The R-52 uses two pentodes, type 12AU6. The circuit is derived directly from our award-winning TM-2 filter, but with all the features of our TM-6 filter. A pair of bandpass filters is swept with a Vactrol(tm) control element, a resonant treble filter and a less-resonant bass filter, giving a 4-pole lowpass response. Filter sweep range (approx): bass-only 80-200 Hz, bandpass/lowpass LOW setting 300-1000 Hz, HIGH setting 800-1900 Hz. Filter resonance/Q adjustable from less than 1 to oscillation. Voltage gain approx. 2 with RESONANCE set to 10 o'clock position and INPUT LEVEL set to maximum. Both filters, or one at a time, may be selected and mixed in desired amounts using the front-panel RESPONSE control. This allows for a wide range of equalization and special sound effects. CV inputs are available for sweeping the cutoff frequency and for affecting the treble filter's resonance. Circuit distortion is less than 0.5% typical.
Audio: input and output
CV inputs for cutoff frequency and resonance
3U Eurorack module, 22HP wide, 25mm deep. Tubes protrude from the frontplate 22mm.
Current draw 150 mA.