AYGOR - the AY Great Official Resource.
This is a short (1024B) demo written in Basic, being a demonstration of mixing two waveforms in a single channel (B). A triangle waveform is generated by the envelope generator (AY registers 11/12/13) and a square waveform is overlayed in the same channel. The overlay causes a constant vibrato effect. Its pitch can be tuned changing values of the tone fine register (in this case register 2). This example is based on one note, but of course it applies to all frequencies. The lower notes give more possibility to control the vibrato. Two other AY channels remain free for generating other sounds.
by Abrimaal, 2013-12-05
AYGOR - the music database
http://abrimaal.pro-e.pl/zx/ay.zip
