Grampian Ambiophonic Unit – Type 666

We’ve been fortunate enough to have one of these (pictured above and below) come through our hands; essentially what you have is a broadcast-quality, very clean-sounding Grampian Type 636. So it won’t produce the famous overdriven distortion, but produces a great, rich reverb effect that is good with pretty much anything. Very uncommon, these were apparently built for the BBC and used by BBC Radiophonic Workshop.

Below are links to the documentation we were given – you can view and download from the links below. Note that these were given to us to distribute and are free to use, however if you use, re-post or share them then please add a credit and a back link.

– Original Grampian Ambiophonic brochure & technical spec

– Schematic: Grampian Ambiophonic Unit Type 666

This page is part of our collection of resources on the legendary Grampian Type 636. Read more about this remarkable unit and see all the information we have gathered over the years here. We’re fanatical about these units and sound they can produce if restored to full functioning – if you are looking for one of these units, or have one to sell in any condition, please get in touch.