“If you’re looking to turn your guitar or bass into a completely different instrument, there’s no better way to do it than this”: Boss VG-800 V-Guitar Processor review

What is it?

Sitting at the cutting edge of guitar modelling technology, the Boss VG-800 is a system that can do everything from making a Strat sound like a Les Paul to transforming a Telecaster into a 12-string acoustic guitar. It’s a compact pedal that’s very pedalboard-friendly versus some of the previous guitar modelling efforts from Boss, but there are a couple of caveats.

The first is that unless you’re just interested in the amp and effects modelling, you’ll need to purchase the Boss GK-5 Divided Pickup or utilise the older Roland GK-3 with an adapter if you want to start making your guitar sound like a bass or using the alternate tunings. At around $270 new for the GK-5, that’s a significant extra outlay on top of an already pretty pricey pedal.

You’ll also need the Boss GK Serial cable to go from your pickup to the pedal itself, which adds $65-ish, so all in, you’re looking at over a grand to get a complete system. If you’re committed to dramatically changing the sound of your guitar, then you’re probably the sort that won’t be too worried about this - or the process of installing an additional pickup on your guitar. It’s not for everyone, though.

Specs

• Price: $714.99/£599/€685 (GK-5 pickup $274.99/£199)
• Type: Guitar/bass processor/synthesizer pedal
• Controls: 5x encoders, select encoder, output level, 3x footswitches, inst, effects, menu, left, right, exit
• Features: 150 memories, Modes: electric guitar, acoustic, dual guitar, electric bass, acoustic bass, dual bass, vio guitar, vio bass, synth,
• Connectivity: 1 x 1/4" (Guitar input), 2 x 1/4" (GK in, GK out), 2 x 1/4" TRS (Stereo FX loop), 2 x 1/8" TRS Type A (In, Out), 2 x 1/4" (R/Mono, L/Phones), 1 x 1/4" (CTL 2, 3/EXP 1), 1 x 1/4" (CTL 4, 5/EXP 2), 1 x USB-C (audio interface, midi)
• Bypass: Buffered
• Power: 9V DC power Supply, 690mA (included)
• Dimensions: 63 x 173 x 135mm
• Weight: 920
• Options: N/A
• Contact: Boss

Build quality

Build quality rating: ★★★★★

Like any Boss pedal I’ve encountered, the VG-800 is a robustly built bit of kit designed to be used on the road. The metal chassis is colored an attractive Azure blue, with the majority of the fascia being taken up by a screen. The screen is a monochrome graphic LCD at 256 x 80 resolution, which, while not as fancy as those on Neural DSP and Line 6 units, is nice and clear thanks to the backlight.

Beneath the screen, five endless encoders double as buttons for tweaking your settings, and just to the right of those, a ‘select’ encoder for navigating the menus. The output level is set by a master volume at the top right of the pedal, and beneath that, there are some additional buttons for changing effects, diving into menus, and some extra navigation functions.

The pedal is wedge-shaped on the bottom half to allow for easier pressing of the switches and hopefully keep wayward stomps away from the screen and controls. The two leftmost switches move up and down the preset list, while the right footswitch offers additional control, working as a latching or momentary switch depending on the preset.

It’s got a decent weight to it overall, and I find no weaknesses in the quality of the build as I inspect every inch of it. The knobs are all attached firmly, offering a notched turn for finely tweaking settings with excellent tactile control. It's that expected Boss-level build quality through and through.

Usability

Usability rating: ★★★★☆

To use the Boss VG-800, I start by installing the Boss GK-5 Divided Pickup onto the bridge plate of my trusty Telecaster. I approach it with some apprehension, but it turns out to be much easier than anticipated, and Boss includes all the tools you need to install on a variety of guitars, bar a cross-head screwdriver.

I start by lining it up with one of the thin spacers underneath to get it the requisite 1mm from the strings. I then have to take the strings off for the final installation, which is nicely timed as I’m due a change anyway. As well as being 1mm from the strings, Boss recommends the pickup be at least 15mm from the bridge, which is pretty much exactly the clearance I have between mine and the screw that attaches the bridge pickup to the bridge plate.

Using one of the thin strips of double-sided tape, I stick it down to my bridge plate, and the adhesive takes almost immediately. I go for fitting it the opposite way to the Boss instruction video, as I don’t want the cable running where my picking hand goes. I’m able to fit the output section of the pickup to my guitar strap end pin using the bracket that comes as part of the package.

All in with the string change and watching the instructional videos to ensure I’m doing it right, it takes me about an hour to get everything installed, the guitar tuned up, and ready to go. It's a relatively seamless process to get it attached, although there is the option to permanently drill it into your guitar, for which you’ll need a lot more experience in guitar modification.

One thing I wasn’t a fan of is the length of the cable from the pickup to the output section, if it was a little longer you’d be able to fit the output section to the back of your guitar rather than having it on the front, which could be appealing for those who don’t want a big black box sitting on their instrument. I do appreciate that making the cable longer than necessary could result in it getting in the way of installing at the front, though.

With that done, I use the GK Serial cable to connect it to the VG-800, and in turn, I run that into my UA audio interface in order to set up and test the initial sounds. The first thing I notice is that the tracking of the bass strings results in some crazy sounding ‘wobble’, and that some of the sounds that should have a bass guitar on the low strings are upside down, as I’ve installed the pickup opposite to how the videos show.

Downloading the manual, I’m guided through the process of setting up the pickup in the VG-800 settings menu to ensure the best performance. First, I change the sensitivity of the string detection, which I quickly realise is what’s causing that horrible wobble on the low strings; it's set way too high by default, so I reduce it dramatically. I then set the distance between the bridge and the pickup, and switch the orientation so those patches with bass guitar on the low strings are the right way up.

With this done, the performance of the pedal is much better, and I can start diving into the sounds properly. For a pedal that’s so complex technologically, it’s surprisingly easy to get started with. Banking up and down with the footswitches is intuitive enough, and you can double-press the left and middle switches together to access the onboard tuner. The encoders below the screen are labeled to show their actions, which include completely changing the sound of your instrument, alternate tunings, BPM, and level.

It’s pretty easy to make quick adjustments, and the additional CTL 1 footswitch allows you to adjust certain parameters, whether that’s adding effects into the mix or doing sound changes like bending notes. Actually creating patches, though? That’s something that’s much more easily done in the Boss Tone Studio App. It’s doable with the pedal, but there’s much turning and clicking of encoders to get there.

Sounds

Sounds rating: ★★★★☆

I initially set up the VG-800 going into my audio interface, sending the left and right outs to inputs 1 and 2. The GK pickup goes via the GK Serial Cable into the requisite input of the pedal, while my usual guitar jack output goes into the guitar input alongside. This means I get my dry guitar tone and the effected sound simultaneously. Scrolling through the presets, I quickly realise that this is quite undesirable for some of the tones that feature alternate tuning, but knocking the volume back on my guitar is a simple fix.

The preset sounds are varied, from subtle changes like making my Tele’s single coils sound like a humbucker, or entirely changing my guitar to a 12-string acoustic or sitar. It’s super fun just scrolling through the patches to see what’s available, and with each patch, a push of the CTL 1 button can add additional voices, distortion, modulation, or time-based effects into the mix.

It’s worth bearing in mind that the majority of these sounds already feature amp modelling, so if you’re running them into an actual guitar amp or an amp modeler, you’re going to need to switch them off; otherwise, you’ll get a very harsh, digital sound. While I think Boss’s effects modelling is second to none, I’ve generally found I prefer the amp tones of other companies better, and I especially like to use 3rd party IRs to get those proper, mix-ready tones.

There’s a massive variety of sounds available, and for each patch, you can change the input instrument, giving you oodles of sounds to choose from. The synth patches and classic GR-300 Lead setting are super fun, but the ones that blow me away are those acoustic guitar patches, especially the 12-string simulations. In an instant, I’m transported into the Mosquito Song by QOTSA, and yes, I’m even tempted to have a go at Hotel California; they sound that good.

I come across a distorted bass sound that’s unbelievably fat, Leslie organ tones, as well as some spacy, synthesizer-based tones, but I do find that I run out of sounds to try quite quickly. There are 60 built-in patches in total, but with a lot of these covering more typical guitar tones like stereo cleans, overdrive tones, and lead sounds, there’s not so much of the weird and wonderful stuff I was expecting when I unboxed it.

This is where the Tone Studio app comes into its own, allowing you to quickly and easily start creating tones, as well as downloading other user-created sounds from the Tone Exchange. The UI of the app will be familiar to anyone who has used amp modelling software, and here you can bypass the amp sims in favor of your own, tweak your input instrument, play with effects parameters, and set about creating some very bespoke sounds.

I find the tracking is fantastic overall, and during my time with it, it’s a very rare moment when anything goes wrong with the pickup detecting my strings. I can smash open chords, bend up two steps, hit pinch harmonics, and everything stays incredibly well behaved in the pitch tracking. It takes some tweaking to get it there, but once the pickup is set up right, it’s scary how well it adapts to being a bass guitar or acoustic.

Verdict

The most impressive part of using the Boss VG-800 is the functionality of the additional GK-5 pickup. It tracks the guitar strings so much better than I could’ve imagined, making it an easy job for the VG-800 to transform your guitar into a completely different instrument. It’s surprisingly easy to use, delivers excellent quality tones, and has more bells and whistles than you’ll know what to do with.

The other side of the coin is that it’s a hell of an investment once you total up the additional pickup and cable into the cost, and it requires a lot of setting up to get there. The pickup installation isn’t too bad if you’re going for the non-permanent option, but you will spend hours tweaking the settings of the pedal to get it perfect for your guitar and playing style. Considering the overall nerdiness of this guitar processing system, I guess that comes with the territory.

MusicRadar verdict: While there’s no doubting that the Boss VG-800 fills a very niche part of the guitar spectrum, it does so extremely well. It’s not cheap, especially when you factor in the cost of the pickup and specific cable required to make it work, but boy does it track the sound incredibly accurately once set up. If you’re looking to turn your guitar or bass into a completely different instrument, there’s no better way to do it than this.

Also try

Boss SY-200 - $329/£299/€305

If you don’t want the faff or expense of setting up an external pickup, the Boss SY-200 allows you to dramatically change the tone of your guitar without having to do anything other than stick it on your pedalboard. It’s got analog synths, strings, organs, and even some special SFX one shots built in, as well as a sequencer.

Read more: Boss SY-200 review

Boss GM-800 - $846.99/£589/€650

If you want to get deeper into making your guitar sound like an entirely different instrument, the Boss GM-800 is a powerful synth engine for your guitar. You’ll need an external pickup to use it like the VG-800, but it unlocks over 1,200 tones and even rhythm tones, making it a proper powerhouse for out-there guitar sounds.

Line 6 Variax - $/£Various

Although you can only find them used nowadays as they’ve not been in production since 2023, Line 6’s Variax is probably the closest guitar processing system that isn’t from Boss or Roland. It’s an electric guitar that utilises modelling tech to sound like any other guitar, whether that’s a Tele, Strat, Les Paul, or loads of other guitar models, as well as alternate tunings.

Read more: Line 6 Variax 600 review

Hands-on videos

Guitar World

Make Your Guitar Sound Like Any Other Guitar?! The Boss VG-800 blows our minds at NAMM 2025 - YouTube

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Brett Kingman

BOSS: VG-800 V-GUITAR Processor. How I'd Use It - YouTube

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Guitar Bonedo

Boss VG-800 | Next Generation Virtual Guitar Processor | Sound Demo - YouTube

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