The Doepfer A-101-6 Eurorack Opto FET VCF Phaser Module is a dual purpose Opto FET Multi-Mode voltage controlled filter in the shape of a Eurorack Module. The A-101-6 is made of six serial 6dB filter stages and each stage can run as lowpass, highpass or one of two allpass filter types. A small trim pot on the back of the module lets you adjust the slope and filter type. Being built around OPTO FET circuitry which is stable under high voltage control, the Doepfer A-101-6 is able to produce filter FM style effects with accuracy and almost zero distortion. With the adjustable feedback control, you can add harmonic content and saturation to the audio signal. The analogue filter works round four operational modes and comes with a built in feedback loop.
The main features of the Doepfer A-101-6 Eurorack Opto FET VCF Phaser Module include
This filter is quite possibly my favourite. I love the Pittsburgh LPG for a fat sounding filter, but this one is completely different with lots of character. Super smooth with low resonance settings and very crunchy (but in a really pleasing way!) with increased feedback. I really think this is the best sounding eurorack filter I have tried so far. Its got a dozen or so jumpers in the back - you can set it to different modes - LP, HP, AllPass etc. Low pass is my absolute favourite. I would prefer 1 or 2 jumpers instead of a dozen, but once you find your favourite mode you never have to touch the jumpers. If I had to choose between this and the WASP, I would go for the A-101-6. Really amazing job, Mr. Doepfer!