I love it...

I use this exclusively. I run a UniVibe and a Fuzz in front and go straight in the front of my amp. By using pedals in the front it frees the processor up for more effects. I have settings for all the different bands I play with so I can have individual sounds. I use it for a blues band and get a really sweet Plexi sound, and I also use it with my acoustic trio. Running it clean makes the acoustic bright and clear. I love it and wouldnt consider using anything else. I love the Tera Echo effect. I have an actual MO2 pedal and its a bit different than the MO2 effect, but very close. I have it set up with AB switching, to go from a Fender Twin amp to a Marshall Plexi amp and I run through a Marshall Origin 20 head or a Marshall DSL 40c. When I use it for my acoustic trio I run it straight into the PA. It sounds awesome. I hate have a messy board full of pedals and cables, this is clutter free and easy to set up. The best part of this is the MASTER VOLUME on the board. I can run my amps hot and turn the board down to 2 or 3 and it sounds awesome. Best processor I have ever used. The most realistic effects out there.

Almost there...

I recently acquired the GT-100 with a view to simplifying my live rig.

To date, I've been using a BOSS ME-50 for tone shaping and occasional effects like a distortion, tremolo and octave/whammy function, into a Line 6 M13 for reverse delay, chorus, flanger, other tremolo effects and some really out there filters and synths. With the patch switching for my Line 6 Bogner Spider Valve 212 (clean with delay and reverb, crunch, lead), it was getting tricky to achieve all of the simultaneous changes I wanted to make without disrupting my performance, and it was also taking far too long to set up for rehearsals, recording sessions and shows alike.

On paper, the GT-100 allows me to ditch the other three pedal boards (I'll still use a vocal effects pedal too), but whilst I'm getting close, I haven't quite replicated all of the sounds I need for the band's full repertoire yet. Part of the reason is the fact that there's so much choice, and it's very easy to lose oneself in fiddling with parameters (to that end, it's very much the "studio at your feet" that Johnny Marr refers to it as) with a view to bettering legacy sounds when it's proving difficult simply to reproduce them.

The filter and synth aspects are also not at immediately usable as those on the M13, and at the time of writing I fear that I may in fact need to retain that unit (or swap it out for an M5 or something) to avoid disappointing fans (and indeed myself) wanting to hear something close to the sound of recorded versions of songs that have been released.

Another practical element to consider when moving from separate stompboxes or something like the M13, is the lack of colours to tell you what you're using / what's switched on and what's switched off. There are LCD view options that kind of do the same thing, but it's all in a very functional burnt orange that makes it hard to distinguish between delays, modulations and so on.

However, the unit is very easy to use, and I think once I also switch to a more responsive all-valve amp (having tried one, I'm 99% sure it will be the Fender Hot Rod Deluxe III), then I think the issues I've had maintaining the right balance within the overall band mix (sometimes was too trebly and sometimes way too muddy), things will settle down. The clean channel I'm using on the Spider Valve feels a little bit stiff, like it won't be driven by additional gain pumping through the GT-100 when distortions are engaged.

Fundamentally, for practical reasons, I've done the right thing, but it's thrown the cat amongst the pigeons, and the transition is a little frustrating at times, especially for my bandmates who wait patiently for me to twiddle knobs for minutes that feel like hours in between short bursts of verses and choruses etc.!

What's great, is that it will allow me to have different settings for each and every song (time-based effects can be set to a specific tempo), and whereas the settings I'd programmed for the Spider Valve often found my guitar overpowering the live mix (the amp is either "off" or "bloody loud"), the GT-100 gives me lots more control.

all I need

This has been the best purchase of equipment I have ever made. My favorite thing about this is how I can lay out my pedal chain exactly how I want it. I love that I can assign the buttons to the effect pedal. It allows two major effects, and you can place them anywhere in the chain. It allows for compressor, od/dist, foot pedal, wah, eq, noise suppressors x 2, delay, chorus, and reverb. There are so many choices for the two effects patches per channel. I use this with the four cable method, and split my chain into front of amp and send and return. I have used this processor with the amp modeling and was very impressed, but mainly I turn off the amp modeling and use my Marshalls drive. The Boss processor has a better live sound than I have heard from the Line 6 boards. And their are advantages with it being Boss, they include the MO2 and Tera Echo effects. My only issue is the difficulty in assigning functions to pedals. It takes a lot of reading and watching youtube videos to figure it out. Ive owned this from the day it was released and used it on hundreds of gigs. Its tough and never had an issue.

Preferred Settings + Usage:

From Gear Setup

More of everything.

The BOSS GT-100 was a replacement for my GT-6 (that got lost and found again). While the GT-6 has its focus on the basic stomps the GT-100 expands to way more playful sound manipulation. More effects, more options, more controls. The amping section was improved a bit but couldn’t convince me but I used this one in 4-cable-method anyway. The only thing that is a step back from the GT-6 is the expression pedal that does not work as finely as before but feels a bit “steppy”. Otherwise as with all BOSS-equipment indestructible and the soundquality is very good. So when you’re looking for a compact way to replace a big collection of stompboxes, this is the way to go.

Great board!

This does everything I want it to do. I play bass, acoustic guitar and of course my electric, I benn using it for years in a fairly large church worship setting.

Boss GT-100 V2 Good Sounds by Pre/Amps FX and COSM technology plus MIDI

Great sounds not better than the Line6 HD POD 500X but EQs are the great point of comparison with the Line 6, you don't need a guitar amp, I use it with two power ampsof 2 x 400 w, and speakers used for music, but not guitar amps, and it sounds really great when patch settings are adequate.

Solves all my problems!

With this setup, i can play a lot of music styles, in a miked amp or pluging it on a mixer direct to PA. Sounds great!

Multi effect with charming amps simulations

the best about it are those nice distortions and overdrives, the other effects are ok but nothing special about them. the wah-pedal and distortion sound awesome on synths.

Awesome

I had the former GT10, and this is a huge improvement all around. Sounds great.

Great use for pedal multieffects

I use my GT-100 mostly for guitar effects. I don't really use the Amps that much because i plug it into my amp with effects loop.