Monday, September 1, 2008

Elrad Music Processor

One day some three years ago my friend Fokko gave me a strange and rusty black box with some knobs and jacks that his dad had found in the trash. They thought that since I am somewhat interested in electronics I might have some use for it. Boy, they were right.
Upon closer examination it turned out to be a Flanger/Phaser published in the 6/82 issue of Elrad, a german electronics magazine. (I found out because the name "Elrad Music Processor" was etched on the copper side of the PCB. Yes, that was easy.)
It features DT, ADT (double tracking, automatic double tracking), Flanger and Phaser modes with different timebases, variable speed and amount. It is triggered either with a footswitch or the button on the front panel. And oh yes, it is monaural.
The pots were totally scratchy, someone had made some modifications to it (including a crude guitar preamp of sorts) and it wasnt working that well.
I decided to restore it to the point where it would be useful to me. Some fellow from the SDIY mailinglist kindly send me a printout of the original Elrad article, but it was not that readable... especially the schematics and the component overlay for the PCB foil. Therefore, I put the whole shebang away.

Time passed, legend tells that I left the country.

Fast forward: about a month ago I re-found the flanger. I knew that the whole Elrad backissues are available on DVD, so I decided to invest 20 Euros and ordered it. Three days later I had perfectly readable schematics of the unit. With those it took about an hour (!) to get a working unit. Then I quickly (within 3 days or so... paint and glue take their time) built a 19" case out of some plywood, sheet metal (used to be a case for a CD player) and a 19" blanking panel that I veneered and stained orange.
I am quite happy with the result. The unit sounds nice, looks good and, strictly speaking, didnt cost me a cent since I had everything needed in the restauration process in my parts bin anyway. I currently use it as an insert in my mixing console.

Friday, February 29, 2008

Roland TR 606 - modded

Oh I wish I still had this one!
This is a Roland TR 606 drum machine with an external breakout box. The box features the following controls: Bassdrum PITCH, DECAY and TONE, Snare PITCH, DECAY and TONE, Tom PUNCH (switch) and individual TUNE controls, Noise LEVEL and Hihat FILTER. On its back are individual outputs for the instruments.
There is actually a small PCB with a completely redesigned Bassdrum circuit inside the breakout box. I still have the layout somewhere - I should probably dig it up and make it available to the DIY-community or the nice folks at the forums. I am toying with the idea of building my own drum machine, based on Marko Kanala's MR9090-Sequencer and an assortment of analog drum voices. The modded 606 BD would be a perfect fit.

I loved the 606's simplicity and ease-of-use and it's punchy analog sound. This is a poor mans 808! It is a bit of a shame that the photos are so blurry...
A great little box - sold on Ebay lightyears ago.
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Cruiser Bike 1

My first cruiser bike. I bought it in 1997 (with the first money our government paid me for doing civil service) and a year later I started working on the frame. There is a modelled "tank" on the front end of the bike and some more modifications near the rear axle. They were made out of a Styrodur core and glassfiber + epoxy resin.
I added some parts (twin headlight, 3-speed Sturmey& Archer gearbox, leather saddle, mirror and speedometer) and gave it a two-color paintjob.
I have to admit that I underestimated the work and especially the required sanding involved in the frame modifications, so I got bored and put it aside, working on it for maybe 1 hour every 4 months. At one point the project had to rest for 3 years- when I got back to it the whole frame was rusted and had to be sanded again; God knows why I opted for stripping the whole frame of its original paint instead of just putting a new layer of primer + paint on it.
This is by far the longest running project I ever did - 5 years (!!!) which is ridiculous considering how long it would take me nowadays to finish something similar. It was a good learning experience though, especially to figure out how to not do things...

Hercules BW 125

My German Army motorcycle, a Hercules BW 125 V1 from 1971. I restored the engine, de-rusted the frame and all metal parts (and there is next to no plastic on this thing!) and gave the bike a new paintjob (using the authentic shade of olive).
I coated the tank on the inside with "Kreem White" to prevent it from rusting. Having rust particles in your carburetor simply sucks ass.
Of course, with a bike this old there were so many things that had to be done that I simply cannot list here.
It is a fun bike that turns heads wherever I take it - you gotta love the oldschool fork and overall "dirty little bastard" style of it. Oh, and it has a nice, loud, screaming two-stroke sound. There are different opinions about the reliability of this bike - but it has never let me down in a serious way. I wouldn't go for a ride without tools and a spare plug, of course.

Technics SL1200 mkII - white with blue LEDs

You actually might have seen one like this before, and I really liked the idea behind it.
When I lived in Vancouver BC I used to service Technics turntables. Eventually my friend Paul "Swytch" of Trillbass fame (back then he lived in Vancouver too) sold me a beat-up Tech12 for cheap. I painted it white, gave it a new tonearm and pitchfader, recalibrated it and put new RCA cables in. I changed all the LEDs to blue ones. The special gimmick are 32 blue LEDs that illuminate the platter from underneath. The lights come on when you activate the popup-light. The effect is subtle in daylight but looks stunning in the dark. It was sold to someone somewhere in the US-
I really couldn't take those extra 12kgs on the flight home

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x0xb0x 187

My first x0xb0x. It is #187. For those of you who don't know what a x0xb0x is: it is a clone of the infamous Roland TB 303, with original components in the analog section and a state-of-the-art sequencer. Most clones lack the seq, so this is what makes x0xb0x really outstanding. Go here to learn more and get on the waiting list.
As you can see I was not happy with the stock case, so I made my own. The b0x is made out of beech multiplex wood with an aluminium faceplate which was painted white. The labelling was done with Lazertran paper.

Another shot of the x0xb0x. If you think "Hey, it doesn't have buttons!" then think again - the LEDs are acting as buttons, i.e. you press on the LEDs. I liked the clean look this gave me. Oh damn, I regret that I sold this beauty...

The backside. Note that this one, unlike a stock x0xb0x, does have an ON/OFF switch. Also there is a switch that toggles the Bassboost-mod, right above the USB port.
Again, I sold this nice piece of gear on Ebay to some lucky guy in Austria.

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Roland TR 707 - Circuit bent

Tr 707 with external patchbay and individual 555-based oscillators that allow for tuning of the voices.
I do not own this machine anymore, some lucky guy bought it on Evilbay. Yes, I do sell stuff there.

Inside the TR 707. The new PCB that holds the 555s and the pots are visible.

External inputs for Hihats and Ride. They work like an audio gate- when you insert a plug the Hihats / Ride is silenced and the external signal passes throught the corresponding VCA. Gatelength can be set with the pots below the instrument buttons - great for chopping pads.

The banana plug patchbay, connected with a standard 25 pin sub-D connector. There is a 5x5 matrix for circuitbending mayhem. The 5x2 row at the bottom is connected to the switches - so your favourite connection can be switched on and off with the flick of a switch. Easy, fun and convenient. Oh, of course the plugs are stackable, for even more possibilities.
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Well... everyone and their Grandma seems to blog about themselves - so I figured I'd use this as an outlet to showcase some stuff that I made over time. I don't claim that I reinvented the wheel so if something looks familiar to you chances are that at some point both of us visited the same website. Yes, sometimes I copy stuff. The point is: The things you see here were built or modified by me and I enjoyed doing it.