3320 Filter module

Well, this house building business takes a lot more time than I had expected, and whilst I’v become something of a dab hand at building airing cupboards and fitting out utility rooms, I’m finally coming out of the other side and getting a bit of time to work on my music.

I’ve recently taken delivery of a third Mantis case (someone should have told me this Eurorack hobby would turn into an obsession!) and am working out what modules to put into the gaps.

DIY time

As you can never have enough filters, I decided to go DIY and search for something interesting for the last 8HP of the ‘Analogue Synth’ Mantis case.

This led me to a PCB and Panel kit by Guru Gara Synth, based around the 4-pole 24dB CEM 3320 filter. The filter was used in lots of classic 80’s music technology including most notably the Prophet 5 synth (Rev. 3), the Fairlight II, PPG Wave 2 and the Oberheim OB-SX – none of which I would ever expect to be able to own! (Unless Behringer feels like cloning them of course).

The kit doesn’t come with any build instructions, but the PCB is very clearly laid out, so that’s no biggie. As the CEM3320 has been out of production for some time now, I went for the AS3320 from soundtronics.co.uk which is a modern equivalent and very reasonably priced. From the YouTube videos, it does sound rather nice!

More info on the 3 Mantis cases themselves and how I’ve configured them in a future post.