Analogue Systems RS-35 External Processor


You want to play your modular system using audio signals? – Then the RS-35 External Processor is just what you need! The module extracts control voltages from audio material. More precisely, pitch signals, envelope voltages and triggers are generated. The tracking is exceptionally accurate. The RS-35 can be flexibly adapted to all kinds of tasks. In addition to playing patches, creative to experimental modulation applications are possible as well.



RS-35 External Processor consists of three functional areas. All sections are supplied with the same input signal. The module can process voltages in the range of -10 V to +10 V. In detail, the following circuits are available:


The section at the top of the front panel analyzes the frequency of incoming audio material and derives a CV voltage. Using a switch, you can choose between two modes of operation:

  • 1 v / oct: The module generates pitch CV voltages in the range of -4 V to +3 V.
  • Var: Here, you can adjust the characteristic via the scale potentiometer. (0 V to 0.5 V) The module outputs voltages ranging from -10 V to +6 V.

A second switch makes it possible to choose between two frequency ranges to be analyzed:

  • 1 kHz: In this mode, frequencies ranging from 20 Hz to 1.2 kHz are processed. (Maximum discrepancy: Less than one percent.)
  • 10 kHz: In this mode, frequencies ranging from 100 Hz to 10 kHz are processed. (Maximum discrepancy: Less than two percent.)

A slew potentiometer allows you to smooth the control voltages generated. More precisely, a glide of up to two seconds can be added.

Without an audio signal coming in, the voltage at the Freq CV output drops to 0 V. With the Held CV out, the situation is different. Here, the most recent voltage value is emitted until the trigger generator (see below) produces a new signal.


This circuit is a classic envelope follower with leveling stage at its output. It can produce signals ranging from 0 V to +10 V. The Env Slew potentiometer allows you to smooth the results. (Maximum value: One second)


Processes signals in the range of 1 Hz to 10 kHz. If the level of the input material exceeds the threshold, a short pulse wave (+5 V) is generated.



Usage with Eurorack:
Analogue Systems' modules are designed solely for use in cases and cabinets made by Analogue Systems. Through the use of adaptors or adaptor cables, however, it is possible to connect them to Eurorack cases.
Should you chose to use an Analogue Systems module in an Eurorack case, please note that the warranties are thus void and the use occurs at your own risk! If the module is plugged in incorrectly and therefore damaged the customer has to bear any costs for repair and shipping!

Because of the different position of the mounting holes there will be a gap of 0.5HP (= 2.5 mm) when mounting an Analogue Systems module next to a Eurorack module. Take this into consideration when planning your system. Gaps can be covered with 1.5HP wide blank panels by Doepfer.


Signal input: Freq-In
CV outputs: Freq-V-Out, Held-Out and Level-Out
Trigger output


3U module in Analogue Systems form factor, 12HP wide, 61mm deep
power consumption: 25mA

0.199 kg
Article Number
availability ? shortly avaliable
€ 19% VAT excl. €200.84 € 19% VAT incl. €239.00
Excl. 19% VAT, Excl. shippingLieferzeit 1