Doepfer A-105 SSM 24dB Low Pass


The A-105 is a 24dB low pass filter that bases on the SSM 2044 chip that was used amongst others in following units: Korg Polysix, Korg Mono/Poly, Fairlight II, PPG Wave 2.2 und 2.3, Emu SP-1200, Siel DK600, Siel Opera 6. The first Prophets used the SSM2040 - the precedessor of the 2044 - that generates a very similar sound. The filter convinces with a very powerful sound. The resonance starts quite early to color the signal and makes a big range of sounds possible up to self-oscillation. The latter provides a very clean sine wave - no wonder, because the SEM2044 chip wasn´t designed only as a filter core but also as a sine wave oscillator.



The A-105 bases on the patented so-called "true open loop design" which generates a very fat sound. The filter works with a slope of -24dB per octave and provides voltage controllable resonance up to self-oscillation. The audio input is sensitive so you can distort the audio signal at the input if desired. there´s a volume control at the audio input, potentiometers for setting the cutoff frequency and resonance as well as attenuators at the CV inputs for cutoff and resonance.


Audio input, audio output
two cutoff CV inputs: 1x 1V/octave, 1x with attenautor
resonance CV input with attenuator


3U Eurorack module, 8HP wide, 41mm deep
current draw: 30mA

0.17 kg
Article Number
availability ? shortly avaliable
€ 19% VAT excl. €100.84 € 19% VAT incl. €120.00
Excl. 19% VAT, Excl. shippingLieferzeit 1