An ideal result of precise market research is QSC’s GX7 addition to its GX Series of portable amplifiers, built specifically for those professional musicians and all various pro audio types who frequently use today’s most popular passive loudspeakers ranging in size from 12-and 15-inch 2-way cabinets, as well as many dual-woofer and subwoofer models.
Such inspiration for adding a new topshelf amp to the GX line — shared with me by QSC director of marketing communications Ray van Straten at the very conclusion of this review — supported my own findings after I most frequently paired the GX7 with two workhorse JBL MRX 512M stage monitors (passive, 12-inch, 800W program/1,600W peak rated) for nearly six months of various gigs of all types.
Both physically and in application, the 2-channel GX7 ($599 street U.S.) is quite comparable with the GX5 that I reviewed for PAR in 2008. These Class-H power amplifiers look nearly identical sitting next to each other, yet the GX7 significantly varies upon its output section, which features a design based largely on QSC’s PowerLight technology. This is a step up from the GX5 in several ways: most significantly, increased power output while simultaneously decreasing overall weight. The GX7 is a featherweight 15.5 lbs., quite a weight savings compared to the heavier (but still highly manageable) GX3 and GX5 at 27 and 28 lbs. respectively.
On the rear panel, I/O options include two XLR, quarter-inch TRS and phono/RCA inputs per channel; and two Speakon combo and binding post outputs. Also included is sub/satellite 100 Hz crossover control point, a switch that toggles between full-range operation and a Channel 1 LF pass-thru/Channel 2 HF pass-thru.
At 8 ohms/1 kHz (both channels driven), the GX7 provides 725W of power (the GX3 and GX5 provide 300W and 500W at the same specification, respectively).
Worth noting, QSC includes its GuardRail technology in the GX Series—that “automatically takes into account all variables of load impedance, AC voltage, and power supply dynamics” to protect both amplifier and speaker from damaging overload—great for those of us who like to “set it and forget it.” More specifications of the GX line are available at the QSC website.
The GX7 did at least a dozen different gigs with me, providing power for the aforementioned JBL MRX 512M pair as both stage monitors for bigger club gigs and main PA for smaller ones. I also used it in crossover mode when playing a venue with a passive house subwoofer. In every case, the experience was straightforward and more than pleasant. Even pushed to the near max, the GX7 provided plenty of headroom and stayed clean before the onset of any audible distortion. Both players and commenting venue employees praised the loud but sparkling-clean sound (so the right people were happy). With each gig, I felt that I was getting full aural potential from my beloved MRX 512M pair.
For one rehearsal, I set up the previously reviewed GX5 for left-side monitor power, and the GX7 for right. The extra 200-plus watts really made a difference for everyone in earshot. If I were going for a GX amp today, I would most likely spring for the GX7 as for a relatively nominal upcharge over the GX5, it is overall more useful, simply based on its increased output (and decreased weight).
According to company research, a majority percentage of potential GX7 users would find its feature set and specifications meeting or exceeding their needs and expectations. I fully believe that, as I regularly witness gig after gig in which the GX Series would provide the clean, reliable power needed to get the job done, with no hassles or complicated interface. And in my experience, I found that QSC wisely provided what the majority of passive loudspeaker users truly need, and in making the decision not to add more advanced options (also adding cost), were able to focus on power and fidelity – the very things one buys a power amplifier for.
In my original GX5 review, I said, “It is not only a good choice for the full-time live-sound professional, it is also an ideal choice for the budget-restricted gigging musician who often runs his own sound, and/or lugs his own monitoring rig to clubs, and much more.” Considering its high power vs. low weight specs and QSC pedigree, this statement may be even more applicable to the GX7.
Price: $699 list
Contact: QSC Audio Products | qscaudio.com
Strother Bullins is the editor of Pro Audio Review.