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Cheap DIY drum trigger converter: The Triggerlution

It’s hacking time again. My friend Fabian is the drummer in our band and we both thought about building some kind of drum trigger-to-MIDI solution, as cheaply as possible. Commercial plug-and-play solutions are expensive, but we have two cheesy 1990 Yamaha DD-11 digital drum sets (pdf manual). These are quite cheap and have eight trigger pads and MIDI out (and that’s what we need; of course you can play the 100 built-in rhythm and accompaniment sets if you’re into casiocore music).

The plan now was to check if the built-in drum pads can be substituted by regular professional pads like Roland’s V-Drum pads. Actually they work like a charm and so we began taking apart the first DD-11.

As you can see, the DD-11’s eight pads are made of aluminum discs covered with rubber. A simple piezo buzzer converts the hits into short current peaks. Commercial or diy drum pads (like this tutorial at the eDrum project shows) work absolutely the same way. For this project, we only want the DD-11 circuitry and will abandon the orginal case, built-in loudspeakers and trigger pads (which we will keep for future projects).

We hurried a little with this first version, so we kept all the internal electronics. When I do the second conversion, I’ll try to leave out the original amp circuit as well. The amp and power supply circuits are a single module and I could not yet figure out what parts can be left out.

The green mainboard is the most important item here. The small board on the right holds the power switch and volume slider. The brown board on top contains the MIDI in/out (left part) and power/amp circuits (right part). We had a little trouble finding a proper case for the electronics. Most commercially available cases are too small or too expensive and we finally settled for a sturdy metal tool case from Bauhaus (diy store) for 7 Euros only.

I’ll skip the build process itself because drilling holes is not really interesting. Here’s a summary of what we did:

• get everything needed out of the original case, desolder everything else
• cut out the original button/display area and reattach it to the board
• solder eight 1/4″ TRS jacks to the original pad connectors
• desolder all original jacks and relocate those needed to new jacks in the case (MIDI out, Audio out)

There’s no way to change settings without opening the case, but Fabian decided that would be okay for know. The device just starts as soon as a power line is connected, always using its “00″ setting with a certain fixed allocation of pad number to MIDI note. The sound to be played on that event will be set on the sampler to be connected to the MIDI out. In the end there’s no use for opening the case.

Fabian dubbed his new spanking red contraption the Triggerlution. Please ask in the comments if you want to know more. I just found this description of a similar conversion (putting a DD-11 into a 19″ rack) on the net. He did what I was also thinking about for Triggerlution v2: Relocation of the keypad area by rebuilding it on a new board.

NitroTracker now first wireless MIDI sequencer of the universe

0xtob has released the new 0.3 version of his Nintendo DS NitroTracker, now with full bidirectional DSMIDIWifi functionality! w00t! The wait for my DS launcher card becomes longer every second now…

Basically, NitroTracker will now act as a wireless sequencer for any software (or computer-connected hardware) instrument. I believe this is a first. It’s not the wheel, but the first wireless MIDI sequencer software evar (though you can use M-Audio’s MidAir technology similarly).
Vice versa, NitroTracker now plays back samples via incoming MIDI note messages. I can’t think of a sensible application for that feature right now, but surely the crazy people on the interwebs will put it to good use.

I’m sure there are legal reasons to consider, but I really can imagine that you could sell a bundled DS launcher card pre-loaded with this and other software some time in the future, say NAMM/Musikmesse 2008. Running homebrew and all that diy fumbling can be a little to arcane to some musicians and I guess there always is a target group that just wants a boxed product.

Controllers in the house

Happy 2007 everyone. Look what I did with the cash the tooth fairy (or whatshisname) put in my stockings for that recent public holiday:

An M-Audio Oxygen8 v2 MIDI Controller (25 keys, 8 knobs and some switches) and a pink Nintendo DS. Yes, pink.

The geek friends’ peer pressure (and the fact that 0xtob made the fantastic wireless MIDI software DSMIDIWifi; basically only that) finally convinced me that I needed a DS too. Still waiting for my R4DS card that will enable me to use all that fine homebrew software, though. Orders from Hong Kong seem to take some time due to the recent earthquake in Taiwan. Until then I have to resort to Brain Age as my only (borrowed) game.

The Oxygen works nicely and came with a “lite” version of Ableton Live which I’m now trying to get addicted to so that at one point I just have to invest the 260 Euros for an upgrade to the full version. Talk about follow-up costs.

Chicas y robots

Hope you all had great holidays, I’m off to Berlin’s annual Chaos Communication Congress now. Meanwhile, enjoy La erótica del robot (via BoingBoing):

Robot nativity scene

On Sunday, I have been at Berlin’s Lido club for a little christmas party with several bands and artists and they had set up this cute robot nativity scene by Markus Kolb:

And if you don’t remember what christian folklore is about, get an update by having the bible explained with LEGO bricks.

Envelope generators

The great GetLoFi blog recently featured the Bugcrusher downsampling circuit by Tom Bugs who suggested in the post’s comments to get the needed AD781 chip for free (usually about $10) via Analog Devices‘ free sample offer (they send you up to three chips as free samples).

So I ordered two AD781s and one AD633 for this ring modulator thing. They are sent from different shipping centers and the single AD633 arrived yesterday. See if you can spot it on the picture. Should I feel bad now for saving $25 worth of chips and at least the same amount on international shipping? I guess not.

An ephemeral machine with built-in dysfunctions

I saw this leaflet on a bulletin board at university. Sounds interesting. Maybe someone with a real understanding of electronics can help him? I guess I should ask him about his project in some months to see what he made and how long it lived.

Coming up next or never

Currently I’m building a little noisemaking device, basically following the Your First Synth schematics by Music from Outer Space.

I also odered some 555 and 556 timer circuits to toy around with and build the so called Atari Punk Console and similar things. Actually, I do not really need the finished devices, or rather, I don’t know yet what to use them for — like with Lego bricks, the creation is the more satisfying part of the game. That usage may appear spontaneously or not at all, but I like having strange artifacts laying around for visitors to play with. In case of the noisemaking device (I’ll post some pictures in the next days) I will give it away as a gift to a musician friend.

Still in the thought queue of things to make:

• An analogue tape echo/delay. The plan is to hack up four (identical) walkmen and a fifth tape player with a recording head, fix it all on some wooden board and have a tape loop running continuously. Electronics would include switches for the echo depth, basically switching the play heads on/off and a pot for motor speed, ie. echo delay time. Another simpler idea is to use an old double tape deck with one tape loop in two prepared cassette shells, so that audio is continously recorded on deck 1 and played back with a delay by deck 2.
• I recently bought another b/w TV on ebay, a 70s model in an orange plastic case. I want to fit one of the above noise maker circuits inside and feed the output into the deflection coils like in the Wave Vessel/Wobblevision. The sound must not necessarily be heard, so it would be some kind of piece of digital interactive art: A TV with several unlabeled knobs and switches that shows a strange picture you can alter using these controls.
• Another idea from today involves an old 70s turntable, also in an orange plastic shell turned into a new instrument. Besides a speed controller for the motor (to play records at unusually low or high speeds), I would add a small noise circuit like the aforementioned APC and one or two small sampling circuits. These are found in cheap “memo” devices that can record several seconds of audio in low quality. I tinkered with a free giveaway memo keychain once and produced nice aliasing effects by changing the resistor on the small board, enabling ultra-low sampling and playback rates. So the turntable would feature two of these memo circuits to sample audio snippets from the record and to play them back once or continuously. Add some controls to mix the various sound sources and you have a strange sonic artifact.

Nintendo DS = wireless MIDI controller

Tob has just told me about DSMidiWifi — a program for Nintendo DS handheld gaming consoles that sends out MIDI data to a host application on a computer. Play any MIDI instrument, virtual or real, by tapping on the DS’s touchscreen, KaossPad-style. (Actually, you can control anything controllable via MIDI, which is about everything electrical in existance, given the right interface.) Chiptune fans also can have the DS receive MIDI data in realtime and use it as an instrument.

Now I really consider having a DS on my x-mas wishlist…

No hay bending.

I might be a sloppy researcher (in a way that using Google means researching), but are there really no people doing circuit bending and related hacking here in Berlin? Surely there must be some artists (not necessarily musicians) and noise explorers in the gallery scene, but where’s the basic lo-fi hands-on approach for the kids? Spaß am Gerät, so to say?

Please drop me a line if you are already doing something like that here in Berlin, or if we could work something out.

(Finally, I still feel a little stupid for passing a Casio SK-1, circuit benders’ favourite victim, on a flea market for 20 Euros some months ago. Having paid the same price for mine years ago, I was subsequently frustrated to learn that it now fetches a lot more on ebay and is not at all something you come across a lot anymore.)