Positive Grid Spark review: A smart game-changer for guitarists

Digital might be a four-letter word in the guitar world, but amp and effects emulation is nothing new; it’s been around for some time and it’s had a chance to get really good.

Californian company Positive Grid has been around since 2013, and has built a solid reputation around its BIAS FX and BIAS AMP software plugins, which perform incredibly detailed modeling of a huge range of amplifiers, cabinets and effects to make it sound like you’re playing through monster multi-channel rigs, even when you’re just plugged into your PC.

The Spark “smart amp” takes a bunch of Positive Grid’s digital amp and effects modeling expertise and distils it into one of the most amazing little practice amps on the market. It’s a small, simple, 5.2-kg (11.5-lb), attractively retro-looking box sized to sit on a bookshelf or desk, and it gives you the ability to let rip through literally thousands of different setups, even some that cater for bass and acoustic guitar players.

The top of the Spark offers a series of knobs and some buttons – most of these are overridden by commands in the app when you're connected to a device
The top of the Spark offers a series of knobs and some buttons – most of these are overridden by commands in the app when you’re connected to a device

Positive Grid

It may only be a 40-watt system, but make no mistake: the Spark is loud as hell. Its two small 4-in full-range stereo speakers deliver a pretty fearsome punch, including arguably too much bottom end – we’ll get to that in a minute – but it delivers volume levels that shake the walls at 70 percent on the dial, which is far more than you need in your bedroom and enough realistically to take to some jam and rehearsal situations.

The Spark comes with seven sounds built in, with familiar-looking knobs for gain, EQ, master and output volumes, as well as reverb, delay and modulation effects. It’s got a tap tempo button on top, a built-in tuner, a headphone jack, four customizable presets and another volume knob solely for music that’s coming out of your device.

Connecting your phone or tablet turns the Spark into an absolute ball-tearer of a Bluetooth speaker, and indeed one you can play right along with on your own guitar. But it also lets you open up the Spark app and unlock the stuff that makes this little amp so special.

Ten thousand tones and counting

For starters, you can download a multitude of sounds, free, from the Spark database. If you’re learning a song, chances are somebody’s taken a crack at designing the perfect sound for that very tune and uploading it for you to play with. Every one of these tones, plus all the ones built into the amp, are customizable as a full signal chain, and you can save them to the amp so you don’t need your phone connected to enjoy them.

Now, since any fool can upload sounds to the “Tone Cloud,” there is a ton of complete junk in there. Positive Grid can definitely do a better job helping people sort the wheat from the chaff here. On the other hand, as they say, quantity has a quality all of its own. Searching for John Mayer, David Gilmour, Van Halen, Hendrix, or my personal guitar god of choice, Nuno Bettencourt, will bring up dozens, sometimes hundreds of options, often representing different eras in an artist’s recording history, or indeed specific songs as mentioned above.

A neat device on its own, the Spark becomes a massively flexible library of tones, backing tracks and learning tools when connected to the Spark app
A neat device on its own, the Spark becomes a massively flexible library of tones, backing tracks and learning tools when connected to the Spark app

Positive Grid

If you roll your sleeves up and get under the hood, each sound can use one of 30 different amp models from the BIAS world, many designed to emulate famous real-world amp setups. There are 40 different effects pedals, and you can use one in each of the following categories: noise gates, compressors and drive pedals before the amp, and modulation pedals, delays and reverbs after the amp. Each of these amps and pedals have their own row of knobs and switches, so the range of possible sound options is absolutely colossal – but it’s all arranged in a very pretty graphical interface that will look very familiar to guitarists.

I’m only a beginner guitarist, so they’re not that familiar to me. As a drummer and a singer, I’ve always had one or two fantastic guitarists around to handle this stuff. But the pandemic has launched a thousand new stay-at-home hobbies, and figuring out some guitar has been one of mine. Even as a novice with no idea what each of these amps are supposed to represent, I’ve had no trouble working my way through the effects to find great sounds and tweak them to my liking.

Personally, I’ve been surprised and delighted at how good this thing can make my crappy playing sound without needing to trawl the music and second-hand shops and get a pedal board together. As somebody new to the game, the Spark has let me completely sidestep the gear acquisition syndrome stage (for the moment) and get pretty much any sound I can dream of, shy of harmonizers, whammy pedals and talk boxes, in minutes, piggybacking off somebody else’s hard work. Folks, that rules.

Oh, and because the Spark uses full-range speakers along with its amp modeling, you’ve got access to a bunch of crystal-clear acoustic sounds you couldn’t get through a regular electric guitar amp.

The Spark is a ridiculously flexible smart guitar amp with instant, free access to more than 10,000 different tones, using Positive Grid's excellent amp and effects chain emulators
The Spark is a ridiculously flexible smart guitar amp with instant, free access to more than 10,000 different tones, using Positive Grid’s excellent amp and effects chain emulators

Positive Grid

Jam tracks, smart jam and auto chords

The Spark is a practice amp, and it’s dedicated to helping you practice. As such, it plugs you into a huge free library of songs to play along with, many being original recordings with the guitar tracks removed – and a lot of these let you hit a button to grab a specific guitar sound right off the shelf to play along with, with the app showing you the chords all the way. You can slow it down, or loop a section to get it right before ripping in at full speed.

Then there are jam tracks designed to help you learn how to get around the fretboard in particular modes, and others you can go a little more freestyle over, in a wide range of styles from funk, reggae and fusion to pop, rock, metal and country. I’ve found these a super relaxing way to noodle about in the evenings.

Then there’s the Smart Jam feature, which lets you set a tempo and then play something in. The Spark analyzes what you’re playing, typically pretty accurately, and auto-generates drum and bass tracks for you to play along with. I’ve found this less handy; I’m not vibing with those auto-drummers.

And finally, there’s the ability to play along to songs straight out of Apple Music or Spotify – if the Spark “knows” the song, it’ll put the video on, and put up the chords so you can learn it. If it hasn’t seen the song before, it’ll sit there and analyze it for a few minutes, and then put the chords up for you. Now, don’t expect it to generate spot-on tab, but in many cases the chords are pretty accurate, and enough to get you going.

I have to admit, I didn’t expect to use this part of the Spark app much, but I’m finding it very helpful and a ton of fun.

On the back: a Bluetooth light, aux in, USB out and power plug
On the back: a Bluetooth light, aux in, USB out and power plug

Positive Grid

The Spark as a recording interface

Everyone can be a recording artist these days; it’s never been easier, and the Spark has a simple USB connection that lets you use it as an audio interface for your computer. Not only does that mean you can play your Spark tones straight into your Digital Audio Workstation (DAW) software, it also means you can listen to what you’re working on through this little powerhouse of an audio system, in lieu of a set of studio monitors.

A lot of people may never use this neat little feature, but others will absolutely love it for its convenience.

What the Spark Amp can do better in version 2

This is an insanely impressive device, but there are some clear places Positive Grid can tweak things to make the next version even better. For starters, the overall sound is pretty much universally recognized as being too bass-heavy. That means your choggy metal mutes will punch you right in the guts and sound amazing, but you do lose articulation up in the higher strings.

You can go and painstakingly edit all your amp sounds to EQ the low end down, which helps a bit, but what many Spark owners do is literally pull the front off, take one of the speakers out, and pack a bit of sound-absorbing foam in along the cabinet floor and up the back to interfere with the bass reflex port and soak some sound up. That’s what I did with mine, and when you put it all back together it’s definitely a more controlled sound, losing messy boom without losing punch. My guess is that won’t be necessary when we start seeing the Spark Version 2.

Secondly, there’s no ability to connect a pedal, which means that if you want to switch between sounds, you have to use your hands. That’s fine for practice, but in a jam or a rehearsal, a stomp box would be great. Even better if it had a tilt pedal for volume, wah and effects controls, and better still if it could handle some looping. I think there’d be a great market for pedal accessories for this amp; they wouldn’t necessarily have to be included. But right now there’s no way to do any of it shy of hacking into the wiring, and that seems like a lost opportunity.

Another thing I’d love to see is a built-in battery. It’s small and light enough that I’d love to be able to take it places without having to plug in, and it’s a pity you can’t stick it out in the back yard, download a “Sweet Child of Mine” tone and make friends with the neighbors … let alone how good it would be simply as a portable Bluetooth party boombox.

Additionally, while it’s nice having a headphone jack, I’d like to see a second Bluetooth connection built in so you can rock out in wireless headphones. Bluetooth headphones and earbuds are very much the standard these days, and I think Positive Grid should cater to people that use them.

Hey Positive Grid, can we get rid of the guitar lead next time?
Hey Positive Grid, can we get rid of the guitar lead next time?

Positive Grid

And finally, looking right down the wish list, there’s one part of using the Spark amp that feels far less 21st century than the rest of it: plugging in a guitar lead. Guitar leads twist and deteriorate and get buzzy, people trip over them, they restrict your movement, catch on things and mess up your room. There are heaps of perfectly decent short and medium range wireless systems available on eBay now for as little as 20-30 bucks, so it clearly wouldn’t add too much to the overall price to build a little wireless system into the Spark, maybe even with a charging slot for the transmitter unit.

Finally, Positive Grid can probably improve on production and distribution; there have been reports of Sparks taking a long time to arrive – although when I bought mine it rocked up in three days, and you’ve got to cut companies some slack during the supply chain and manufacturing chaos of the COVID era.


I’ve used the Spark with a couple of different electric guitars, an acoustic-electric, the Fender Acoustasonic Jazzmaster, and an electric bass with active pickups. I’ve used it soft, late at night, without waking the kids up. I’ve used it with headphones, and I’ve cranked that sucker up and rocked the f*$# out. In all cases the Spark has been a joy to play with, especially since I stuck some foam inside to take some of the boom out. If music equipment is to be judged by how much it makes you want to play, then as a novice I’m prepared to call the Spark a home run.

There is nothing else on the market that can do what this humble little machine can do – a fact I find very surprising. There’s a reason this thing has been hyped so hard; it’s a super neat little package offering a nearly endless range of sounds in a way that’s fun and simple, with a ton of depth below the surface for knob-twiddlers. For a beginner like me, it feels like instant rockstar in a can, and I’ve seen plenty of pro players, including pantheon-level gods like Steve Vai, starting to find room for a Spark in their studios.

The fact that this thing sells for a list price of just US$299 (don’t pay that, it’s perpetually on sale and gets down as low as $209) makes it a ridiculously affordable practice amp for a lot of guitarists, a do-it-all machine for others, and one hell of a gift you can put in the hands of a learner. Frankly, I’m blown away.

A nice little retro design that won't offend the eye sitting on a bookshelf or desk
A nice little retro design that won’t offend the eye sitting on a bookshelf or desk

Positive Grid

Any guitar amp company that’s not frantically working on something like this is either mad, or looking backwards – or simply doesn’t have the modeling chops to take it to Positive Grid on this new battlefield. I’m certain we’ll see a larger pro version soon enough, which builds in even more of the BIAS FX capabilities. Heck, the desktop software can actually analyze your guitar setup and tone, and then do a decent job of making a Rickenbacker sound like a Les Paul or a Flying V – as well as running multiple effects chains in parallel.

Positive Grid has plenty of tricks left in its bag for future Spark descendants, and that’s part of the fun of this amazing little amp; as good as it is, this is a first try, and we can clearly see how much better it’s going to get when version 2 drops.

Believe me, you don’t want to hear this amp demonstrated with my shonky playing. Tone, as they say, is mainly in the fingers, and my fingers are fairly vacant at this point. So let’s throw it over here to Tyler from Music is Win for a terrific video demo, in which he takes his top eight iconic guitar tones, from John Mayer’s Slow Dancing in a Burning Room, to Van Halen’s Eruption, Steve Vai’s For the Love of God, Hendrix’s Foxy Lady and Queen’s Bohemian Rhapsody, and recreates them in seconds using downloaded tones for the Spark. Extraordinary stuff.

The 8 Greatest Guitar Tones. EVER.

Source: Positive Grid