Amp Up Part 2, The Powered Stage Monitor as Keyboard Amp

Most touring weekend warriors bring their own monitors to gigs so as to maintain a consistent and predictable onstage keyboard mix.
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by Eric Lawson and Tony Orant


Most touring weekend warriors bring their own monitors to gigs so as to maintain a consistent and predictable onstage keyboard mix. There are loads of options these days—everything from combo amps (see last month’s issue for four of the latest from Barbetta, Bose, Motion Sound, and Roland), to self-contained mini-P.A. systems, to the subject of this roundup: powered stage monitors.

Being P.A. speakers first and foremost, they’re meant to reproduce any type of sound with minimal coloration—that’s a lot like what we keyboardists are called upon to do with our workstations, clonewheel organs, and synths. Seeking the perfect balance of volume and fidelity for these diverse sound sources, while keeping things portable, is a tall order. Fortunately, it’s one that more products than ever have risen to fill.

My good friend and über-weekend warrior Tony Orant and I [Eric Lawson] joined forces to put a total of ten powered speakers through their paces onstage, at rehearsals, and at home. In alphabetical order, these were the Bag End PTA-1200R; Behringer B412DSP; JBL Eon 515; Mackie SRM450v2; M-Audio GSR12; QSC K8, K10, and K12; and Yamaha DSR-112 and MSR-250. On page 50, Tom Brislin, who’s toured with Yes, Meat Loaf, Renaissance, and his own band Spiraling, tries out a high-end entry from Italian maker FBT. Which ones came closest to the ultimate keyboard monitor? Let’s dive in and see.

The Schlep Factor

Many of our gigs—and yours, probably—involve bad weather, dark hallways, late nights, and some kind of ramp or elevator only if we’re lucky. Thus, weight and ease of transport are a key virtue of any gear. There was a three-way tie for welterweight champ between the JBL Eon 515, Yamaha MSR250, and QSC K10, all of which weigh under 32 pounds. I’ll give the edge to the JBL, considering it houses a 15" woofer and still keeps the weight down. Tony Orant, on the other hand, didn’t like the Eon’s odd shape. “Some of my gigs require an involved rig, so I try to minimize trips in and out,” he explained. “The JBL’s bean-like shape mandates that it stay face down on any stack of gear you’re rolling on a cart, or else it may wobble off. I usually end up taking it on a last trip by hand.”

Dual combo inputs (one of which can take a mic), RCA ins, separate unity-gain outputs, and a “post fader” mix out make the QSC K series flexible. The K8, K10, and K12 all have this rear panel in common.


The Behringer B412DSP was a beast to move at 65 pounds. Bag End wins the “most likely to withstand a tornado” award with the PTA-1200R, a small package that’s built like a tank. At just under 50 pounds, you know you’re carrying gear, but the size and simple square shape make it car-friendly. The M-Audio GSR12 is compact and light, with great lines and easy-to-grab handles on the top and sides. The overall rectangular shape, as contrasted to the rounded corners on the Mackie, Behringer, and JBL, makes it “compress” into your vehicle more easily

Weight is largely a factor of the materials that make the enclosure. For most of these speakers, that’s lightweight molded plastic. The Bag End PTA-1200R and Yamaha DSR-112 use wood and steel, conveying biker-like roadworthiness. “Don’t underestimate the durability of plastics,” chimed in Keyboard editor Stephen Fortner. “I’ve beat the crap out of my old-model Mackie SRM450 for years, sometimes literally throwing it into the van because I was tired and impatient after a gig. It’s gotten ugly, but it still works.”

Physical Design

All the speakers are shaped such that you can place them vertically or on the floor as wedges, except for the Bag End PTA-1200R, a rectangular box that really wants to be on top of a gear rack or speaker pole at ear level. The Bag End is dripping with boutique, hand-built quality: solid wood construction, a heavy speaker grill, and a nice spring-loaded handle on top. While heavier than it looks, it’s not that difficult to maneuver. Bag End does make an electronically identical version in a wedge shape, called the PTA-1200RF. So, you get one or the other.

The QSC K series and Yamaha DSR-112 are, in our opinion, the classiest looking speakers, both presenting a stealthy appearance onstage and creating the perfect angle to project sound directly at you. Looking like the love child of R2-D2 and a European kitchen appliance, the JBL Eon 515 has the most sci-fi contours. It’s great for wedge placement, but Tony noted that “it’s unstable if placed vertically on top of a ribbed rack box, such as those made by SKB.”

On Eric’s Gigs

I [Eric Lawson] used several of these speakers on gigs with my working cover band SoulerCoaster. I really enjoyed the fact that the Behringer B412DSP has a built-in two-channel mixer with separate volume knobs. Initially, I didn’t realize that the dual inputs were XLR only, so I was lucky to have direct boxes on hand to convert my 1/4" keyboard cables to XLR. It would be great if all powered monitors had XLR and 1/4" inputs, but though I wasn’t packing a compact mixer, many keyboardists with multisynth rigs do, and many such mixers have XLR outs.

The Behringer was impressive for volume and bass. It had all the headroom I needed to hear my ROMpler (a Yamaha S70XS) and clonewheel (a Nord Electro 3). While adjusting the EQ and volume knobs, I found myself scratching my arm on the cooling fins, which are the largest, sharpest, and most exposed of any of the speakers I tested. The Behringer had a more bass-heavy sound overall, not quite as defined and crisp as other speakers I used. It is only $300 street.


<-- Mackie SRM450v2.

The B412DSP compared quite closely to the Mackie SRM450v2, in both its physical design and its tight, compressed projection of sound. The Mackie was crisper and less boomy, not to mention easier to carry at 40 pounds. Mackie’s fit and finish was better than the Behringer’s, which is to be expected given the higher street price of $599. The Mackie takes only XLR cables and has just one input. Again, this is fine if you’re using a submixer with XLR outs.

Yamaha’s DSR-112 and QSC’s K10 and K12 had the rest of the speakers beat for power. These speakers sounded similar to one another, with a very well balanced blend of high, mid, and low—almost like hearing a perfectly mixed concert from a single speaker. I personally preferred the QSC, as it was easier to carry and had an incredibly quiet noise floor. The Yamaha had ever so slightly more audible background hiss. It has both XLR and 1/4" line inputs for its single channel.

The Bag End PTA-1200R’s monstrous output was quite a pleasant surprise, especially given its small size. This tight little package kicks out some major sound across the entire spectrum. Moog bass, drum loops, treble-range synth pads, and Wurly electric piano sounds were all punchy, crystal clear, and in-your-face. A pair of these could easily serve as a small P.A. system for a whole band.

The JBL Eon 515 also packs a surprising wallop for its small size. I pumped a heavy drum-and-bass groove through it and could feel the air emanating from its ports, as if I was standing inches in front of a real kick drum—cool. It bears repeating that though JBL is the only speaker in this roundup with a 15" woofer (most of the others are 12"), its weight is among the lightest. It also boasts enough submixing to be a borderline combo amp, with three channels: a single XLR input (mic or line switchable) plus two 1/4" inputs. The JBL projects similarly to the Mackie SRM450v2, but has a broader spread with deeper low end. By contrast, the Mackie has a more focused sound at the cost of capturing slightly narrower bandwidth on the low end.

Though M-Audio sent me two GSR12s, initially I evaluated just one as a mono monitor, since that’s what I’d done for the other speakers. In this context, it had the least headroom of the speakers tested, presumably due to its lower power specs. At lower volumes, though, its sound quality rivaled the Mackie. Given that the GSR12 is nine pounds lighter and typically $100 less out the door, that’s saying something.

When I broke out the second GSR12 to get a stereo mix going, my opinion improved further. I do several solo gigs a year for my office and neighborhood, and the M-Audio sounded very hi-fi in these settings, i.e. where I wasn’t competing with loud guitars and drums.

The GSR12 boasts a knob that selects four optimized EQ curves: live instruments, CD/iPod, DJ (increased low end) or microphone P.A. The differences are subtle, but it was cool to have this versatility. In particular, the DJ setting opened up the low end of the Yamaha S70XS bass and drum sounds, which I use as backing tracks for solo performance. These are also the perfect speakers for DJing a party from your iPod.


 <--The Mackie SRM450v2’s panel is bare-bones, but the XLR in does have sufficient gain to plug a mic straight in.

On Tony’s Gigs

I [Tony Orant] play with a number of different bands. I used Yamaha’s MSR250, one of the least powerful speakers in this roundup—at least by the numbers—over a six-month span for a recurring gig at a casino with a fairly tame rock band. The load-in at this venue is equivalent to four city blocks, and ends with 50 yards of travel across the gaming floor. I tapped into a monitor send and ran a full mix and my keyboards through the MSR250. With both 1/4" and XLR inputs, a mic/line switch, and two channels with independent level, bass, and treble controls, I was covered for any scenario. Vocals were clean and crisp, the acoustic guitar had a nice body, and my Yamaha S90ES piano patch sounded fantastic. It’s not a loud gig, but I still have to compete with a drum kit, bass rig, and two small guitar amps. Even though the MSR250 specs at just 250 watts, I never needed more of anything. I couldn’t have asked for a more perfect setup for that gig, especially at load-out.

<-- Yamaha DSR-112.


My tribute band Pink Freud plays with much more “rock” volume, so it demanded a higher-powered system; not surprisingly, this gig also involves the most elaborate of my keyboard rigs. I alternately used the QSC K10 and K12 (those model numbers correspond to woofer size), and Yamaha’s DSR-112 here. I really loved the QSC K12. Its tight but big low end, smooth highs, and well defined midrange make it one of the nicest sounding amps I’ve ever had. My Hammond XK1 organ (run through a Neo Instruments Ventilator rotary pedal) was mellow when needed and screamed when necessary, and yet my S90ES piano sounded fantastic through the same speaker, even at high volume when organ and piano were played together.

When I’d occasionally thump a Moog Taurus bass synth sound, the K12 easily supported the low end for the whole band while our bassist was picking the “tick-tock” at the beginning of Pink Floyd’s “Time.” I eventually (and at first, reluctantly) tried QSC’s smaller K10 in its place— and was completely won over. All my patches sounded killer through it, including my piano, and even the Taurus didn’t have that familiar flatulent sound of asking a woofer for more bass than it has to offer.

Though all three QSC models (K8, K10, and K12) have a 1,000- watt power rating and 1.75" compression tweeter in common, the K10 became the mainstay of my Pink Freud rig thanks to its smaller size and nine-pound difference. It sits floor-monitor style atop a pair of stacked SKB racks, and fills the whole stage—which hosts a drum kit, bass rig, and vintage Marshall 50-watt half stack that the guitarist leaves at 10—with keyboards. Minimoog and ARP String Ensemble emulations sound fantastic, and even my thick pads and washes from Spectrasonics Atmosphere are enormous . . . in mono, no less. After I switched to the K10 for keyboards, my drummer and I bought a pair of QSC powered subwoofers, and now use these along with the K12s as the band P.A. We do some gigs without the subs, using only the K12s up front, and they hold up amazingly well.

I also play with a variety rock band covering everything from Tom Petty to Lady Gaga. That band runs only vocals through their P.A., so my keyboard amp needs to fill the room. I take the supposed runt of the QSC litter, the K8, running just one cable from my S90ES, and I have plenty of power. Using a speaker stand, I elevate the K8 just over my head so as not to blister my ears, and every once in a while, I’ll be asked to turn down “a hair.” Like the K10 and 12, it boasts 1,000 watts, but I wouldn’t punish its 8" woofer with Taurus pedals at high volume. Everything else, including my benchmark S90ES piano sound, kills through it.

When the Yamaha DSR-112 arrived, I put it to use with Pink Freud and an ’80s “hair band” I play with. It performed spectacularly, easily filling the whole stage. The piano’s low end sounds great through it, and even running dense pads with high-gain effects won’t push it into clipping—I tried! That’s not surprising given the Yamaha’s 1,300 watts, 2" titanium tweeter, and 12" bass driver that seems to think it’s a 15". At 47 pounds, it’s a little heavy to lift to the top of an ear-level speaker stand or gear rack, but projected well when I placed it on my rack wedge style. Against not one but two guitarists playing ’80s rock through Marshall half stacks, the DSR can easily put the hurt on those guys. As the saying goes, “You don’t get tone on a diet,” and the DSR- 112 doesn’t disappoint.


<-- Yamaha’s DSR-112 panel is similar to the Mackie, but with a 1/4" input next to the XLR jack.


<-- The brand-new JBL Eon 515XT packs a real mini-mixer. The standard Eon 515’s panel is similar, except with a three-position EQ (flat, boost, and cut) in place of the XT’s bass and treble knobs.

I used the JBL Eon 515 for some of those gigs as well. I love its sound, but in a difference of opinion with my co-author Eric Lawson, my ears say it’s a bit underpowered for its size. It has great low end, and very pleasing mids and highs, but for me, it just never got quite loud enough. It’s built-in mixer makes it very flexible, and the three EQ Curves are useful for working in different rooms, though I found “flat” to work best most of the time. However, while I could “cheat” and get away with only a cable between my S90ES and the QSC K8, I had to insert a line mixer before the Eon for extra gain, and even then, I still wished for a little more headroom. I do use the JBL at home for band rehearsals (no Marshalls!), and with a mixer in front, vocals, keyboards, and guitars all sound great through it.

I used the M-Audio GSR12s with yet another band. Doing mainly late ’60s and ’70s rock covers, this is the loudest band I play with, so I put a pair on poles. The GSR12s did a good job with Wurly electric pianos with some grit on them, and handled most everything I gave them, but really shined with my Hammond XK1/Ventilator rig—they really seemed to suite the frequencies of the organ. I still ran in mono, but having two speakers gave me plenty of power—in this band, one wouldn’t have been enough. Since they weigh about 30 pounds each, carrying one in each hand is no problem.

<-- Behringer’s B412DSP doubles up on inputs, and both have mic-level gain if cranked up.


For me, the QSC K10 and Yamaha DSR-112 are the cream of this crop. Eric and I agree that they’re the most pleasing cosmetically, they’re the most roadworthy, and they sound amazing. You’ll appreciate the K10’s light weight at the end of the night. But if you need just a bit more brute power to punish a guitarist or two, the DSR-112 or QSC K12 might be your weapon of choice. Either model will do the job and do it right.

Powered speaker choices are abundant, with this article covering only a targeted selection. We favor the lighter-weight models—the QSC K10 in particular has a standout performance-to-pounds ratio. The Yamaha DSR-112 makes up for its greater weight with more punch still. The M-Audio GSR12 delivers hi-fi sound and bang-for-buck, but you’ll need two to compete in loud rock contexts. There were many similarities between the JBL Eon, Mackie, and M-Audio speakers, with Eric’s nod going to the JBL based on how it moved air.

New rule: Anything that might be used by keyboard players and that has XLR outs should have a ground lift switch built in. Except for the FBT HiMaxx, none of these speakers have one. The assumption seems to be that if you get ground buzz, you’ll lift the ground elsewhere—but it’d be nice not to have to carry direct boxes or those little XLR barrel lifts just for this purpose.

Speaker tone is perhaps second only to keyboard action for causing differences of opinion, so we recommend using this roundup as only one guide in your quest for the right powered stage monitor. The other two guides are your ears, and any speaker that made it into this article deserves to spend some quality time with them in the iso room of a music store. Then, take advantage of a good retailer’s trial period and try your top candidates on your gigs.


<--The M-Audio GSR12 has four preset EQ curves: Normal
(flat), Hi-Fi, DJ, and Voice.

FBT HiMaxx 40a

Made in Italy, the FBT HiMaxx 40a is housed in molded polypropylene, with a very powerful amp. Skeptics about how much bass and punch a 12" woofer can deliver will be floored at the tight, clear sound, which stays clean and grunge-free even at sound pressure levels that might run afoul of OSHA.


I used a pair of HiMaxxes as stage monitors at a theater concert for an audience of about 1,000. I dedicated the HiMaxx speakers to my synth setup, and set them behind me in wedge position. The program was music by the Who. Needless to say, drummers, guitarists, and bassists love to rise to the occasion of duplicating the sonic bombast of the epic rockers. No problem—my synths cut through the other instruments and stage noise loudly and clearly. Best of all, they sounded warm while never getting close to clipping.

Sure—loud is great, but what about fidelity at lower volumes? The HiMaxx 40a provided clean sound in intimate settings as well, and I wouldn’t hesitate to take it to a jazz gig. The three-band EQ helps if the room has problem acoustics, but I barely needed to touch it. Overall, the HiMaxx 40a gives you a completely uncolored reproduction of what you put into it, with seemingly endless headroom to spare. In fact, the HiMaxx calls to mind lofty pro touring monitors, more so than it does the typical “music store” powered wedge. Yes, it’s somewhat more expensive than the latter, but won’t set you back nearly as much as the former. Tom Brislin


Late-Breaking News


Here’s a Murphy’s Law of the magazine biz: The bigger the roundup, the more likely something new will show up right when we go to press. JBL’s Eon 515XT just hit at Winter NAMM 2011, so we couldn’t get units in time for a real-world workout. JBL says, “This enhanced Eon has increased input gain and new speaker voicing, and the SPL rating goes up from 129 to132dB. This probably addresses any volume concerns the reviewers had.” JBL is also sending us the PRX612M (shown), a 1,000-watt, 35-pound speaker that competes more directly with the QSC K12 and sells for about $700 street price.

We also just learned that Behringer discontinued the B412DSP, but the B415DSP (the same thing with a 15" woofer) is still made at press time. We intend to check out the B812 Neo, which boasts 1,200 watts and streets around $550. Closer (lower, in fact) to the B412DSP’s price is Samson’s Auro D412A at approximately $250.

We'll update this story when we've had time to put these new speakers through their paces in the real gigging world. --Stephen Fortner, Editor