Marchand Electronics Bassis WM8 Parametric Equilizer for Low-Frequency Response

Condition: USED, in good working condition.

The equalizer powers on and I was able to run audio in and out of the device with no issues. However, I do not have the type of high-end stereo equipment required to fully test the capabilities of this parametric equalizer. I assume all works fine based on my limited testing. Sound output was clear with no issues.

This item is used and has some minor scuffing on the top cover.

Power cord is included.

WM8 "BASSIS" Bass Equalizer

Adaptable to all acoustic-suspension speakers.
Adjustable bass boost and damping.
23 dB Maximum boost.
Balanced inputs/outputs available.
20 Hz subsonic filter.

The BASSIS is a specialized parametric equalizer with two purposes: (1) to correct the irregular bass response of many acoustic-suspension loudspeakers; (2) to extend the bass response as much as two octaves lower. The damping (Q) of the new bass cutoff can be adjusted according to the listening room acoustics and the user's tastes. In consequence, any speaker can be corrected to obtain deep yet well controlled bass, providing music with a greater sense of impact and "openness".

Curve A is an example of the bass response of a typical "boomy" speaker, with bass falling off below 60 Hz. By adjusting the BASSIS, its own frequency response (curve B) may be made the inverse of the speakers curve, down to 15 Hz. The combination of the equalizer and speaker is shown in curve C, with a smooth response and a -3dB point at 15 Hz. Note that it is generally not possible to perform this sort of correction with a conventional graphic equalizer, due to the spacing of the frequency bands of the sliders.
The BASSIS can also reduce the "boominess" of poorly-tuned vented loudspeakers; or the vent can be plugged for use with the full range of equalizer options.
The BASSIS employs a 4 amplifier bi-quadratic filter, with additional op-amps to allow independent adjustment of the various parameters, and to ensure system compatibility. The circuit contains high-speed op-amps, film capacitors and metal film resistors. Four rotary controls are provided for each channel, to match the cutoff frequency and damping of any acoustic-suspension speaker and to set the bass boost and net damping. A 20Hz high-pass filter (subsonic filter) can be switched in from the front panel to eliminate unwanted subsonics.