Boss GT-100

Boss has been a major player in the multi-effects game for decades. So they’ve had a lot of time to research and deduce how to design a floorboard that combines versatility, tone, and ease of use. The GT-100 is the follow up to their popular GT-10 processor, but it’s much more than just a simple update from its previous model. All of Boss’s COSM amp and effect models have been completely redesigned and re-engineered from the ground up—along with new amp models—and the rig is driven by a new, higher-horsepower DSP chip that’s designed to replicate the nuances and tonal intricacies of the amps and effects that it models.

Simply put, there’s a lot going on underneath the GT-100’s hood. Each patch begins with one of 25 different amp models that range from the cleans of a vintage Fender Twin Reverb to warm leads influenced by the Mesa/Boogie Mark series and late ’60s Marshall Super Lead, and the raging drive of a Mesa/Boogie Dual Rectifier, Peavey EVH 5150, and Soldano SLO-100. Eight of the amp models are custom models built by the engineers at Boss, and serve up tones that the company claims are either difficult or impossible to achieve from standard tube amps—such as a high-gain stack model that smoothes out common uneven frequency response and a Marshall-influenced overdrive that’s been remodeled for more punch and smoothness. Each model can be combined with a chain of 51 effects, ranging from delays, reverbs, distortions and overdrives, modulators, and some pretty zany-sounding pitch shifters. What’s more, you can set up to 12 of these effects to run in any order before or after the amp model, and also split the signal into two separate feeds for thickening up the tone—essentially building a virtual dual-amp rig. Top this off with an easily accessible looper, dual-mode switching for both amps and effects, an assignable expression pedal, and a plethora of connection options—including USB in and out for direct recording and patch configuration—and the GT-100 adds up to a formidable recording and performance unit.

As intimidating as the GT-100 looks, I really had no issues getting to know the operating system and finding what I was looking for. This is, without a doubt, one of the easiest-to-use floorboard processors that I’ve come across in a long time. After connecting the unit to my iMac via USB and plugging in an Ibanez JS-1000, I started playing with the first bank of pre-programmed patches—which sounded good, if occasionally uninspiring. They are good stepping stones from which to work with the unit’s other features, however.

Figuring out how to immediately adjust the drive and EQ levels is a snap because Boss was smart enough to include them as immediately adjustable parameters from the pedal’s bright, dual LCD screens. If the amp model has a second channel, a turn of the assigned knob below the screen instantly flips you to the core settings of that channel, and it’s easy to save settings by simply tapping the WRITE button and setting the basic save parameters, such as the name, where you want to save it, or which patch you want to replace with it.

Setting the effects chain was a breeze, too. After pressing the EFFECT button, the dual screens light up with the chain on the left, and the selected effect’s settings on the right. I normally like to put my EQ pedal after the preamp, so all I had to do was twirl the knob underneath the word SELECT on the effects chain LCD until I found the EQ effect and turn the MOVE knob until the effect dropped itself to where I wanted it in the chain. It’s simple, efficient, and very little fuss.

Tone-wise, the GT-100 has its strengths and weaknesses. I found the mid-gain range of amp models to be more natural and full than the clean and blistering high-gain tones—unusual given how many modelers emulate the more extreme ends of the tonal spectrum best. Yet with the Ibanez and the GT-100, I had few issues dialing in fat, rounded overdrive with great body and definition—provided that I didn’t turn the gain levels up too high. The flip side is that nearly all of the amplifier modes and distortion emulations exhibited some woofiness and congestion when pushed hard. Thankfully there’s a workaround—setting up a dual-amp rig with less amounts of gain set for each one.


Tons of connection options. Great modulation effects and mid-gain tones. Reacts well to playing dynamics.

Clutter and congestion with more extreme distortion settings.


Playability/Ease of Use:




Roland Corporation

On the other end of the scale, I was able to coax some pretty nice cleans from the GT-100’s array of amp models, especially from the Vox AC30 and highly-accurate Roland JC-120 models. Each was fairly sensitive to changes from the guitar’s volume knob and reacted accordingly by smoothing out the highs and mids.

If you make extensive use of effects, the GT-100 is an absolute monster. Overdrives and boosts reacted accurately to most of the amp models—delivering more grit and drive and a rounded midrange. Modulation effects ranged from cool and conservative choruses to stunning, synthetic soundscapes (Seriously, try running a mix of the Slicer and Pitch Shifter into a ton of reverb. It’s amazingly ethereal). The heavier distortions and fuzz models sounded good when set more conservatively, but were rather difficult to keep defined at more aggressive settings.

The Verdict
Boss’s GT-100 is certainly a positive evolution of the GT-10. It has limitations—most notably if you’re a heavy player that uses a lot of extremely distorted settings. That limitation aside, it’s an immensely powerful tool for shaping your tone, has excellent mid-gain and clean tones and most importantly, reacts to your playing style and dynamic changes. And with the USB direct recording port and a myriad of connection options, and the GT-100 is one of the best options out there for the player who’s looking for everything-but-the-kitchen-sink recording and performance multi-effector without the mess and hassle of complicated switching and routing.