AV Synth Is Psychedelic Analog Mayhem

Digital video is cool and all, but it can’t compete with analog in terms of smooth, creamy glitches and distortion. [gieskes] has developed an analog audio-visual synthesizer that is a great example of the old-school retro visuals you can create with a handful of simple components.

Known as the 3TrinsRGB+1c, it’s available both assembled and in kit form. It’s probably best to start with the manual. Synthesis is achieved through the use of a HEF40106 hex inverting buffer – a cheap and readily available part that nonetheless provides for excellent results. Video can be switched between RGB oscillators and a series of inputs, and there are various controls to create those classic scrolling effects and other visual oddities.

Additionally, a series of connections to the underlying circuitry are broken out on a header connector. This allows for extra modules to be plugged in, and several designs are available to expand the unit’s capabilities.

Analog video isn’t used so much on a day-to-day basis anymore, but it’s a great technology to tinker and experiment with. We’ve seen some of [gieskes] experiments in this arena before, too – like this Arduino video sampler. Video after the break.


8 thoughts on “AV Synth Is Psychedelic Analog Mayhem


    But wow! That’s amazing! And all analogue? If Atari had done that for their Video Music machine in the ’70s (and they probably could have) it would have sold a lot better and been a lot more use. Particularly if you could do something chaotic to feed a constant source of new inputs to the controls, or perhaps even thermistors to gradually heat up, or somesuch. Some of that stuff is amazing and stuff you wouldn’t see in digital form, in demos, til the 1990s. Bravo! It’s impressive you can feed such nonsense to a TV and still have a stable picture.

    I wonder how much of this is a lucky accident, and how much incredibly mathematical design? Might it be that our guy hit on a sweet spot in the design, from where lots of parameters could be changed, while still producing a valid picture?

    Very, very impressive!

    I’m serious about turning down the volume though!

  2. Ah… seems like maybe the ATMega on there might take care of the strict stuff like HBLANK, VBLANK, and colour burst, leaving the free analogue lunacy to switch in during actual line drawing. Just a guess from looking at the PCB.

  3. It was either what I posted previously or this one. The video you see matches the sound by showing the picture you get on an oscilloscope with x displacement = left channel in the audio track. y displacement = right channel. (I could have the channels reversed here) No scanning frequency on the oscilloscope, just displacement. Also trippy stuff. It’s amazing how sounds that sound cool also look cool, just like what we get from AV Synth in this blog. Enjoy!!! ???? (love that green oscilloscope glow)


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