Yamaha QY10

<a href="http://burnkit2600.bandcamp.com/album/digital-drum-destruction-derby-demos-vol-i-yamaha-qy-10">saturated dnb by Burnkit2600</a>

QY-10 stock stock photo from wiki
This tiny synth/sequencer’s biggest claim to fame was it’s portability. Basically, it’s got 30 pre-GM instruments and one drum kit with 26 sounds, some of which aren’t all that bad. It’s sequencer is handy too. You can read more about this “walkstation” here.

I thought I’d open it up and see what I can see. After poking around for a bit, it was clear that many interesting features are hibernating on this little device. Here it is jacked up on my workbench, many wires for the bends are already in place. I used an experimenters board for wire management:

(Click pic for a close-up of board)
QY-10 brain surgery..brain surgery..
There’s tons of good circuit-bends in this little box. It’s all very small though, so it’s sort of an advanced project, but definitely worth the work.
After deciding which bends to keep, I would need to build a breakout box that’s larger than the unit itself, so I just recased the whole thing. I made a new control panel out of plexi-glass and mounted the QY10 right to it.
Here’s the rear of the panel, QY10 faceplate mounted to the front, main PCB underneath, switches, LEDs, & pots are all in place and wired up, just need to connect the main PCB wires that are hanging loose to all the new controls.
qy10 panel chaos

I recased the works in a small suitcase.
qy10 complete order
3 output jacks and the midi hardware are mounted at the rear of the case.
The switch matrix works sort of like a patchbay which allows for easily creating large numbers of multiple bend combinations. Each switch has 2 LEDs to indicate status.
The right side of the case has the volume controls, 3rd output audio source selector, 2 distortions, sound scrambling controls and ground-bend amount.
I used detachable hinges on the upper half of the case so it can stand alone as a table-top synth or be it’s own carrying case with room for the power supply and whatever wires I might need.
qy10 recased
I will eventually put a battery pack, an amp and some speakers in the upper half of the case and maybe a Highly Liquid relay kit too to trigger other toyz and make this QY10 the ultimate portable groovebox.

IC4 or 5 is the voicing chip for the QY10 (anyone know for sure?), I soldered all my wires to connections on these 2 chips, but mainly to IC4 as access to these was easiest. Messing with some pins will cause it to crash and some others will wipe the memory clean, but it’s a pretty robust chip, I haven’t blown it up yet.
Stick to these notes and you and your QY will be fine.
QY-10 medullaIC4 = sleeping giant

The switch matrix:
On IC4, pins 27-36, and 38-53 can be directly connected in any combination (I’ve found so far) without crashing and can also be connected to ground.

Pin 37 can be connected to the above pin numbers, some of the pins will create really cool stacatto notes (short blips). Don’t connect this pin to ground, it will crash. below in forum post #63, arsenlives experienced a fatal perma-bending crash with pin 37. Until we have definitive information, I suggest avoiding this pin altogether.

Sound scrambling mode:
Connect pin 14 to ground. I control amount with a 100k pot for coarse tuning in series with a 1k pot for fine tuning.

Connect either pin 28 or 29 to ground. I used a switch to select between them and 2 1k pots in series for amount.

Volume Boost:
Resistors near the volume slider on the board limit the volume of your QY10! Get a serious boost in your output by simply bypassing R10 and R17 or replace them with smaller value resistors.

Sound Samples:
drum & bassy groove
sweet and sour
(mp3)Bonus beats
just qy10 drums and bends

Check out how to replace the internal battery in your QY10, here.

The very brave Concretedog has become the first to attempt my mods.
Check out his QY10 here.

Concretedog's QY-10

Ian Brown went nuts with his mod job, tons of controls on his attached control box and look at that breakout box!
Ian Brown's QY-10
Ian Brown's QY-10
Ian Brown's QY-10


    I bought an ued qy-10 anf tested it….
    Maybe u need talen to….

  • zx81.. just checked out your page of QY-10 tracks.. you’ve got talent man. thats fun stuff. I’ll be updating this page with bending tips soon enough, check back with us.

  • I recently bent a Yamaha MU5. My next project is going to be QY10. I was trolling the web looking for information to see if anyone else had attempted this unit and stumbled upon your site.

    Have you gotten any further with the mods? Willing to post an points you found especially interesting?

    I’m going to begin working on mine soon.

  • Well, I’m right in the middle of the ambitious process of recasing the whole machine, so im not ready to discuss the specifics of the bends at the moment. If you look at the pics above, you can see where i’ve been working. All the bends are on that one chip. Connect points to each other or ground.
    If you’ve bent an MU5, then you’ve probably got a headstart to where I began with the QY10. I’d like to hear more about what you’ve done with that one.

    Updated the main post with a progress report.

  • can we see some new case pics.
    dont know if this has any tap input button so you can tap in beats, if not you could rig a couple together using piezo`s and attatch to the internal sample trigger inputs if you have found them.mpc like.
    cheers ,glenn.

  • Cool idea, but the QY10 has a mini-keyboard controller on it, and I’m keeping that – so I won’t need to worry about triggering that way. Plus, seeing as it’s MIDI capable (though primitive), I’ll mostly be sequencing it externally.

  • I don’t know if you can help but I have a QY20 that started to show
    “Internal Battery Low” message and I would like to replace the battery
    without having to send it back to Yamaha.

    Do you or anyone you know have details on how to do this ?

  • I haven’t messed with a QY20 yet, but assuming the layout is similar to the QY10, you’ll see two circuit boards. Here’s the lower QY-10 PCB, the battery is the copper cylinder near the switch on the left. The QY20 *may* have a flat silver disc type battery instead. Internal batteries are generally NiCd sometimes Li, about 3V, and are clipped or soldered right to the circuit board.
    I didn’t need to replace the qy10 battery yet, so just guessing- I *think* it was just clipped in and with a little force or bending back a post, it can be coaxed out carefully. Though it may be that a small amount of solder is holding it in, in which case you will have to get your soldering gun and carefully heat the posts and pluck the battery out. The battery should be imprinted with the type and voltage on it. Get a new one from radiosmack or wherever and reverse the whole process.
    If this is beyond you or if your QY is somehow still under warranty, don’t attempt this, send it to serviced.
    Whatever you do, be sure to back up your data first. If anyone has specific details about battery replacement for the QY10 or QY20 feel free to drop it in here.

  • Hey, can we hear some more sounds from this thing? I’m very much liking the one already up, and i’m just off out to see if my local pawn shop still has the QY I saw in a few weeks ago!

  • Hey Jacien, next time i’ve got it plugged in I’ll grab some noises for ya and post ‘em. If you can get one on the cheap, grab it!
    [Edit: new jamz uploaded.. enjoy]

  • Battery ?
    I Bought a 2d hand qy10 lately and I´m very pleased with it. Connected to a Korg synth, it does a great stuff. Now the left cursor only works 20 seconds after switching the sequencer on, and then doesn´t work anymore. Has anyone had such a trouble ? Do you think I must replace the internal battery ? Thanks for yr help !

  • Hey Emmanuel,
    The internal battery backs up sequences mainly, but if it becomes corrupt and leaks, it could make the whole system inoperable. This happened with a Yamaha drum machine of mine. I cleaned it up & replaced the battery- problem solved.
    But before you open it up, you can check these things –
    After the screen goes blank, can you still get sound out of it? If so- then it’s probably the lcd screen itself, or a connection to it.
    Also, are you using fresh batteries or the AC jack? -Try both these means of power, it could be a bad power terminal.
    If it still won’t fire up- then take it apart and check out the battery. A couple messages up from here, I talk about internal battery replacement, check it out.
    The battery is a small copperish cylinder, and will probably have to be special ordered, Ian (from the message above) got one from Yamaha’s UK support staff for about £10. Let me know how it goes.

  • While on the subject though, there’s probably no reason you can’t replace the non-standard battery with a different type one as long as it’s the same voltage.

  • I replaced a dead battery in my q10 with a couple of leads to a 3/4″ diameter watch battery, it fits neatly into the casing. Make sure you solder a small capacitor… say 100uF parallel to the new battery if you are using a substitute or you will suffer memory loss after 10 mins or so of switching it off.

  • There ya go.. Those flat-disc batteries are much easier to find. thanks for the tip Mahoney.

  • Well, my old QY20 it´s waiting for backup battery replacement aswell. I also thought about using a couple of small buttons, but i´m quite confused now about the thing of the capacitator, and the consecuences of not doing it that way.Could someone clear that fact a bit please, and by the way comment if there´s a risk of total deletion from data inside the QY by interrupting the backup battery power ?

  • I can only go from my experience with my qy10… I’m not 100% as to why the memory will not hold without the cap in parallel to the battery, maybe the device draws a sudden spike in current which the replacement battery can not provide itself, but it’s not likely… I could send you a photo of the way I did mine, I’m not sure how similar the qy10 is to the 20.
    You could clip on an alligator lead to each of the battery connectors in your qy and attach the other ends to second battery to retain the memory while you desolder the original battery and solder another in its place.

  • Wow, I almost put away the cell for using it as sample while going around in search of a replacement. That would have surely been the end of the QY, with no further full reset chance(glups!),isn´t it so?
    A couple of years ago I found a shop where to replace the ten years old original battery, and it went fine with the new one untill last week. I looked inside, and found the solded cell quite rusty (MMMM?), being impossible to read any information of brand, model,or voltage.I won´t pay 30$ for such a mess this time, so I´ll do it myself, but calmly taking time for finding the most suitable battery in town. Thanks a lot for the advices, Mahoney. The QY20 is an old tripping mate,truly dear to me. It´s great i´ve found this place.

  • Either of you ever try a midi dump? That’d be the most reliable backup.
    Hi Gom- Get that corroded battery out of there soon, you don’t want it to infect other components.
    Mahoney- if you want, send a clear photo or 2 to us and we’ll post ‘em up here.

  • Aha! I found it: Ucar 2L76.

  • Thanks for the info Gom, i’ll put it in the new battery replacement post.
    A quick search shows that its a 3V Lithium battery.
    Ucar 2L76 equivalents are Duracell DL 1/3N, Kodak K 58L, Philips CR 1/3/N, & Varta CR 1/3 N.
    Additionally, you should be able to stack 2 1.5V of the smaller watch-type batteries in that clip- those are pretty easy to find.
    -More options than I thought.

  • Hey there QY Wizards, maybe someone of you can help me out. I’ve had two QY10s so far (one sold to a Friend now), and they both had a problem with the changing of Instruments in Patterns. Everytime I make a Pattern, then change to another one and go back to the first one, the Voices are Reset to a default setting while my sequence is still there. I’ve read the manual several times to find out what’s going on, but didn’t find anything at all. Any Ideas? Do you think this could be a Battery Issue, too, or is this something else I should know about?

  • I’ve noticed this once or twice myself, though i’ve never detected a real pattern as to say it’s definitely one thing or another. Of course i have to consider that any buggy behavior i see in my machine could be due to the fact that it’s bent and modifed to within an inch of its life. But it could be a bug in its ancient OS. Is this happening just in pattern mode or in song mode?
    Either way, I do most of my sequencing with an mpc2000, and i always embed voice selection and mixer settings in each mpc sequence using midi control change numbers that get sent to the QY10 at the beginning of each sequence.
    i’ve never tried recording these changes in to the actual QY10 sequencer, so I’m not sure that it is possible, but it’s worth a shot.

  • der Warst it could be as simple as going to menu > utl > str. when you change to a different song for some reason if you don’t store the set voices they will reset. that oculd be the problem.

  • Thank’s, I’ll try that.

    ahem… Btw: my URL has changed, could you please update that?

  • your previous post url? umm. . sure. done.
    Did Paul’s suggestion work for you?

  • g’day
    all this talk of qy10s and 20s, i was wondering if anyone has bent a yamaha su10 sampler? any info on bending said said sampler would be greatly appreciated.

  • far as i know, no one’s bent any of the yamaha sampler line.
    should be possible though.. i have the su10′s grandkid- the su200. don’t really use it much, so i’ve been thinkin about bending that.
    we’ll see . .

  • Hi guys, I’m interested on buying a QY-20, I was wondering if any of you can post MP3 samples to hear it. I heard the QY-10 samples posted on this page, but they are distorted! :)

  • distorted? sure they are.. thats what we do here.
    i dont have a qy-20.

  • Someone else might, thanks anyway.

    Oh, I’ve been hearing your Atari 2600 song cartridge! It rocks! I find it interesting the mods/bends you do. I didn’t know there was a scene about this. Great stuff.

  • Thanks and welcome to ‘the scene.’
    I’m guessing you’ve found us through someone’s ebay auction. If that’s the case email the seller for some straight audio.

  • Hello.
    Apolofgies for the intrusion but I would REALLY appreciate if you could send me a message explaining very plainly how to do some BASIC drum recording with this Q10 to use as a click for my drum session work. Basically I would need it to build my own Clicks in different time signatures etc but mainly 4/4. I loved the idea of having this piece of kit as it is very very small indeed. I was gifted with it a while ago but I really do not have a clue on how to read the manual -which I have- but it really is very difficult…well I am a bit lost really ! I hope that you can help with some basic sequencing programing so I can get to really use it. Any help would be Greatly appreciated! Many thanks indeed.

  • Carlo, check out the manual.

  • it could be as simple as going to menu > utl > str.
    Yeah, it actually was that easy. I kind of feel like an idiot now for not finding this for about 4+ years…

    Thom, I found out that you seem to be not quite correct in your description, because I’m pretty shure that IC5 is the sound Rom. But then all of the pins of IC4 you stated valid for bends are actually pins that connect to IC5, so there isn’t much of a difference whether you take this one or that one. And it’s SMT, too, so there is little to no improvement apart from not having to count the pins according to your description when using IC5.
    I’ll post some documentation about my stuff soon.
    cheers, der Warst

  • Theres got to be a few other hidden features in there as well besides ‘store.’
    I pretty much use only my MPC for sequencing at this point, so sounds and sequences are stored on disk.
    I noticed the connections to IC5 as well & im no expert on Yamaha chip sets, so i made some guesses.
    There’s probably other bad info & advice on this page as well :), i’d love to see the service manual and schematics for it at some point.. anyone got it?
    Btw I’m so glad to see someone else has stepped up to mod this little guy. Do keep me filled in!

  • The big problem is that about all the features are “hidden” in the QY10. But if you take the time to dig into it, it really starts to shine.
    I’m not very much of an expert, too and I’m pretty sure Yamaha uses custom roms, so you won’t get very far with a mere Datasheet googling. But then again, rom chips most of the time look pretty much the same (at least in Dip or Sop housings). They usually have about 28-32 pins and about all of these Pins are connected to a controller (bigger chip) somewhere else on the board.

    Right now since I’m doing my Diploma in Arts (it’s sort of like a German variant of master), I have a very nice Lab built up at my university and last night my girlfriend came by and I gave her the QY10 so she won’t get bored while watching me working and she instantly was drooling on it for hours and hours. And she only used those crappy preset sequences and still it didn’t get boring.

  • Yea, if the QY-10 is filled with anything, its instant gratification.

  • Crazy, I never would have thought of bending my QY10. After checking this out though, I may have a future project…

  • it’s worth the work. its become an essential part of my setup.
    id like to see you recase it in a huge box like your 505 ;)!

  • I do have another PC case exactly like the one I used for the 505, but I think I’m gonna save that one for a custom midi controller. I really like the portability of the QY10, and obviously that would go out the window with a pc case like that. I do like the suitcase idea, but now I’d have to come up with something original since that’s already been done with yours.

  • i hear ya. keep me filled in with what you end up doin’ though.

  • alright guys? great website you have here! i’ve been bending drum machines and NES consoles for live sets for a number of years now, but this QY10 looks the absolute nuts! well done, and thanks for posting up some tips on bending it.
    one question though, i take it that the pots you’ve used are just ordinary “audio trim” type pots, or is something else more suitable required?



  • bod, actually i mostly use linear tapered potentiometers. i’ve got a decent stock of them. Usually, if I don’t specify the pot type as audio tapered, it’s linear. I try to keep these tutorials open ended for ya’ll to experiment with your own control interfaces a bit.
    Send some photos of your QY when its done.

  • cheers Thom. just bought a big bag of mixed pots from maplin here in the uk. was only £5 for 20 different types that they obviously cant sell, but gives me plenty to play with!
    thanks for the advice though. :o)

  • hi
    i bought a yamaha qy20 a while back secondhand

    when i turn it on a line appears on the lcd momentarily then nothing
    a line also appears in the lcd when i turn it off

    the voltage across the internal battery is 2.6volts

    any idea whan i could check to try get this working?

  • voltage across the internal battery was actually 0.26volts

    would a low internal battery cause this kind of malfunction?

  • yea, most likely the battery. also check the connections from the ribbon cable for the lcd board. did you ever get this qy lcd to work normally?

  • LCD never worked normally
    it was like this when i bought it
    it was being sold as a nonfunctioning item

    i checked the ribbon cables already

    will try the battery when i get another 3v


  • nonfunctioning eh? does it make any sound?
    you can test if its the battery by temporarily (and carefully) hooking up 2 1.5V batteries, like AA, AAA watch batteries etc.

  • so i tried this over the weekend
    i got a 3v battery , it was one with solder tags so i put it over the battery that was already there.kinda piggybacked it

    tried turning it on and it did the same thing
    a brief filck on the LCD then nothing

    any other suggestions before i give up on it?


  • Well, seeing as you went and got a new battery, I would go ahead and replace it properly. Then get a pattern running and let it play for a while. Check it after several minutes when its warmed up.
    When my screen is acting up, which is happening more often now, it usually comes on after a few minutes with garbage data, then a second power off/on fixes it.

  • Hi i have an QY-20 and from one day to another no sound is playing by the phone or line output .Midi out is working on externe sound module.All other functions are normal.I am an electronicus and maybye you can give me some tips for localizing the fault.Is it the soundchip or an audio fault?
    Do you have firmware or schema?
    I wil thank you in advance
    From Belgium
    Luc Zeeuws

  • I am not that familiar with the QY20, but I would start by checking that the sounds are not muted within the QY20. Then I’d check the hardware: is the output jack broken or has the solder come loose? Is the Volume pot broke? It’s most likely one of these simple issues.
    What’s an electronicus? It sounds like a pretty cool title.

  • nice work with the qy, tho i dont think i could do tiz bends to my baby. i use it as it’s intended (portable midi) and to sequence my roland sp808. peace.

  • I’ve purchase an second hand qy20, when i turn on, is ok after 2-3 min. the left channel begin to make noise and make lot of disturb, I clean the volume contact and check for solder loose, what you think you can help me? (xcuse for my english)

  • Hard to say what the problem could be for certain from your description.
    Make sure you are using the correct power supply, and replace your internal battery. That would be the place to start.

  • Hello,
    I have a QY20 and I have a same problem as Rob. It has work properly when I bought it. And after it has go wrong. “When i turn it on a line appears on the lcd momentarily then nothing
    a line also appears in the lcd when i turn it off”
    If I adjust the contrast the LCD shows anythink but very very faint.
    Have anybody a schematic for QY20? I try to repair it and I think negative supply is not enough for driving LCD contrast but I don’t know how create negative supply from +9V. If the LCD power supply is 5V the driving voltage must be min. -8V. Have anybody an idea?
    Thanks in advnace,
    Tamas from Hungary.

  • hi there my qy 20 which until now worked fine no longer powers up….any ideas? could it be the internal battery?

  • Hey guys, sorry for the lack of answers. Though this forum is mainly about finding new ways to break things, I’d like to think we can fix things too. It’s hard to fix stuff via the net.
    To both of you I’d suggest checking all your solder points around the power input jack, double checking the ribbon cable connections, and consider a new internal battery and/or power supply.

  • I canNOT believe the kick drum in your bonus beats sample! It makes me want to go back in time and not sell my QY10

  • Heh. I’ve taken to calling it the ‘brown note’ in my drum arsenal.
    It’s known to loosen things.

  • ive been bending a qy10 and i came across an odd problem. one of my bends (actually pin 37 to 37 on ic4) is now permanently on. i think it got hit with a small amount of voltage and now doesnt want to turn off. all other functions are normal. im wondering if there is a way to reload the firmware on the chip to see if that would sort out the glitch, perhaps detach the internal battery would do kind of a reset? ive checked all of the connections on ic4 and they seem to be okay, nothing shorting. i ended up connecting all of the bends to a 25pin dsub so nothing should be shorting if the connector is unplugged. any ideas?

  • The firmware chip is most likely a “burn-once” rom. And I doubt it is easily replacable. Printer cables have been known to be faulty sometimes. I’ve heard people complain of “cross-talk” between wires, etc. You could try disconnecting the internal battery (you will lose any user data), and discharging capacitors. If that doesn’t work, you may want to disconnect that 25pin cable.

  • after much voltmeter probing it seems that my poor qy10 is toast. sometime shortly (maybe half hour) after the permabend happened the board just shut off and wont come back to life. tried many things to revive it but it seems that this one is a goner. thanks for the help. looks like the breakout box is gonna have to go on another, more alive, qy10.
    ps beware of pin 37

  • Hi, I have a problem with the qy-8, http://www.youtube.com/watch?v=FQxKvd3O8A0

    I get a beeping noise that won’t stop until I change styles, it is only supposed to be a clicking sound, but it a very high pitched annoying beep. I’m wondering if anyone who has circuit bent something similar knows which connection causes this clicking noise, and if it is separate from the noise generator. Could it possibly be that I need to replace the battery?

  • Beautiful work! However, I haven’t seen much /addressing the knob controls….

  • I’m pretty sure this part is describing the knobs:
    The right side of the case has the volume controls, 3rd output audio source selector, 2 distortions, sound scrambling controls and ground-bend amount.

  • arsenlives, sorry to hear about your QY10. did you try pulling out the internal battery, and discharging all capacitors in their? It’s worth a shot. Also, check for shorts in your db25 connector, cables etc. I’ll put a note in the info above to avoid pin 37 altogether if you think that was the culprit.

    Mils, sometimes my qy10s drums do the same thing. I change modes and it works again. That beep is unusual. Could be a problem in its software. I hope you can overcome it. I’d try replacing the internal battery and make sure to use the right power supply.

    Shaun/Sam: Yea. My controls are described like Sam sez.

  • Has any circuit bent it’s big brother, the qy20? I just picked one up…

  • Hi, great site. I’m a musician and electronic tech out of Minneapolis – I intend on modifying my own QY10 in pretty short order.
    I attempted to secure the service lit for this device from Yamaha and they blew me off with a link to their drum hardware catalog!
    Regardless of my ignorance of the chip pinouts, I’m going forward w/ experimentation based on the info here and @ concretedog.

  • Mod is just about done – 36 momentary switches, 2 rotary switches, 1 potentiometer, encased in a cigar box that shares space with a 1X4 MIDI thru device. Documentation forthcoming if there is any interest shown.

    If I come across a QY20 I’ll grab the service lit and go to town – seems like there has been significant enough interest.

  • Hi Shiny, Great to have a ‘real’ tech weighing in on this device. I welcome any info you’d like to contribute for the good of mankind. Send some text, sounds and pics – we’ll host all the goods.

  • Novation released a midi keyboard specifically for the qy10-the novation mm10-they are pretty neat, an unbent qy10 can sit in a wedge/cradle that is cut out of the top, sits in at an angle a qy8 also fits in it.

    It has a snake wire that is a midi cable, power cable and audio cable all in one that hooks up the two machines together so you only need i power adaptor and you get 1 octave of full size keyboard with velocity.

    I’m using my spare unbent qy to write on and then gonna midi it over to my other. The wee keyboard on the qy can be abit basic.

  • novation is a 2 octave keyboard sorry, it also has pitch and modulation wheels, wikipedia has a good photo of qy10 slotted into mm10…..

  • Anybody bent an su10 yet? i have the service manual and am considering bending and any other mods i can figure out. already opened it up. there is no room at all inside! not even for one 1/4″ out jack. i like making breakout boxes anyway.
    bueller ?

  • @meech – wondering if you delved into the unknown and bent your SU10?

  • I just put a QY10 on eBay.de today. Good working order.

    It´s in German.

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