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Mesa/Boogie M3 Carbine Bass Amp Head Review

Mesa/Boogie M3 Carbine Bass Amp Head Review

The 300-watt/4-ohm, solid-state/ tube hybrid M3 is the latest addition to the company’s Carbine series, which includes the 600- watt M6 and the 900-watt M9.

Download Example 1
Straight to the DI: Recorded with a ’78 Fender Jazz, with Master Volume at 9 o’clock, Gain at 1 o’clock, and the other controls “flat”
Download Example 2
Pushing the limits of tube distortion on the Mesa/Boogie: Recorded with a ’78 Fender Jazz, with Master Volume at 8 o’clock, Gain at 3 o’clock, Bass at 10 o’clock, Mid at noon, and Treble at 4 o’clock (almost all the way on).
Fans of Mesa/Boogie’s guitar amps might be surprised to learn that the first amp the Petaluma, California, manufacturer built—way back in 1969—was made for bass. In the years since then, Mesa products such as the highly desirable (but discontinued) 400+ have embodied the company’s quest for bass-tone perfection. And their current offerings, which range in size from the WalkAbout to the Big Block Titan V12, have attracted a long list of players such as John Myung of Dream Theater, Ozzy Osbourne bassist Blasko, and Korn’s Fieldy.

The 300-watt/4-ohm, solid-state/ tube hybrid M3 is the latest addition to the company’s Carbine series, which includes the 600- watt M6 and the 900-watt M9. Besides being less powerful than its older brothers, the M3 has far fewer controls, but simplicity is part of its charm. And with paired with the Mesa Boogie Powerhouse 4x10 cabinet—a beast that can handle 600 watts at 8 or 4 ohms and comes with its own tone-shaping options—the M3 is a formidable and affordable head-and-cabinet package.

Simple Head, Hefty Cab
Our test M3 arrived unracked, and my first impression is that this unit is built to last. Plugging it in and flipping on the sturdy power switch illuminates an LED that’s bright enough to see under stage lights. Control knobs are big and easy to read, and the simplicity of the front panel is a plus, too. There are only five knobs: Gain, Bass, Mid, Treble, DI Level, and Master Volume. Everything else— the fuse, two 1/4" speaker output jacks, an effects send/return section with a bypass switch, the line out, a tuner output, a mute pedal input, and a ground lift—lives on the back panel.

Three of the front panel’s knobs do double duty. When I wanted less-focused tube bass tone, pulling the Bass knob (“Pull Deep,” Mesa calls it) delivered a more sprawling bottom end, and as I turned the knob clockwise, the sound inched into über-fat, synth-bass territory. Pulling the DI Level knob sends a flat DI signal that is unaffected by front-panel EQ tweaks. When I switched basses, I could mute the amp by popping out the Volume knob (“Pull Mute”). Very handy.

When I realized I wouldn’t have any gigs that required a 4x10 cab before deadline (my regular amp is a powered 1x12), I asked my friend Zach to use the M3 rig for a show he and his five-piece band were playing at a 450-seat rock club. He happily obliged, and after the gig, I took notes as we tweaked knobs and played a closetful of basses through the M3 and the Powerhouse.

Looking back, Zach acknowledged that the 96-pound Powerhouse had been tough to carry (his regular 4x10 is 23 pounds lighter), though the removable wheels and recessed metal handles did help. He used an active Manson John Paul Jones 4-string at the show, and he described the sound as stronger and more detailed than his usual active 4-string and 4x10 setup. In fact, Zach’s drummer felt that the rig came on a bit too strong for the band’s indie-rock sound. Offstage, however, the Mesa stack was a hit: The soundman remarked that the M3’s DI tone was better than most, and fans raved about Zach’s upfront, distinctive tone that night.

In Your Face
As I plugged in other basses, it became clear that unlike many tube-equipped amps that specialize in sounding wide and warm, the M3—with help from the Powerhouse—kicks out a more focused tone, even with the controls set flat. Fast lines and Victor Wooten-style thumb acrobatics came through nice and clear on an active ’78 Fender Jazz with Bartolini pickups, but the M3’s tube preamp helped keep things round. A fretless Ampeg AMUB-1 with old groundwounds was instantly capable of dub-worthy and electric upright tones.

The M3’s EQ controls made it easy to take advantage of the many sonic facets of stock ’61 Precision and ’62 Jazz Basses. Even when dimed, the M3’s passive, boost-only Mid control never got nasal or pointed. Cranking the active Treble knob while playing upper-register chords and double-stops did result in some harsh highs. But overall, it was easy to get detailed tones without sacrificing warmth—whether working with a tight rock sound on the flatwound-strung P-Bass to a variety of slap tones on the ’78 Jazz Bass.

An active Wal 4-string tuned B–E–A–D sounded rich and massive. This Mesa setup had no problem with B strings, and a 34"- scale Sound Trade 5-string with a vintage Jazz vibe sounded full and authoritative all the way down to the open B—even when I soloed the back pickup.

One of the advantages of playing through a tube preamp, of course, is having the ability to achieve musical-sounding overdrive. At first, I was slightly alarmed at how often the “input clip” LED lit up, but the manual assured us that this didn’t necessarily mean I was driving the amp too hard. Soon, I was turning down the Master Volume and turning up the Gain to overdrive the M3’s single 12AX7 tube for some excellent organic tube distortion.

Finally, I set the M3’s controls flat and explored the options on the back of the Powerhouse 4x10. Tweaking the “L-Pad” tweeter attenuator and 3-position crossover frequency switch—which included settings for 3 kHz (“Bright”), 4 kHz (“Sheen”), and 5 kHz (“Normal”)—was surprisingly effective. The 5 kHz setting was indeed “normal,” but 4 kHz with the L-Pad at noon and 3 kHz with no tweeter presented two intriguing variations. The M3 is also available as part of a 1x12 combo, but for louder gigs, it’s hard to beat a Powerhouse.

The Verdict
The $899 M3 Carbine is a straightforward, tube/solid-state hybrid with old-school warmth, modern punch, and plenty of power. It’d be great if the $1099 Powerhouse 4x10 was a tad lighter, but the tandem sounds wonderful and the M3 is easy to dial in for almost any performance situation. Together, they’re a match made in modern rock-bass heaven.

Buy if...
you don’t want to choose between tube goodness and aggressive clarity.
Skip if...
you need more power or surgical tone-sculpting options.

Street $899 - Mesa/Boogie -