Gameboys are great, but arguably the classic analogue chip sound belongs to the Commodore 64.

The C64 was my very first computer, one that my parents got me when I was only about 4 or 5. As a result, it holds a particularly special place in my heart. Sadly the actual one that I had from back then disappeared at some point, but I tracked down a replacement later on, complete with one of the coveted working 6518 sound chips (or ‘SIDs’).

For ages I’ve wanted to bring the C64 back to life and use it as a vintage analogue synth, but the space required to leave it set up was always prohibitive. In my foray back into music, I decided it was time to take the plunge.

I already had all the bits and pieces I needed, including a really sweet expansion device called the ‘MSSIAH‘ cartridge, which plugs into the back of the ‘breadbin’ and adds MIDI support. Making use of a composite video to HDMI convertor that I use for my N64, I hooked it up to a monitor, and hey presto…

My desk is a bit of a jumble just now with various things on the go, but that’s not where it’s going to live permanently.

For the technically curious, here I’m using a C64 DIN out to phono/composite cable, with the video end going into an AVI to HDMI box for the monitor, and the audio portion connected up to my headphones using a phono coupler and phono to mini jack cable. This is just the testing setup though. When I switch to actually recording with it, I’ll be using a VGA monitor and running the phonos straight to a mixing desk for output.

I’m going to use it in a couple of different ways: to play directly as a synth, but also as an external synth controlled by the Gameboy, using LSDJ as a sequencer (see my previous post on this…). Using a MIDI thru box, I could run different channels into different devices simultaneously, which would sound amazing.

There’s loads of things to explore with the C64, which is pretty exciting, and should keep things fresh. Here’s a couple:

C64 SD tape emulator – To save sounds and patterns and all that you need an external device to store them on. The C64 used to rely on either cassette tapes (!) or floppy disks… and not the kind that most people are familiar with, but large, 5 and 1/4″, truly floppy disks. As it turns out, I actually have both of these…

  
  
but they’re not the most practical – taking up a lot of space and being a pain to use. In the past few years some intrepid people have developed gadgets such as a C64 cassette tape hardware emulator – that plugs into the back and allows you to save onto SD card. They’re pretty smart, but relatively pricey, so I need to see how much I’m actually going to use the thing before I commit.

Second SID – You can install two sound chips in the C64 with a bit of modification so that it can play polyphonically, and make it really sing. This doesn’t look too difficult to do, and could be a fun project for later down the line. I’d be interested to see if I can run two different chips (with different sound qualities) simultaneously, but I’m not sure if it’s possible because of voltage etc. Needs further research.

Picture upscaling – the video output was never designed for modern monitors, and certainly not to be run over HDMI at 1920×1080. As a result, the picture looks terrible – and the controls are almost incomprehensible with my crappy eyesight. I’m sure there are ways to improve upon it, such as through the use of a decent upscaler, but it also needs a bit more exploration.

The most important thing though, is getting it working as a synth first and foremost. At the moment, the sounds sound pretty weak. I suspect that might be because I’m not running them through an amp – so I’ll check that out. I’ve ran the diagnostics and the chip is fine, so it’ll require a bit more investigation. Just a matter of getting time to sit down and play with it.