Amdek Chorus Kit
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There are two ways of looking at electronics construction kits — cash and creativity. You can build your own effects unit because it's cheaper than buying a production model, or you can dabble with the soldering iron for the satisfaction of completing the job yourself.
Amdek falls into the second category because it isn't actually much cheaper than the real, finished macoy to be found in shops the length of the land. The kit under construction was the £60 chorus, and Ibanez, Boss, even MXR, all do pedals around that price.
Let's say from the start that Amdek gives a highly professional result — indistinguishable from a factory-made item in sound, quality or appearance — but obviously producing a kit that can be built to such a standard is not going to be cheap.
The case has to be moulded and silk screened, the printed circuit board (the toughest part of the job) is ready assembled with components soldered into place, even all the bits you have to add come sealed in individual plastic bags.
So Roland have sacrificed price-saving in order to market a kit which is almost impossible to get wrong.
The chorus, like the rest of the series, comes in a plastic, bubble pack. The heart of the operation is a clearly written sheet of instructions relying on diagrams and colour coding. There were 19 steps in this sheet, each with a box to be ticked when you've completed the task. To prove Roland believe in taking no chances, the first instruction is: "Turn on the power supply to the soldering iron".
The 15 to 30W iron is part of a list of recommended tools such as cutters and strippers, pliers and a cross-head screwdriver, but other than that everything is provided — leads, solder, screws, even a special spanner to tighten the fastening nuts.
About three-quarters of the work involves simple interconnections between existing bits. Coloured leads have to be cut to the proper length (a scale is printed on the assembly manual) then stripped to take solder. No need to add a few millimetres to be on the safe side, the measurements given are all more than adequate, and there are tips on stripping and soldering.
In all there are only 18 connections to be made. There are two potentiometers with three wires each, soldered at the pot and circuit board ends, an LED with two leads, a battery clip with another two and the footswitch making the final pair.
The only slight confusion came with the footswitch where it wasn't really made clear that it didn't matter which of the wires was connected to which terminal on the PCB. But then since you couldn't get it wrong, it could hardly induce a fault.
The PCB terminals are numbered AND carry a written description on the board. Each step virtually has its own plastic bag of components, so providing you don't open them all at once you should never get confused or find bits missing.
Sometimes Roland even deny you things to do. One step advises filling the PCB terminal holes with solder, but 'lo the eastern iron has been there and done the job for you already.
The footswitch is a cunning piece of design containing two springs and a screw-on metal guide to ensure you put the entire arrangement under just the right tension. The final assembly involves a small amount of jiggling to get the board and jack sockets into place, then it bolts down firmly using the Roland wrench.
The last few moments are spent fitting the sponge to cushion the battery, the stick on non-slip rubber feet and the two front panel knobs.
In operation the Amdek gives a smooth, fairly deep chorus effect though I would have liked a shade more top speed on the rate control to give fast, Leslie-like vibrato.
It does introduce hiss to the signal, though an acceptable amount for live work, doesn't cut back the volume too much and leaves the treble almost entirely intact.
The CHK-100, as it's code-named, has a red LED to tell you the chorus is on, will accept a 9V power supply on a mini jack socket, and has twin outputs for a stereo chorus effect if you want to split the signal.
Since there's only one PP3 cell running the gadget, it might not go for too many hours of continual use, but that's a consideration that applies to all chorus units, buyer-built or otherwise.
If you've never touched a soldering iron before (a hint — you pick it up at the cool end) then Amdek is a great place to start. The steps are easy and the results gratifying. I've done some work like this before and it took me under an hour to finish the job, from unpacking the bits to plugging in the guitar, and it worked first time.
Experienced constructors would find the Amdek range too patronising. A vast amount of the more challenging work, such as identifying and soldering in components, is already done and, in a sense, Amdek is only a wiring job.
Having completed something like the chorus unit it would be unwise to think you could then press ahead and knock up a nuclear power plant in the back garden using only the inside of your mum's hairdryer and an empty tube of Fosters.
It's an enjoyable and reliable introduction to electronics but not a PhD course.
PS: If you do run into trouble during construction, Roland UK operate a 24-hour recorded telephone advice service on (Contact Details).