Doepfer released A101-8 (8-stage phase shifter)

A-101-8 is a 8-stage phase shifter which uses light-sensitive resistors (LDR) and is a replica of the Compact Phasing A manufactured by the company Schulte in the seventies. The actual phasing circuit is identical to the historic model. Only the illumination control of the LDRs is different: the A-101-8 uses LEDs to illuminate the LDRs, the historic model used incandescent miniature lamps. And the A-101-8 has no built-in LFO but can be controlled by any external control voltage source (e.g. LFO, ADSR, random, Theremin, ribbon controller, sequencer, midi). The phasing offset (i.e. the base value for the phase shifting) and the modulation depth of the external control signal can be adjusted separately. The Compact Phasing A had no offset control but only a depth control for the built-in LFO. Feedback and mixing ratio of the output signal are set by two controls. The audio input is equipped with an attenuator. The module has two audio outputs available (same as the historic model) and a visual display of the phase shifting.

The historic model had two audio inputs: one 5-pin DIN socket and a 1/4″ jack socket. The DIN socket was intended for high-level line signals. When the 1/4″ jack socket was used the amplification of the pre-stage increased by about 100. The 1/4″ jack socket was intended for low level signals (e.g. electric guitars or microphones). For this feature the A-101-8 has an internal jumper that can be used to increase the amplification. As long as the module is used within the A-100 system usually the lower amplification is used to avoid distortion.

The 8 photo resistors and LEDs are assembled within an small lighproof box. In addition the pc boards are made of lighproof black material to avoid interfering light from other modules or the bus board.

The following document shows the positions and functions of the jumpers and trimming potentiometers of the module: A101_8_trimming_potentiometers_and_jumpers.pdf
Pay attention that faulty adjustments caused by the user are not covered by warranty. In this case the working time required to re-establish the correct adjustment has to be charged.

Price
Standard Version : Euro 140.00
Vintage Edition : Euro 150.00

More info here: Doepfer | A101-8