- Input Gain
- controls the input volume
- 35 Hz, 65 Hz, 105 Hz, 160 Hz, 240 Hz, 360 Hz, 540 Hz, 800 Hz, 1.2 kHz, 1.8 kHz, 2.7 kHz, 4 kHz, 7 kHz, 12 kHz
- control the filters with the given frequencies
- to bypass the effect
- Output Level
- controls the output level
'classic' class-A circuit design using (expensive but great sounding) coils. Only 4 transistors in signal path, 2 of them being selected germanium types, which behave somewhat similar to vacuum tubes.
14 bands with 2-pole-filters. Center frequencies are 35, 65, 105, 160, 240, 360, 540, 800, 1200, 1800, 2700, 4000, 7000 and 12000 Hz.
The choice of the frequencies in (nearly) fifth intervals avoids a false Â´tonalityÂ´ (that is an unwanted emphasis or attenuation of the same musical tone in different octaves) that can be found on all octave, semi-octave, and one-third-octave filterbanks.
The control range per band is +/- 20 dB (!). This corresponds to a ratio of 1/100 compared to 1/16 (+/- 12dB) available on almost all other equalizers and filterbanks. So even drastic sound manipulations are possible that normally require two chained EQÂ´s. The q-factor of the filters gradually increases from 0.7 at +/-10 dB to 6 at +/- 20 dB.
The individual filters are not decoupled from each other. Thus all kinds of - wanted - phase changes and cancellations occur. Normally this circuit design has the disadvantage of a very non-linear control curve (all relevant changes happen within a few degrees at either end of the potÂ´s turn). To compensate this, sealed conductive plastic pots with a special curve are used, custom-made for us by ALPS.
Input gain and output level controls. Input gain can be set from - 20 to +20dB. Due to its special circuitry, overdriving the unit produces much more interesting results than standard rc-filters using op-amps.
Frequency range 20-50000Hz +/- 1.5dB, Signal-to-noise ratio 90dB.
1/4" jacks for input and output. Internal ground-lift for separating chassis and audio ground. A special summing Y-cable can be ordered for connecting stereo sources.
Bypass (using a sealed relay) through frontpanel push-button and automatically when power is disconnected ("hard-wire bypass").
19", 1 unit, depth (behind frontpanel): 58mm + plugs, external power supply. Dual/quad supplies available for multiple units.