dbx / 231s Graphic Equalizer

This compact, 31-band, 2-channel graphic equalizer features 20mm faders. Each filter's boost/cut range can be switched between ±6dB and ±12dB, allowing for precise adjustments.

■Graphic Equalizer

■Stereo 31-Band

■2U

【Input】

Connector: 1/4"" TRS phone, XLR female (pin 2 hot)

Type: Electronically balanced/unbalanced

Impedance: 40kΩ (balanced), 20kΩ (unbalanced)

Maximum Input Level: >+21dBu (balanced/unbalanced)

CMRR: >40dB, typically >55dB at 1kHz

【Output】

Connector: 1/4"" TRS phone, XLR male (pin 2 hot)

Type: Impedance-balanced/unbalanced

Impedance: 100Ω (balanced), 50Ω (unbalanced)

Maximum Output Level:

>+21dBu balanced/unbalanced 2kΩ or higher

>+18dBm balanced/unbalanced 600Ω

【System】

Bandwidth: 20Hz to 20kHz, +0.5/-1dB

Frequency Response: <10Hz to >50kHz, +0.5/-3dB

Dynamic Range: >112dB

S/N Ratio: >95dB

THD+Noise: <0.003%

Inter-Channel Crosstalk: <-90dB, 20Hz to 20kHz

Function Switches

EQ Bypass: Bypasses the EQ section

Low Cut: 50Hz 12dB/octave high-pass filter

Range: +/- 6dB or +/- 12dB

Power Supply

Voltage: 100VAC-240VAC 50/60Hz

Power Consumption: 15W

Weight: 6.2 lbs. (2.81 kg) Shipping weight 7.9 lbs. (3.58 kg)

Dimensions: 3.5"" (8.9cm) H x 6"" (15.24cm) D x 19"" (48.26cm) W

【Differences from 231】

Black → Silver

Dynamic Range: 108dB → 110dB

S/N Ratio: 90dB → 95dB

THD+N: 0.004% → 0.003%

Inter-channel Crosstalk: -80dB → -90dB

■Input Gain Control

This control sets the signal level to the equalizer. Gain is possible from -12 dB to +12 dB. The effect can be seen by viewing the output level bar graph.

■EQ Bypass

This switch removes the graphic equalizer section from the signal path. However, the bypass switch does not affect ""Input Gain"" or ""Low-Cut Filter"".

■EQ Bypass LED

This red LED illuminates when the EQ is in bypass mode. Note that bypass mode only affects the graphic equalizer section. Input gain and low-cut controls remain unaffected while the EQ is bypassed.

■Boost/Cut Range Selection Switch and LEDs

This switch selects one of two boost/cut ranges (±6 dB or ±12 dB) used by the equalizer. The red LED illuminates when the ±12 dB range is selected.

■Output Level Bar Graph

These four LEDs indicate the equalizer's output level. The red LED (+18 dBu) is 3 dB below clipping.

■Clip LED

This red LED illuminates when the internal signal level reaches 3 dB below clipping. This can occur when any of the following occurs:

1) Input signal is greater than +18 dBu

2) Excessive gain is applied by the input gain control

3) Excessive boost is applied using the frequency slider

■ Frequency Band Slider Controls

Each of these sliders boosts or cuts the indicated frequency within a range of ±6 dB or ±12 dB, depending on the position of the BOOST/CUT RANGE switch. When all sliders are in the center detent (clicky) position, the equalizer output is flat.

■ Low Cut Enable Switch

The LOW-CUT switch inserts or removes a 50 Hz 12 dB/oct low-cut filter from the signal path. The low-cut filter is enabled when the LOW-CUT switch is pressed.