Yamaha DD-14 with patch bay

phantompowers · January 17, 2011, 03:14:28 PM

I've just finished bending this machine and it is awesome!! It was a relatively easy bend as well.
To save money I made the patch bay out of nails. I figured this had to be the cheapest way of doing it and I'm a right cheapskate.
There are 3 main chips on the board. The only one I have used is the one named 'MOSEL'. Each nail is wired to one leg of the chip.

Doing it like this also enables you to still view the presets.

After removing the speaker I glued a piece of wood in the cavity to give the nails a bit more stability. Then after drilling all the holes I hot glued all the nails in place. This turned out to be a bit of a nightmare because to get the solder to stick to the nails they had to get really hot. This kept melting the glue.

All 32 legs and nails wired together. I ran out of decent cable half way through and had to finish the job with old speaker wire.

Now please enjoy my demo vid!

Circuit Bent Yamaha DD-14

On the vid I am just randomly joining patches and working my way through the 100 preset rhythms.

phantompowers · January 17, 2011, 10:43:26 PM

I hadn't fitted the case back together when I made the vid. And earlier today I tried to. Guess what? Like a total dick I hadn't taken into consideration one of the main screw supports and it wouldn't bloody shut! I had to snap it off with my pliers and put a sticker on the case where the hole is.

phantompowers · January 18, 2011, 09:21:36 AM

Also, after messing about considerably with all the connections on the patch bay I can confirm that the only pins you need to avoid are 1 and 32. All the other points can be joined in any combination you wish.

Circuitbenders · January 18, 2011, 12:29:49 PM

lovely stuff, but don't the crocodile leads gets really annoying and in the way of each other after a while? Looks cool though, in a kind of Mad Max kind of way

Quote from: phantompowers on January 18, 2011, 09:21:36 AM
Also, after messing about considerably with all the connections on the patch bay I can confirm that the only pins you need to avoid are 1 and 32. All the other points can be joined in any combination you wish.

I'm guessing 1 and 32 are either both the positive power rail, or one of them is ground. Did you find the pinout for the chip or is it one of those Yamaha specials that you'll never find a datasheet for?

phantompowers · January 18, 2011, 03:47:03 PM

Thanks mate!
Yeah, the crocodile clips do get in the way a bit but I can live with that. If I was doing the job for someone else I would have spent more money on it and built a proper patchbay.
I actually saved the DD-14 from a skip at a local school. It has a huge crack across the whole case and it had chewing gum stuck in the DC socket. After replacing that and cleaning it up everything worked fine. That is why I was so reluctant to spend any cash on it.
I didn't bother finding the pin out for that chip 'cos I figured it was one of those Yamaha specials!

phantompowers · January 24, 2011, 06:53:13 PM

Since making that last video I have performed several more modifications:
1/4 inch jack socket
Two blue LEDs that pulse on the beat
An oscillator that has an LDR for pitch control.
On the video I am demonstrating the affect a strobe light has on it.

Circuit Bent Yamaha DD-14 with Strobe.

phantompowers · January 24, 2011, 06:56:37 PM

I then added an output socket to send a trigger on the beat count.
On this video it is controlling a 40106 oscillator.

Circuit Bent Yamaha DD-14 with 40106 Oscillator.

Remork · July 25, 2011, 11:31:21 PM

just got my hands on a DD-14 here..
since i'm not the "Let's poke around and hope we won't kill it" kinda guy, here's some info that might be useful..

on the MOSEL chip (IC3, ROM) pins #1 and #32 (the one on the corner near the dot and the one straight across) are both connected to the +5V rail. best to stay away from those.
pins #16, #22 and #24 all connect to ground. they're ok to mess with, but they're basically the same.
wired it up, looking for a way ahead (patchbay? keyboard? dunno yet). might take a while.

so far, i did swap out the 12Mhz crystal (cr1) which is responsible for overall computing speed. i felt the original slowest tempo was still too fast, so i put in a 8Mhz crystal. 6Mhz works as well, but then you can see the display leds starting to flicker and the whole thing's response becomes too slow.
i will be replacing the 9.4Mhz (cr2) ASAP with the LTC1799 kit sold here, since it determines readout speed = pitch.

i doubled all the red wires coming from the pads to hook up to triggers, sequencer or whatever - if you hit them with a +5v spike, they trigger the pad sound. applying 5v for longer creates a retriggered drone. makes the marimba sound like an alarm clock

oh, and less volts = less volume. was driving the drone up and down in volume with a doepfer envelope generator.. promising results, since the volume can be CV controlled!

@ phantompowers: mind me asking how you hooked up that 40106? i found a way to flash an LED in time with the beat connected across some legs of IC8, but i like the direction you took it in..

Remork · July 26, 2011, 11:32:12 AM

just tried the LTC - works beautifully! apparently, underclocking too much stops the samples from playing back. total resistance (pot + fixed resistor) should not exceed something like 70K. near that value, some samples start dropping out, which is verrrry interesting if you're into minimal glitchy stuff, it actually starts to re-interpret it's own preset programs

anything over that value stops playback. YMMV, of course.
overclocking introduces digital noise, so no real sped up clean sounds to be had.
am trying different configurations for fixed resistor + pot for maximum mileage.

should i start my own topic about this, by the way? don't mean to hijack.

Circuitbenders · July 26, 2011, 12:57:21 PM

Quote from: Remork on July 26, 2011, 11:32:12 AM
should i start my own topic about this, by the way? don't mean to hijack.

Its fine here, this is all useful stuff to anyone modding a DD14.

Its interesting that running it too slow causes the samples to stop playing back. Am i right in thinking thatyou're just clocking the samples rather than the entire system?
A few drum machines i've tried, like the Alesis HR16, start to randomly drop sounds from the patterns if you set the sample clock too slow, but i'm not entirely sure why. Is it just when you play patterns or when you hit the pads as well?

Remork · July 26, 2011, 05:24:33 PM

yeah, i've got the LTC1799 on the sample clock, and that stops the playback. system clock is steady.
your description of the Alesis sounds exactly like what's happening here - right before the playback just plain stops, there's a small zone where the patterns get holes in them from some samples not starting. not sure if there's a system to it (e.g. the kickdrum dropping first or something similar)?

the pads also drop out - they become unresponsive, or highly unreliable at best. feels like the thing can only play one sample at a time from a certain point on

hooked up the IC3 pins to a D-connector: 25 points + gnd.
IC has 32 pins - left out #1 and 32 (supply), #16/22/24 (connected to D ground), and then #18 and #29 to get to 25 connections. 18 just made clicks on most bends, and 29 was very close to 28 in effect on most bends. whatever. 25 points will be plenty, don't think i'll miss 'em.. now i just need some kind of connector for the 8 trigger points..

Remork · July 28, 2011, 04:31:01 PM

.. so i went with 8 RCA jacks.
small demovid:

Remörk DD-14.AVI

doepfer dark energy and soundlab mini synth both only in there to create CV envelopes triggering the pad sounds.
pitch control demo at 2'15. having the pitch quite low makes all the glitch connections sound very alike, as you can see..
but i wouldn't mind taking this thing on stage without the glitchbay. that pitch control is quite yummy in itself.

at around 4'00 i start the beat, and a bit later there's an audio example of the random dropouts in the rhythm.

what would be nice is to have that 40106 trigger output to clock a 4017 sequencer.. so you can sequence glitches along to the beat

tbone · July 30, 2011, 10:57:04 AM

@phantompowers
That trigger in to the 40106 is great, how have you hooked that up?

@Remork
That multipole socket for the patch bay is an ingenious space saver! I'm going to have to try that.

Remork · July 30, 2011, 02:46:39 PM

Quote from: tbone on July 30, 2011, 10:57:04 AM
That multipole socket for the patch bay is an ingenious space saver! I'm going to have to try that.

thanks, wish it were my own idea.. go ahead, you wouldn't be the first nor last

just scored fleamarket flatcable (5m long, quite excessive) with 2 other female 25pin D connectors still hooked up - breakout box here we come!

so yeah, Phantompowers, how did you hook that thing up?