ART HQ-231 Professional Dual 31-Band Graphic Equalizer with FDC

Item # EFFHQ231
| Mfg # HQ231
| UPC # 840402011637
Our Price: $329.00
Retail: $539.00 | You Save: 38%
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The HQ-231 Dual 31-band Graphic EQ is perfect for any live sound application where there is a high feedback potential including monitor mixes, side-fill cabinets or high powered front-of-house mixes situations.

The HQ-231 features ART's proprietary FDC (Feedback Detection Circuit), with constant Q circuitry capable of delivering a 3% center frequency accuracy. Professional features like LED level metering, selectable 6dB or 12dB slider range, active balanced and unbalanced input & output connectors, RFI filters, independent variable Hi Pass (low cut) and Low Pass (high cut) filters, variable input level control, passive bypass switch, clip level indicator, ground lift switch, and selectable line voltage switch make it ideal for any professional application or touring system.

FDC Feedback Detection Circuit
FDC (Feedback Detection Circuitry - designed and developed by ART Engineering) instantly illuminates an LED on the corresponding EQ band fader with the greatest sustained signal. The LED indicators can immediately show which band corresponds to the feedback frequency, allowing the sound engineer to reduce gain in that band to quickly kill the feedback while having a minimal impact on the sound of the live program material.

The FDC also acts as a simple spectrum viewer while the concert proceeds showing where the 'hot' areas are. During system setup and sound check, the FDC may be used to help identify room and sound system resonances. By increasing the gain until feedback, it is easy to identify those frequencies that are likely to be problems. Reducing the gain in these bands helps tune the sound system, and, remove problem areas before the show begins. It also helps increase the gain margin before feedback.

Constant-Q Filtering
The HQ-231 features Constant-Q Filtering, which helps the HQ's FDC work with greater efficiency while offering superior overall performance of the EQ. Constant-Q ensures that even when making radical adjustments to a frequency band, that adjacent bands will not be affected. This is particularly critical in professional applications including monitor mixes and feedback control.

Professional Feature Set
Professional features like center detent sliders with selectable boost or cut range of 6dB or 12dB ensures the HQ-231 can be used for radical tone shaping, or precise control of a sound system. Versatile connection to any live sound system or installation can be easily made using balanced XLR, 1/4-inch TRS and unbalanced RCA input and output jacks included on the HQ-231 back panel.

High and low pass filters, analog level metering, variable input level controls, signal clip level indicators, ground lift switch, internal power supply and selectable line voltage complete the HQ-231 Dual 31-Band Graphic EQ's full feature set.

  • FDC Feedback Detection Circuit
  • Dual Channel 31-Band Graphic Equalizer
  • Output Level VU Metering on Each Channel
  • Constant-Q Filtering
  • Individual High and Low Pass Filters on Each Channel
  • Center-Detented Frequency Band Sliders
  • Independent Level and Bypass Controls on Each Channel
  • Relay Bypass - If Power is Lost, Signal Will Still Pass
  • Variable Input Controls
  • Signal Clip Level Indicators
  • Ground Lift Switch
  • Input Connections: XLR-F balanced, 1/4-inch TRS balanced, RCA
  • Output Connection: XLR-M balanced, 1/4-inch TRS balanced, RCA
  • Frequency Bands: 2x31, 1/3 octave, ISO spacing
  • Filter Type: Constant Q -3% center accuracy
  • Range: +/-6dB or +/-12dB selectable
  • Frequency Response: 20Hz - 20kHz, +/-0.5dB
  • Output Noise: -94dBm (unweighted)
  • THD + Noise: .01% (20Hz - 20kHz+10dBu)
  • Maximum Input Level: +22dBm
  • Maximum Output Level: +22dBm
  • Input Impedance: 20K Ohms typical
  • Power: 95?125VAC, 50/60Hz, 190-250VAC, 50Hz (Switchable)
  • Dimensions: DxWxH (in) 7 X 19 x 3.5
  • Dimensions: DxWxH (mm) 178 x 482 x 89
  • Weight: 13.5 lbs. (6.1 kg)

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Product Warranty Information

Art Audio
Tel: (401) 826-8286; Email:; Art Audio Website; 3 Years Parts and Labor with the exception of ART Microphones which are 2 Years Parts and Labor

  Product warrenty information

All instruments in our catalogs and on our shopping site carry the manufacturers' warranties against defects in parts and workmanship. Should a defect occur within the manufacturer's warranty period, contact us immediately.

We will be glad to help facilitate the repair or replacement as specified by the manufacturer. The manufacturer will determine whether the defect is covered under their warranty; we do not make that determination.

Please note: U.S.-based manufacturers WILL NOT honor warranties for items sold and shipped outside the U.S. Also, if a school, school district, or board of education purchases an instrument and resells it to an individual, the manufacturer considers the warranty to be void. Warranties are extended only to the original purchaser!

All warranties, stated or implied are held with the product manufacturer and they vary from item to item. Consult the documentation that came with your product for details in addition to the information below.
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ART is a company comprised of musicians, engineers and recording enthusiasts. Since its inception in 1984, we have been striving to redefine the performance versus price barrier with a series of innovative new audio products designed with the needs of the musician in mind.
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