Description

This DSP Musicolour accepts audio input signals and drives coloured lights ‘in tune’ with the music. Its four output channels respond to different audio frequency bands, and the brightness of the lights is in direct proportion to the amplitude of the frequency components. A dot-matrix LED menu display is featured on the front panel, and this also functions as a spectrum analyser or VU meter.
Nearly all of these projects were analogue designs, based on op amps and logic ICs. The audio was passed through different pass-band filters for each channel, and the filtered outputs were used to drive either phase-controlled triacs or power Mosfets in switch mode. The logic ICs were also used to produce chaser modes, which were alternating patterns controlling the output channels in the absence of an audio input. These chaser modes meant that you could have pleasing lighting effects without any music. Two decades on, we now present the DSP Musicolour, a full digital design using DSP (digital signal processing).
It is based on a single DSP microcontroller to produce a comprehensive list of features that were simply not possible with previous analogue designs. The DSP Musicolour operates from 230V to 240V AC or 115V to 120V AC mains (detecting the 50Hz or 60Hz mains frequency automatically) and drives four channels of incandescent lights. The total power output rating is 2400W for the 230V to 240V AC 10A version and 1600W for the 115V to 120V AC 15A version. For the 240V AC version, each channel is rated at 800W maximum (as long as total power is less than 2400W). For the 120V version, each channel is rated at 400W.

By making the design suitable for both 230V to 240V AC and 115V to 120V AC 50/60Hz mains supplies, we are ensuring that the DSP Musicolour can be built in any part of the world without modifications, apart from changing the power transformer’s primary connections.