The HD-231 is dual, 31 band, 1/3 octave graphic equalizer ideal for live sound systems, PA systems, permanent or fixed Installations, church systems, nightclub systems, practice PA systems, DJ sound systems, as well as home and project studios. With so many useful features and rugged construction, the HD-231 EQ will prove its value with every gig and live performance.

Extended information

HD231 - Dual 31 band Graphic Equalizer Features
• Accurate Constant Q Precision Center Frequencies
• Exceptional Frequency Response at 20-20KHz, +/-0.5dB
• Equipped with XLR, 1/4” Phone and Euroblock Barrier Strip Connectors
• Independent Variable Hi and Low Pass Filtering deliver optimum control
• Automatic Bypass Relays provided in case power is lost to the unit
• Extremely Quiet Operation
• Rugged Chassis Design

Technical specifications

Controls:
Overall Gain Range:
Off to +6dB (Unbal. out) Sliders Centered
Off to +12dB (Bal. out) Sliders Centered
Filter Type Constant Q, 3% Center Frequency
Input/Output Connections

INPUTS:
• Input Type: Active Balanced/Unbalanced
• Connectors: 3-Pin XLR, 1/4” TRS (Bal.), Euroblock
• Impedance: 24k Ohms (Balanced); 12k Ohms (Unbal.)
• Maximum: Level +22dBm (Level Control at Center)

OUTPUTS:
• Type: Active Balanced / Unbalanced
• Connectors: 3-Pin XLR, 1/4” TRS (Balanced), Euroblock
• Impedance: Typical <150 Ohms
• Max Level: +22dBm (Bal., 600 Ohm load) +16dBm (Unbal., 2k Ohm load)
• RFI filters: Yes
• Bypass Switches: Yes, Passive
• Overload: LED Threshold 6 dB below clipping, (all filters set to flat)
• High Pass Filter: 10-250Hz, 12dB/Oct
• Low Pass Filter: 3k-40kHz, 12dB/Oct
• Frequency Response: 20-20kHz, +/-0.5dB
• THD + Noise: less than 0.01% (20Hz-20KHz, 0dBu)
• IM Distortion (SMPTE): 0.005%
• S/N Ratio: >98dB, Ref: 0dBu, (Bal.) 20Hz - 20KHz, unweighted.
• Headroom: +22dB, Ref, 0dBu, (Bal.) (+/-6dB and +/-12dB range)
• Dynamic Range: >117dB, (Bal.)
• Channel Separation: >60dB
• Common Mode Rejection: 50dB typical

Power 95-125VAC, 50/60Hz, 190-250VAC, 50/60 Hz
Power Requirements Input AC Power: 14 Watts, typical
Range +/-6dB or +/-12dB (Selectable)
Size 3.5"H x 19"W x 7.0"D
Slider Travel 20mm (Positive Center Detent)
Weight 12 Ibs (5.4 kg).