Friday, June 25, 2010

How to modify a Korg Monotron



So here's how to modify Korg's new Monotron analog ribbon synthesizer. Perhaps this is the first document of Monotron mods in Europe since it still hasn't been released here.

It's actually a very easy machine to modify because for whatever reason Korg decided to label all the interesting points on the bottom side of the PCB. This may well have been for testing units at the factory/service centers. Perhaps though it could have been that the designers anticipated this little machine would be hacked, much like the Gakken which pretty obviously inspired this piece. Incidentally in the magazine that comes with the Gakken there's a picture of them showing it to Korg, that was in 2008, go figure.

Modification wise everything is simple enough except for the gate. Unfortunately the gate point affects the pitch somewhat. There's a few solutions, the first of which is to use a single pitch cv line into the gate socket. This will work but you wont be able to get really low notes which is less than useful.

After a little research I came across an idea to use a dtc114 transistor to trigger the gate (soldered at a different point). I tried this but didn't have much success. Also that method will result in the LFO not re-triggering which is bad since the LFO is the closest thing to an envelope on the machine.

By far the simplest solution is to use something like Silent Way by Expert Sleepers (see my previous video on this software) or Volta by Motu. After calibration there's no issues whatsoever and the monotron tracks over 5 octaves nicely.

Using an adjustable dc power supply is a good alternative to the batteries and is also useful in getting the Monotron to a decent tuning range, just don't dial in more than 3 volts. I built my power supply based on this schematic

If you intend to use both battery power and dc power you should include some diodes in your design.

And lets not forget the filter, the side of the packaging says "the legendary MS-20 filter" while this is true design wise it would probably be more accurate to say the MS-10 filter since it's only low pass and the MS-20 has low and high pass filters. How does the filter sound? actually very good! I've repaired some MS units and the Monotron really does have some DNA from the MS series, even down to the small noise hiss when the resonance is high but not yet self oscillating.

A couple of things I noticed about the filter input, if you drive the input signal too hard the resonance almost disappears, so be sure not to overdrive it too much if you want the full character of the filter. Also the input jack is stereo which means if you use a Y cable you can run two signals into the filter comfortably. I tested to see if the left side input leaked to the right input and it doesn't at all, which means it really is a true stereo input to the filter which is very nice.

As for the output, even though it's a mono output via a stereo jack the manual states that you shouldn't use a mono jack on the stereo output, so it's probably best to use a stereo jack plug but leaving the ring floating to get a mono signal into your daw/mixer. The output is a little noisy due to the fact that its really a headphone out and the output level is a little low so you will probably want to use a noise gate to remove the noise floor when it's not playing. (this is the same with the Gakken)

That's about it, here's the diagrams for modding, as you can see it's very simple indeed and should be no problem for anyone with soldering skills.

The Monotron should be available to buy in Europe from around the 30th of June for around 50-60 euros.



95 comments:

  1. Could you run this mc-202 to mod to monotron then?

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  2. @ richardrich

    how do you mean cv/gate control? yes you could but tuning would be midrage, you wouldnt get any low notes and scale might be a little bit of an issue.

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  3. Wow, thanks for this. I just bought a Monotron today in Toronto, Canada, and I modded it tonight using your schematic. Then I downloaded Silent Way and got busy!

    I like your 4-pin DIN, but I can't help but think there might be something better. For now I just cut a small opening in the back of the Monotron's case and soldered the leads directly to the jack box with the resistors.

    It works beautifully, and the Monotron sounds really great. I'll probably put something on Youtube over the next few days, once I get used to Silent Way.

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  4. Thank you very much for your instructive work!

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  5. Thanks for this ! It opens new monotronic dimensions !

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  6. Absolutly excellent video - thanks.

    I am looking at building a Baby 10 with 555 trigger - shoud I want to drive the Monotron can I simply send the CV out from the Baby 10 - to the CV-Pitch input of the Montron? Do I need to worry about the CV voltge - I was planning on running it on a 9V battery ..

    Appreciate any guidance..

    s.

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  7. You'll need to measure the baby10 outputs and attenuate to suit, I wouldn't run more than 5v into the monotron tbh. Check my diy seq also here on the blog, it's based on the baby10

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  8. can you explain how to use something like silent way - do you calibrate the monotron or whatever is sending the signal? i don't think its an option for me either way.

    if i was to control this using the cv/gate from my x0xb0x would i not get the full note range?

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  9. Hi - I have got the Baby10 in production - and will use a simple voltage divider to ensure the actual CV levels only run from 0-5 volts.

    Looking at your schematics I am unsure how to take the single CV out from the Baby10 - and use it for CV/Gate - is the Gate just getting the same CV pulse signal to trigger the note ? Sorry if this seems a basic uestion - just want to fully understand what I am doing before I start hacking the Korg.

    Thanks, Stephen.

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  10. @derek

    silent way is a computer plug in, you can read about it here http://www.expert-sleepers.co.uk it uses your audio interface as a cv/gate converter and the calibration routine is part of the plugin.

    as for using the x0x, itll work but you may find teh tuning scale is wrong.

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  11. @ farmer glitch

    you can just use two resistors to attenuate the output, its quite simple, tie one to ground and the other inline.

    Yes you can use the cv line as a gate, use your cv line and plug it into the gate socket and dont use the gate line from your controller. If that doesnt work well you'll have to create a cv mixer to mix the cv and gate, which can be done very cheaply with an opamp and a few resistors (provided you have a bi-polar power supply)

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  12. Thanks for posting this howto,

    I've used your schematic to connect my monotron to an arduino.

    I am using a digital pin for gate and for pitch i'm using the PWM output.

    I have two problems at the moment:
    The gate is interracting with the pitch so some notes sound a bit odd.
    And tuning of the cv seems to be difficult too. Do you, perhaps, have some tips??

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  13. OK - think I get it- I guess I can simply take the 9 volt pulse from the 4017 of the Baby 10 - before I run it to the pot - and send that - shoud this also be 5 volts max - and I guess I'll need diodes on each pin too ?

    So I understand the top Jack input and bottom jack input of your scematic - are simply controlling the trigger and pitch - please can you clarify what the middle jack input is doing ?

    Many thanks again ..

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  14. Do you have a mouser part number for that 4 pin DIN, and the cable that would hook up to it?

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  15. Thanks for the video and schematic, works great!

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  16. I was hoping to use the monotron with a Kenton midi CV converter-gate is 5 volts on 0 volts off and CV is one volt per octave. Will the gate voltage be too high? There is an auxillary CV also on the Kenton which I hope to use for filter cutoff. Any suggestions from people? The monotron has a surprisingly nice and unique tone and it would be cool to control vibrato and "wah" from a midi keyboard via aftertouch and mod wheel. Looking at the photos of it's innards,the entry point of the ribbon to the board looks tantalizing for mod points don't you think,cos that could attend to gate and pitch from the one entry point? Or am I talking rubbish!
    Cheers Ross

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  17. is the CV volt/octave or linear like the MS-20?

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  18. Not to be too pedantic but 1v oct is linear, the ms20 is logarithmic. But in answer to your question, it's 1v oct

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  19. Quick question about the output:
    It's a stereo jack, but a mono output? How does that work? If you feed a stereo signal into the filter, does that mean it's summed back out as a mono output?

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  20. its a stereo jack output and it clearly states in the manual not to use a mono jack so i wouldn't recommend doing otherwise.

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  21. would it be ok to use a stand alone 3V DC power supply for this?

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  22. @ronan, probably but to be on the safe side make sure its a low ampage, 300ma or less and also that its a regulated power supply, it would be worth checking it on a meter since some supplys put out a lot more than what they are rated for. It would most definately be a better idea to build the power supply since you'll get a nice regulated and controllable suply then.

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  23. I'd like to do this mod, and it seems relatively easy. However, the CV output of my analogue sequencer (a Mochika 2.1) is in the form of a 1/4 jack, not DIN. So er... how would I go about this? Would a jack-to-DIN cable be sufficient to do the trick?

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  24. you dont need to worry about din, im just using that to connect the external box to the monotron, the external box is where you would connect your seq and you could just build that box with 1/4" instead of 1/8" jacks

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  25. What range of voltages can you feed into the CV inputs of the monotron? 0-3V, 0-5V or something else?

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  26. can you run through how you wired the din in relation to positive and ground terminals?

    also, i'm a little unclear as to whether the minijacks in the ext. box need to be grounded or not.

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  27. @Tonias 0-5v works fine

    @ronan

    its not really important whats wired where in teh din cable as long as the source and destinations match up. Ie, you wire the cv in to pin 1 and wire pin 1 to the cv in point on the board etc.

    And yes the mini jacks need to be grounded to the monotron ground else external signals wont work.

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  28. that's all clear but when using external power do i wire the negative dc wire to monotron ground also?

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  29. Hey Guys I just found this - http://www.fengland.org/mm.html
    If anyone was still having trouble with finding a MIDI solution ;]

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  30. @ronan yes the DC negative is wired to ground of course else theres no circuit ;)

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  31. it's my first build if you hadn't guessed, first of many hopefully. thanks! :)

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  32. cool, good luck its one of the more simpler mods

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  33. Wow, this is a great mod. I bought a monotron a couple months back and gotta say that for $60 odd bucks you're getting a great piece of synth. Gonna buy another and try your mod!

    If you're interested I've got a review of the monotron here: http://gamesounddesign.com/korg-monotron-hand-held-synth-for-sound-design.html

    Cheers!

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  34. hye i just bought myself a monotron...is the anyway that i can use it with my guitar and boss gt 10 efx?

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  35. Thank you for this great article. I'm about to get a Monotron (it's on its way from the US), and this video made me want it even more :)

    I don't see why you have to attenuate the output as you can supply a HCF4017BE (this is what I got) anywhere from 3V to 15V, and the output voltage is almost (0.05V less) equal to Vcc. Or am I just missimng something here? :)

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  36. @Anubus there's no 4017 in this mod, unless you are mixing it up with the step seq?

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  37. Yes, but didn't you say (in the comments here) you had to attenuate the output of your Baby10-clone sequencer to 0-5V so it matches the CV input of the Monotron?

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  38. ah well i did that since i use it with my modular and it make a lot more sense to have a 5v range there

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  39. I guess it was my fault to place the comment there :) But yeah, the 4017 works with 5V just fine.

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  40. Nice video!

    Is it possible to rig up the Monotron
    whit a Kenton Pro-SOLO MkII to get midi control and
    have them build in them to new case, and then feed
    them both with DC from this PSU unit

    (PSU data)

    Power supply with adjustable output voltage:
    0-12V. Max 5A. Input voltage 15V AC

    link to the psu unit (with picture)

    http://www.kjell.com/content/templates/shop_main_
    details.aspxitem=87184&path=&sms_ss=email&at_
    xt=4cc9c029cfbefe24,0

    Note! with this psu unit the device will need two
    of them, otherwise I can't feed the monotron and
    the kenton at the same time whit DC... not so
    convenient, but it works I think.

    if this works to together, is then possible with
    this setup to add more features (to add a full VCO section, full LFO section, full VCF section, full
    AMP evelope section, full Evelope 1&2 section +
    maybe add a patch feld to make it patcheble)

    to the monotron whitout changing the Psu or
    adding more of them?


    ///Daniel Fletcher of D a z z - S y n t h

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  41. @daniel that PSU will still require an ac/ac adaptor and its rather expensive (as i find most stuff at kjell is, cheap junk tbh) better to build a twin adjustable and run it from a single ac/dc adaptor then you can run two sources from it.

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  42. oh and for the kenton i dout you will get a usable pitch range (that'll be in tune) much better to use silent way or volta

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  43. Thank you so much for putting this up! I moded mine to work with my modular setup in one night! Such a blast.

    Thought I'd record some of the nastier things the Monotron can do and post it for people to check out if you're on the fence about picking one up:

    http://www.youtube.com/watch?v=0aJy1aQiAcU

    Cheers!

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  44. Hi 2cv et ALL,

    Clarification needed:
    1) because the Gate voltage affects pitch. I'm assuming that using a Kenton Solo Midi to CV adapter would limit the note range to whatever the Gate voltage is coming from the Kenton (5v gate)...soooo...
    2) Couldn't I wire inline a variable potentiometer to adjust the output voltage of the gate coming from the Kenton?. IE. trimming down the Gate voltage to 2 or 3 volts to allow for lower notes?
    3) you mentioned using a single CV line into the gate. Why isn't this a fix-all solution if a linear voltage was sent thru the CV line at 1v\OCt? I notice that the gate lower threshold is around 1.2v.
    4) Has anyone used another CV source successfully and had decent scaling? I am unhappy with Silent Way. The PC version needs many improvements and crashes Cubase 5.5 on my machine in an almost predictable pattern..
    5) I've been in contact with Forrest England, the creator of the Midi mod for this thing, and it seems that he's nipped all scaling issues with his mod. What can be integrated to the current CV schematic that would correct this issue?

    Thanks all for your input...

    Erik

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  45. @ Daniel Westin, any luck with Kenton...?

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  46. itll only go so far, its not just about the voltage but the tuning scale, with the kenton its 1v per octave, thats to say each additional volt will increae the pitch by an octave. This is why most 1volt/oct analog synths will have two trimmers internally, one for the base pitch and another for the scale. Such trimmers do not exist in the monotron.

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  47. @ Sablerock

    soory but I had'nt have the time to try this thing out yet, but me and my synth technician will try it out soon.

    I will tell you all about it, when we are done.

    Cheers!

    ///Daniel Fletcher of D a z z - S y n t h

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  48. Is where any one how have a suggestion on witch parts what I can use with the monotron?

    Im thinking about chips for a extra VCO's and a VCO part what can complete the build in VCO, and when a VCF part what can complete the VCF sektion, + Something for the LFO sektion, last but final a whole Amp envelope sektion + 2 ADSR Envelopes

    Is SEM chips a good choice, or is where something better?

    Cheers!

    ///Daniel Fletcher of D a z z - S y n t h

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  49. Hi Guys!

    I’ve started a Monotron forum. It’s a place where people can discuss Monotron mods, hacks, as well as other synths.

    Check it out: http://monotron.adornomedia.com/

    –David

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  50. Korg have posted the Montron schematics fyi...

    http://www.korg-datastorage.jp/Manual/monotron_sch.pdf

    =)

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  51. excellent find Ben, I'll take a look at doing a proper line out when i have time now instead of the crappy headphone out.

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  52. 4017 works from 3v to 18v so you can drive anything as long as you change the supply voltage accordingly :)

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  53. 2cv thanks so much, i bought a monotron just because of this!

    so i have been having a great time with the mod (here is a quick 3 x guitar-CV-monotron demo: http://www.megaupload.com/?d=Y8U7GKP5 )

    quick questions though in case you have the time:

    1. i noticed that if you send a pitch CV into the cutoff CV input, it tends to swoop in and out of range really quick (which is strange since the cutoff tracks across a more extended range when you just control the cutoff and the pitch at the same time with the switch)... do you happen to know what range of resistors/rheostat might do the trick to get the cutoff CV input to track a little more "broadly"?

    2. how hard is this 5V input CV rule? in my excitement, i tried the setup first with my theremin which puts out a 10V gate (it worked with no apparent damage, although the theremin sounds sort of lame with an on/off gate), and now my guitar setup uses an 8V gate... i've been playing for hours like this with no problems -yet-... do you think this is a bad idea?

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  54. i wouldnt drive it too hot, consider that its onyl really a battery operated unit so you might cook something. Somesort of attenuator would be a good idea for hot signals.

    when adding cv to the vcf dont forget that its only addign to the existing voltage set by the cutoff knob and the lfo intensity, setting them lower should yield better results.

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  55. thx for the reply!! you have convinced me to overcome laziness and open everything back up - i added a 330k resistor to the gate input and another 330k to the cutoff input - the math might not be quite right, but it seems to work great. (cutoff still needs a rheostat to get the filter tracking better, but it seems to be close)... thanks again for all of your help!

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  56. Hi Guys!

    I found something that is really good for this kind
    of thing this blog is about...

    I will use this device for my own Monotron
    "expansion modul" prodject that I have started
    up with an pro synth engineer...

    what I found, is device the gives your montron power (psu power) + it also gives you a CV/MIDI interfac
    at the same time.

    and the good thing about it is that, it only coast's 79:- euro

    + with this device you can also add extra futures to your monotron lika a VCA, or a ENV gen etc. you
    chould even get a full VCO or VCF/LFO. With this
    device you can add up to 8 diffrent modules of euroracks to it...

    In theory with this device you could make a monster synth with the montoron as the main sound engine...

    where is only one expression that can explain this:

    "This is way to cool for school"


    here is a link to the device.

    http://www.mfberlin.de/Produkte/Module/Power/POWERe/powere.html


    Cheers!


    ///Daniel Fletcher of D a z z - S y n t h

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  57. hi Danuiel, yes those are great, i use two of them in my modular, MFB also sell 3u frame for this which is compatable to eurorack modules.

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  58. Hi 2cv,
    I'm having some problems calibrating my monotron with silent way. Could you possibly export your silent way calibration file and place it somewhere for us to download? I'm just interested to see if using your calibration template will result in some usable tones for me.
    thanks!

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  59. really busy over the next few days but i'll see what i can do over the weekend or early next week, remind me if i forget ;-)

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  60. Hello all. How will you fix the audio out on the monotron? Is there a schematic (general) to adapt to fixing the headphone output?
    I'd love to run other audio through this little machine for recording, as the filter really brightens and fattens things up.

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  61. So I successfully de-linked the gate from the pitch CV by removing one of those tiny resistors... basically if you are "pretty competent" with SMD soldering you can just follow these instructions (see the section entitled "at first"):
    http://beatnic.jp/monotron/midi-kit.html

    if you are only "marginally competent", you will do what i did and accidentally disconnect the gate CV pad from everything and the monotron amp will just stay "on" regardless of input... a workaround is to run a wire to bring the gate CV input directly to the big IC (see the schematic, if i recall pin 10?).

    although the built-in keyboard strip will not trigger the gate after this, the gate CV input will properly trigger both the amp and LFO. and the tiny keyboard will still affect pitch if something else is triggering gate.

    finally, although i posted earlier i was using a 330k resistor to lesssen my gate CV, i am finding that, if you are like me and using an analogue systems envelope follower to generate the gate CV, you need A LOT more resistance to cut the signal to workable voltage range.

    has anybody gotten a clean signal out of the monotron? i read from somewhere that you can avoid the noise by connecting to the middle pin of the volume pot, but in my quick experimentation i didn't have any luck with that...

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  62. @ Jeff , I calibrated my monotron with silent way and got a usable range of 4 octaves with a behringer uca202 soundcard. Just copy/paste this in a *.txt file and it should work:

    Silent Way Calibration Data
    version: 1
    42 0.34889168
    43 0.40106520
    44 0.43328676
    45 0.46550831
    46 0.49772987
    47 0.51377177
    48 0.52858740
    49 0.54340303
    50 0.55821866
    51 0.57303429
    52 0.58784986
    53 0.60266548
    54 0.61748111
    55 0.63008136
    56 0.64039880
    57 0.65071619
    58 0.66103363
    59 0.67135102
    60 0.68166846
    61 0.69198585
    62 0.70230329
    63 0.71262074
    64 0.72293812
    65 0.73325557
    66 0.74357295
    67 0.75323087
    68 0.76179922
    69 0.77036750
    70 0.77893585
    71 0.78750420
    72 0.79607248
    73 0.80464083
    74 0.81320918
    75 0.82177746
    76 0.83034581
    77 0.83891416
    78 0.84748250
    79 0.85605079
    80 0.86461914
    81 0.87318748
    82 0.88102514
    83 0.88866681
    84 0.89630842
    85 0.90395010
    86 0.91159177
    87 0.91923338
    88 0.92687505
    89 0.93451667
    90 0.94215834
    91 0.94979995
    92 0.95744163
    93 0.96508330
    94 0.97272491
    95 0.98036659
    96 0.98800820
    97 0.99564987

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  63. @2Cv

    Does the the MFB psu/Midi to CV unit comes whit pre programed midi part or do I need to program the midi part my self?

    ///Daniel Fletcher of D a z z - S y n t h
    www.myspace.com/dazzsynth

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  64. Hi youp, thanks for the post i will try this, because me too having hard time to do calibration, i always get saw or sine wave type. I've checked the voltage with my multi, the voltage indicate for exemple : if i'm test only the gate cv line alone with nothin else pluged i read 4 volt, as soon as i put another cv line lets say vcf cv line 10 volt, the voltage go reverse into the gate cv line and my reading give me also 10 volt or so in the gate cv line, is it the monotron gate problem or i did a bad soldering on the pcb ??

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  65. I'm new to synths, so I don't actually intend to modify my monotron, but I wanted to find out what you meant about overdriving the filter. How do I avoid overdriving? Is input from my computer's sound card going to be too much for the monotron's filter to handle without damage?

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  66. @Hazel

    what i mean by overdriving is sending a signal that is too loud.

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  67. @2Cv

    So basically, as long as I keep the volume of whatever device is outputting the signal fairly low, the filter should be fine?

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  68. you also dont want to drive it too low to keep the noise level down, best to experiment and see how far you can push it, I found that if the signal was too high the resonance disapeared.

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  69. Hi,
    how can I get rid of the noise on the monotron?
    Is there a way to improve S/N?
    Does it help to skip the voltage coverter 3V/5V and to apply a yet higher voltage to the circuit. Anyone tried?

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  70. does this mod allow for the proper retriggering of lfo when it receives gate?

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  71. yes lfo is retriggered with each gate sent

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  72. @ ipc.de
    The noise seems to be from the filter circuit.
    Check this thread for more info.
    http://www.muffwiggler.com/forum/viewtopic.php?t=26319&postdays=0&postorder=asc&start=0

    ReplyDelete
  73. Hey, can anyone suggest what's happening here? :
    I'm endeavoring to get the monotron working with my Kenton pro2000mkii and with it set to volts\oct it seems to be moving the monotron in the wrong direction -- ie higher note from kenton = lower pitch on monotron. any ideas??

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  74. -Runs to maplins to destroy my montotron!- I was getting a bit fed up of the sound now this I can work with! I could use one of my monotron's midi sequencers with a bit of work to add a new external machine! wooohoo!

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  75. what about the other labeled points on the board? is there anything useful i can do with them?

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  76. and could you post a pictures of the inside of the breakout box? i cant figure out what i'm doing wrong...

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  77. Hey Nice video.

    I'm gonna use:
    1) a photocell and 3v on Cutoff
    2) a photocell and 0,7v on Rate(Lfo)(for precicer control)

    Can u please tell me howmuch Ampère I need for rate and cutoff?

    Would be really helpfull.

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  78. Anyone mod the VCO pad yet? I've not seen any mod tap off this line and I'm not clear if it's the raw VCO output or VCO 'input' hope it's the latter.

    ReplyDelete
  79. @ youp / 2CV

    Hey, to get a Behringer UCA202 or similar interface working with Silent Way, do you have to use AC Encoder with some modified cables?

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  80. hi my monotron only works with a mono output. could you clarify why this may be ?

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  81. Sorry to resurrect this but I've got the same problem as James posted last year. Namely, the higher the note I play on my MIDI keyboard, the lower the pitch of the monotron. My MIDI-CV is definitely outputting 1v/oct as normal. I'm tearing my hair out - any ideas?

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  82. Hi, sorry to bother with what could be a stupid question, but using the gate and cv out of my doepfer Dark Energy I can control the gate, but the pitch and the cutoff do not work. I can control the pitch with the LFO of the dark energy but not through the pitch jack,only through the cutoff. Any ideas? please help

    ReplyDelete
  83. sorry everyone for not replying on teh many questions here, not had time and it feels like such a long time ago that i did this :)

    @James

    iirc the gate affects the pitch, so perhaps your gate is too hot.

    @Aaron sorry, id rather not take it apart now ;) the schematic shows everything.

    @brammeown not much, certainly in the low ma area

    @Trevor Nunes it might be the raw vco, cant remember sorry.

    @Charlie Kemp thats a question for the silent way forums i think ;-)

    @soulvent its mono yes but you should use a stereo output according to the manual.

    @robman84 i suspect the gate signal is too hot

    @Plaxid are you using cv1 on the rear of the dark energy?

    ReplyDelete
    Replies
    1. Yes I am. The CV1 as pitch output too

      Delete
  84. thanks for the 'how to'
    it works great triggering from my SH101
    I don't really understand what I did but it's fun
    I can't play well tempered scales from that Cv in Monotron stuff but the 303 effect is here
    someone may leave an answer, please, if there is something I can do to get more precise octaves and other intervals
    thx

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  85. Help!..I did the mod (Gate and pitch cv only). I'm triggering using a PAIA Fatman but there is no change at all in the notes if I play in my keyboard lets say a do..re..mi...in the PAIA you hear a do..re..mi...but in the korg I only hear a fa..fa..fa..any comment will be more than appreciate it...Thanks in advance..Sid

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  86. Hi!
    I've build the GATE IN circuit replacing the on-board SMD resistor that connects the ribbon with gate input with a diode, adding one also on my input.
    There are no problems with pitch and the frequencies go nicely low.
    some rough, rough pics:
    http://www.teck.niezba.org/?s=objekt&o=016_-_K-mono_prototype&c=red

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  87. Hi! I've built a Midi Master Clock, that sends sync24 as well. How should I wire it up to Monotron in order to have a synced LFO?

    http://gieskes.nl/master-clock-generator/images/sync24-Schematics.gif

    My guess would've been: start/stop to the LFO, Clock to RATE, and ground obviously to GROUND. Is this correct?

    Regards,
    Asko

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  88. I've never done a mod on anything before, but it really looks like my monotron will be capable of some good stuff if I do it. Would this be a possibility for someone who has never tried messing around with a PCB?

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  89. Hi there!

    Thanks for this.
    I'm currently doing this mod and I'm not quite sure what the 10K pot is doing. It doesn't make any difference whether or not it's on the breadboard (testing stage still!). I've tried different values...nothing.

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  90. Hello!
    I was thinking about using the Monotron as a filter for a Atomosynth Mochika (Stepseq/Synth). Is there a way to mod the Monotrons LFO to sync up to the Mochika? It has Gate/Clock and CV outs. Any ideas?
    Thank you fine people in advance :)

    ReplyDelete