GXD Series power amplifier — 400W x 2 at 8 ohms (non-bridgeable)
Our take on the QSC GXD4 by Crutchfield's Dave Delamere
Power up your gig
No matter the type of venue, you need an amp that'll give you plenty of clean power for your music without breaking your back or your wallet. QSC designed the GXD Series amps to deliver ample power to work with the most widely used loudspeakers in the music industry. Its built-in DSP (digital signal processing) lets you adjust for any type of loudspeakers in your setup. Front-panel controls give you quick access to its gain levels and equalization, so you can adjust your stage settings on the fly.
Strong and safe
The GXD4 2-channel amplifier pumps out 400 watts per channel at 8 ohms and 600 watts per channel at 4 ohms. Its class D design and digital limiter ensure that you get maximum output, while still protecting your speakers from being overdriven. This amp includes high- and low-pass crossovers, a 4-band parametric EQ, and signal alignment delay settings, along with 20 presets to give you a starting point to help match your speakers to the amp.
Connections and control
Front-panel controls provide precise gain and DSP adjustments, while the LCD display helps with your amp setup and status. LED indicators keep you aware of signal, input overload, and amp clipping. The GXD4 also offers combination XLR and 1/4" TRS input connectors for your source material, as well as binding posts and NL4 connectors for your speaker cables.
- 2-channel power amplifier
- power output:
- 400 watts RMS per channel at 8 ohms
- 600 watts RMS per channel at 4 ohms
- frequency response: 20-20,000 Hz (+0.7 dB, -0.8 dB)
- signal-to-noise ratio: 100 dB
- total harmonic distortion: <1.0% (1 kHz)
- rotary encoder knobs for gain and DSP parameter control
- DSP includes high and low-pass filters, 4-band parameteric EQ, limiting, and delay
- digital limiting protects amp from overheating and overdriving
- RF, DC voltage, short circuit, and thermal protection
- front-panel LEDs indicate signal presence, clipping, and input overload
- integrated rack mount ears
- inputs: balanced XLR and 1/4" TRS
- outputs: binding posts and NL4 connectors
- dimensions: 19"W x 3-1/2"H x 10-1/4"D (2 rack spaces)
- weight: 11.3 lbs.
- warranty: 3 years
- Our 60-day money-back guarantee
What's in the Box:
- 2-Channel power amplifier
- 5' AC power cord (3-prong IEC)
- Quick Start Guide
- Warranty Registration information
Features and Specs
|Number of Channels||2|
|Watts per channel 8 ohms||400|
|Watts per channel 4 ohms||600|
|Watts per channel 2 ohms||---|
|Filters||Hi- / Lo-pass|
Overview: The QSC GXD series of 2-channel amplifiers are optimized for 8 and 4 ohm speaker loads, and feature special tunings to maximize the performance of the QSC E Series loudspeakers. The amps have a Class D output stage, digital signal processing, high- and low-pass filters, and digital limiting. The GXD 4 is designed to be rack-mounted and takes up 2 RU (rack units).
Power Output: The GXD 4 amplifier's output power is rated as follows in stereo mode, both channels driven:
- 8Ω Continuous: 400 watts
- 4Ω Continuous: 600 watts
- 8Ω Dynamic: 600 watts
- 4Ω Dynamic: 800 watts
Inputs: The GXD 4 features a pair of balanced XLR inputs and a pair of 1/4" jacks that will accept either balanced TRS or unbalanced TS inputs. The balanced inputs can be used for long or short runs, while the unbalanced inputs should only be used for short runs. The XLR and TRS jacks are connected internally and provide feed-thru to the other connector.
Speaker Outputs: The GXD 4 is equipped with a pair of professional NL4 speaker terminals and two pairs of binding post speaker terminals for mono and bi-amp speaker connectivity.
Independent Gain Controls: The GXD series amplifier offers independent rotary gain controls for Channel 1 and Channel 2. The gain controls provide precise setting and matching of sensitivity.
Digital Signal Processing: The GXD 4 features Digital Signal Processing with a 2.12" x 1" LCD display with 256 x 128 pixel resolution. The DSP can be set as Stereo DSP with changes being made to both channels simultaneously, or DSP A & DSP B with changes being made to each channel independently (except for Input Sensitivity). The DSP controls include:
- High Pass Filter (4th order Linkwitz-Riley), adjustable frequency 20 Hz to 4 kHz
- Low Pass Filter (4th order Linkwitz-Riley), adjustable frequency 60 Hz to 4 kHz
- PEQ (Parametric EQ): 4-bands with variable frequency, gain, and bandwidth
- Delay: up to 50 msec
- Limiter: peak limiter with power, aggressiveness, and impedance selection
Presets: The amplifier features presets that can be used for configuring the output to suit the loudspeaker type:
|Loudspeaker Type||DSP Type||High-Pass Filter||Low-Pass Filter|
|Full Range Satellite||Stereo||20Hz, 80Hz, 90Hz, 100Hz||Bypass|
|Subwoofer||Stereo||20Hz||80Hz, 90Hz, 100Hz|
|Monitor||DSP A |
|60Hz, 80Hz, 100Hz||Bypass|
|60Hz, 80Hz, 100Hz||Bypass|
|Subwoofer + Full Range Satellite||DSP A||20Hz||80Hz, 90Hz, 100Hz|
|DSP B||80Hz, 90Hz, 100Hz||Bypass|
|Bi-amp||DSP A||20Hz||1000Hz, 1100Hz, 1200Hz, 1300Hz, 1500Hz|
|DSP B||1000Hz, 1100Hz, 1200Hz, 1300Hz, 1500Hz||Bypass|
|Mono Full Range Satellites||Stereo||50Hz, 100Hz||Bypass|
Front-Panel LEDs: The front panel features the following LED indicators: 2 Green Signal LEDs to indicate signal presence, 2 Red A/D Clip LEDs indicate input over-drive and/or amplifier current clipping, and a Blue Power LED ring around the power button to indicate power is on.
Cooling Fan/Ventilation: The amp features an internal fan to move air through the chassis and out of its front- and rear-panel vents to reduce internal temperatures. The fan has a variable speed that increases or decreases based on the amount of usage.
Protection: The GXD 4 has protection circuitry against short circuits, open circuits, thermal, RF, and DC faults.
- Frequency Response: 20Hz - 20kHz (+0.7 dB, -0,8 dB)
- Distortion: < 1% THD
- Maximum Input Level: +23.5 dBu
- Signal-to-Noise Ratio: 100 dB (A-weighted, 20Hz-20kHz)
- Input Sensitivity: 1.2 VRMS, 3.9VRMS
- Voltage Gain (8Ω): 33.5 dB
- Dynamic Headroom: 1.25 dB
- Damping Factor: 100
- Input Impedance: 20k (balanced), 10k (unbalanced)
- Dimensions: 18.9375" W x 3.492" H x 10.18" D
- Weight: 11.3 pounds
Our Product Research Team
At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.
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