Boss PRO PQ-50 Mono Parametric Equalizer 1/2 Rack, 1991, made in Japan

Link: Owner's Manual

Specifications:

Frequency Response:
10Hz to 30kHz +1/-0.5dB (Flat, Level Switch: -10dBm)

Nominal Input Level:
-10dBm/+4dBm (selectable with Level Switch)
Input Impedance:
1ΜΩ
Nominal Output Level:
-10dBm/+4dBm (same as Nominal Input Level)
Recommended Load Impedance: 50kΩ or greater
Total Harmonic Distortion: 0.03% or less (IHF-A, Flat, Level Switch: -10dBm)
Residual Noise Level: -97dBm or less (IHF-A, Flat, Level Switch: -10dBm)
Equalizer Control:
* Center Frequency
- Low: 20Hz to 500Hz
- Low Mid: 125Hz to 2kHz
- High Mid: 500Hz to 8kHz
- High: 2kHz to 20kHz 0.8 to 14
* Variable Range
±20dB OdBm=0.775Vrms

Controls:
- Input Level Knob
- Frequency Control Knob X 4
- Q Control Knob X 4
- Level Control Knob X 4
- Equalizer Switch
- Power Switch Level Switch

Indicators:
- Power Indicator
- Equalizer Indicator
- Overload Indicator

Connectors:
Input Jack (1/4 inch phone type)

Output Jack (1/4 inch phone type)

Equalizer Remote Jack

AC Adaptor Jack (AC 12V)

Power Supply:
AC12V: AC Adaptor BRA-120, 220, 240

Current Draw: 500mA

Dimensions: 218 (W) X 234 (D) X44 (H) mm 8-5/8" (W) x9-1/4" (D) X1-3/4" (H) inches

Weight: 1.2 kg / 2 lbs 11 oz

Accessories:

AC Adaptor BRA-120, 220, 240

Foot Rubber X4
Owner's Manual

Options:
Rack mount Adaptor RAD-50
*Not attachable to Rack Mount Adaptor RAD-10. Foot Switch FS-5L

*In the interest of product improvement, the specifi cations of this unit are subject to change without prior notice.

Owner's Manual: