaks considerably higher than the regular output level and so I recommend leaving plenty of headroom when playing or recording, probably 12-20dB for a digital system.
Note also that as this is circuit bent some pots can seem to have little effect for half their travel and then produce sudden changes in tone, feedback, output, etc and this is often dependent on other pots and switches. I spent a few days familiarising myself with it and being cautious, so that I knew where the hot spots were. The noise in the circuitry can be kept to a minimum but generally that’s where the fun is at so it pays to learn how to use the pots carefully around these hot spots, ok.
If you want a clean sounding 606 then buy another one please.
The Individual Ouput mods (all now labelled) had already been installed also when I bought it and these are great as they allow for additonal processing of the sounds over 5 outputs on 3.5mm mini-jacks as follows:
1. Bass Drum
2. Snare Drum.
3. Toms.
4. Cymbal.
5. Hi-Hats.
This mod costs £50 fitted. I will include the 5 mini-jack to ¼” jack adaptors I bought for them also.
In addition I bought and installed the following two mods from respected Roland mod company, Analogue Solutions:
MIDI trigger kit.
This allows triggering by MIDI of all the 7 drum sounds of the TRX-666.
MIDI channel is programmable by sending note on message- currently set for Channel 1.
MIDI note assignment is fixed from manufacturer and is as follows:
Bass Drum C3
Snare Drum D3
Lo Tom F3
Hi Tom F#3
Cymbal A#3
Open Hi-Hat C4
Closed Hi-Hat. C#4
Note that this is to trigger the sounds and is not velocity sensitive- I don’t know of any TR-606 that is…
Though accent IS programmed for a pattern step when velocity is greater than 80. Simple enough.
The optional MIDI thru is installed also for those that need it, as is the MIDI to DIN-sync trigger which allows you to use the MIDI start message sent to the TRX-666 to trigger other Roland X0X gear and run it in sync. Very useful.
To use the MIDI trigger it’s a simple flick of a switch to the down position to disable the internal CPU and set the SYNC to INPUT. To use the internal sequencer set SYNC to OUTPUT and MIDI switch to central.
Note that whilst all the pattern LED’s work, they have to be pressed towards the top for them to be activated/deactivated. This is common due to age of these machines and whilst you can buy a replacement set cheap through Ebay, I never bothered because I have far more flexibility triggering by MIDI from either my P3 sequencer or Ableton Live. The 606 onboard sequencer maybe simple enough but you can soon be very limited by it…
NB. In checking the machine recently I have noticed that when I power up with MIDI trigger disabled- i.e. if required to use to internal sequencer, sometimes the machine will not function as it should.
Then if you power down, disconnect the psu and then re-power, it will work as it should. As a result the internal sequencer is temperamental now it seems and I WOULD NOT RECOMMEND buying this machine if you prefer to use the on-board sequencer. Buy a standard TR-606 instead, ok!
The MIDI trigger always functions 100% and I would suggest you only bid to buy this machine if that’s how you are happy to work, as I did.
This mod is a £79 kit or £119 fitted. Paperwork is included.
The Trigger LED mod kit is also installed and shows when each of the seven drum sounds is triggered.
(All are now labeled). Note that whilst there is no LED for accent if accent is programmed the LED will light brighter on that step- very useful also to have this visual aid, as well as looking cool. I used green LED’s instead of the kit ones…
The only problem with this mod is that whilst they all work as they should when using the internal sequencer, when using the MIDI trigger mod above (as I did) the Lo and Hi Tom LED’s do not light up.
I have tried to remedy this but have had no luck and can only think it must be something to do with the extensive circuit bend wiring done to the toms, that for some reason only defeats these two LED’s when using the MIDI trigger. Something I’ve been happy to live with/out…
This mod is a £20 kit or £38 fitted. Paperwork is included.
The original User Manual is included with this machine, which is rather rare and though it does have a number of pages towards the back stained (30-40), these are generally on the pattern diagrams for the advanced course section and ALL print & diagrams are still easily readable under the stain.
In good condition for it’s age and is available free online also.
Included too is the even rarer 4 page preliminary release guide, dated Sept ’81, which opens up as a gatefold titled: TR-606. The new rhythm machine that you program yourself.
This is in excellent condition.
A wall wart style external PSU will be required as mine is now to be used for something else. This can be easily obtained from an electrical store but MUST be 9 Volts. Mine was a Uniross 9V@300mA, as the maximum current draw by the machine is stated as 150mA.
The machine can be run off batteries (4 x C type @ 1.5V) though I have never done so as on the spring side there is a small amount of green residue indicating a small previous leak. However, there is no sign of this anywhere else but on the spring end itself. Absolutely nothing in the battery compartment or the machine itself, ok.
I have been thorough and honest in my description of this machine.
The fitted mods alone would cost you £210 in addition to a standard TR-606.
The circuit bent mods are not exactly priceless but are certainly unique.
It is sold as-is.
See picture gallery.
Video link will follow in next 24 hours.
Thanks for your interest.” Link
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