Positive Grid branches out from the Spark with the Reactor – an AI-powered combo that can generate tones from images and adapts to your playing
The firm’s first major foray outside of the Spark family could become a fierce new force in the smart amp market
Positive Grid has announced its first new amp range outside of the Spark family, with the Reactor series of intelligent 1x12” combos arriving with some new ambitious technology advances.
Available in 50- and 100-watt packages, the Reactor amps become Positive Grid's closest rivals to the Boss Katana and Blackstar ID:X platforms, though look to get ahead of the competition with some market-first features.
Indeed, the Reactor lineup is offering “a new approach to amplification that builds tone from the ground up”, with its 'Amp Intelligence' – notably not 'Artificial Intelligence' – engine building on the success of the Bias X plugin’s prompt-generated tones.
Dedicated signal chains are said to be generated in seconds, thanks to the all-new companion Reactor app, with entirely custom amps sometimes created in the process – and they all promise to be dynamic under a player’s fingers.
Importantly, though, all tones are fully tweakable, with a fairly comprehensive set of controls on the amp itself. There’s an Amp dial for Clean, Warm, Grit, Crunch, Hi-Gain, and Extreme flavors, alongside Gain and Master controls, a three-band EQ, and six on-board effects including a noise gate, compressor, overdrive, delay, reverb, and modulation.
But there are also “two controls you won’t find on any other amp” via the AI-powered Push/Smooth and Heat mini-switches. The former is a three-way switch, with the middle position the default. In Push mode, it adds more bite to “cut through the mix without touching your gain,” while Smooth makes tones a little warmer.
The Heat control, on the other hand, has five stages for affecting the amp’s response. More heat increases attack and harmonics, while less heat yields a more “elastic, open” tone.
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As for how those tones are generated, the Reactor app offers three distinct modes for sound creation via its Amp Intelligence tech: by text prompt, by image, or by audio snippet. In turn, eight effects be stacked simultaneously, adding wah and EQ to the mix, with the signal chain fully customizable.
By extension, there's also a new Tone Memory feature that analyses and adapts to your unique playing style over time, filtering in automatic tonal refinements to best fit your own sound.
“The more you use it,” Positive Grid says, “the more it sounds like you.”
On the flipside, the back panel is heartily decked out. A USB-C input allows players to plug directly into their DAW, while there's also a 3.5mm headphone out and 1/4” jack line out, which sends its in-built cab sim along the line.
And for good measure, there’s an input for the partnering Reactor footswitch (sold separately), which can also connect wirelessly via Bluetooth and has an expression pedal input and a MIDI input.
In addition, it can serve as a Bluetooth speaker and has built-in Wi-Fi for downloading updates without needing to connect to a computer.



There are unlimited preset slots in the app, too, which makes it a handy storage system for the tones that don’t make the eight onboard slots saved on the amp itself.
It’s packing a lot, then, with the 50W model costing $349, and rising to $449 for twice the power. The footswitch is priced at $149. Those are very competitive prices indeed.
In Guitar World's early review, the ambition of the project was applauded, and despite some AI teething problems, the package was deemed a worthy companion to the Spark and a superb addition to the Positive Grid family.
See Positive Grid for more.
A freelance writer with a penchant for music that gets weird, Phil is a regular contributor to Prog, Guitar World, and Total Guitar magazines and is especially keen on shining a light on unknown artists. Outside of the journalism realm, you can find him writing angular riffs in progressive metal band, Prognosis, in which he slings an 8-string Strandberg Boden Original, churning that low string through a variety of tunings. He's also a published author and is currently penning his debut novel which chucks fantasy, mythology and humanity into a great big melting pot.
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