A-121 d

A new filter circuit from Doepfer! The A-121d is a dual multimode filter that allows for many applications.

The A-121d consists of two separate filters that have individual and common parameters for control. Filter 1 has an individual output for the high-pass and the band-pass output is normalized to the two-channel mixer. Filter 2 also has the bandpass normalized to the mixer, but here there are individual outputs for lowpass and bandpass. The individual outputs, the mixer and the separate audio inputs of the two filters make interesting interconnections possible.

The two filters share a parameter for setting the common cutoff frequencies and a delta parameter, which then separates the frequencies from each other. There are individual resonance parameters, although the module does not go into self-oscillation by default. However, you can easily change this with the trim setting to create a dual oscillator. In combination with the independent frequency CV inputs, you can also create a great percussion generator!

The mixer section, which allows a wide variety of filter combinations, is very exciting. Have a look at the Doepfer website for more detailed information! A great filter module with a new Doepfer circuit and special filter type combinations!

Features:

• Dual filter
• Filter 1 with highpass and bandpass
• Filter 2 with lowpass and bandpass
• Mixer section
• Split and individual parameters
• Special combinations of filter types possible
• Unique Doepfer circuit