The C64 has some very advanced sound features but no-one has exploited them fully until now.

Ultisynth is a full synth package for the Commodore machine and requires no extra hardware. The computer keyboard is used for all effects and also for playing the notes. While it's not the ideal solution, it is cheap and works adequately.

The program comes on cassette and is complete with a comprehensive 50 page manual. The full potential of the program is beyond the cope of the manual and, although it details all of the system's functions, the only way to really get to know it is to sit at the keyboard and play.

Loading the tape takes just over seven minutes which gave me a little time to read the manual and to appreciate the complexity of the program. Once loaded, the main menu allows you to choose one of the seven options.

You're recommended to try option one first, so I did. This puts you into record mode, where you actually enter your tune into memory. Unlike any other similar program I've seen for any micro, this allows you to play in real time. What this means is that, when you play back your masterpiece, not only will the notes be as you played them but so will all the timing as well.

The alternative to this is called Compose Mode, where the notes will simply be played back one by one with a fixed delay between each. The delay can be set by the user. This program has a compose mode as well.

Playing from the keyboard uses voice one while voices two and three are for pre-set rhythms and accompaniments which you can program and then play along to. It's possible, and also quite fun, to have all three voices playing at once.

Obviously there are facilities to set different waveforms for each voice, alter the envelopes and add special effects like glide. Then there are pulse wave and pulse width commands, lo and hi pass filters and layering of voices. You can also synchronise the voices. When you've worked out all that, you can progress to modulation, pitch-bending (sounds like a sport) and more clever stuff.

And when Symphony Number 1 for Three Commodore 64s is complete, you can save the whole thing to tape in a form which the computer will reload at a later date, just in case you discover you've left two consecutive fifths together. (That's a musical term, by the way.)

That's not all. There's a lot more in the manual, and there's plenty that isn't too. You'll discover so much by just sitting at the machine for a few hours. And the final results are pretty impressive too.

This is certainly highly recommended for serious music enthusiasts and budding Beethovens everywhere.

Ultisynth runs on a Commodore 64 and is produced by Quicksilva. It costs £14.95.