Gallien-Krueger Fusion 800S review

A bass amp head for pros who want a lightweight high-powered head offering the best of both worlds between solid-state and tube

  • £1099
  • $1249
Gallien-Krueger Fusion 800S
(Image: © Gallien-Krueger)

MusicRadar Verdict

A high-end hybrid with range and power, the Fusion 800s is a stylish, intuitively designed platform for all manner of adventures in low-end.

Pros

  • +

    Powerful, comprehensive EQ.

  • +

    Lightweight and classy design.

  • +

    Illuminated knobs.

  • +

    Footswitchable drive.

  • +

    Effects loop.

Cons

  • -

    Priced for the serious player but value all things considered.

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Gallien-Krueger Fusion 800S: What is it?

The Gallien-Krueger Fusion S lineup arrives with the tagline “punchy warmth” and that cuts to the chase when it comes to the core bass guitar tones offered by these high-end hybrid bass amp heads.

The hybrid design finds a Class D power section complemented by a valve-driven preamp, with presses a trio of 12AX7 into action to add the aforementioned punch and warmth, with one solely dedicated to the noble business of overdrive provision. 

This build is eminently practical, keeping the amplifier lightweight – this weighs a hair over 2kg – and retaining the tone mojo for which we still, over a century on, laud the vacuum tube for. And G-K, being G-K, they’ve also outfitted the series with an active four-band EQ and packed this with clever features without ever feeling as though they were at risk of over-designing the amplifier.

The front panel is tidy, clean, easy to navigate, and the anodized aluminium chassis looks damn cool in low light whereas the cool blue LEDs illuminate the dual action knobs that operate as rotary dials with secondary push functions. 

There are 10 in all. Trim/Voice adjusts the level from the input, with an LED indicator to flash red should the incoming signal from your bass be too high for the circuit.

Its secondary function, Voice, toggles the additional EQ pre-shape, with the knob illuminated blue when the Voice mode is active. Normal/On controls the volume for the Normal channel, with pushing it in activates the channel. 

Likewise, Overdrive/On. Push it in, engage overdrive, and turn clockwise for more overdrive, and you will also see that the Edge/Cut and Level/Body controls will light up, too. 

Gallien-Krueger Fusion 800S and NEO-IV 410 cab

(Image credit: Gallien-Krueger)

Its secondary function, Voice, toggles the additional EQ pre-shape, with the knob illuminated blue when the Voice mode is active. Normal/On controls the volume for the Normal channel, with pushing it in activates the channel. Likewise, Overdrive/On. Push it in, engage overdrive, and turn clockwise for more overdrive, and you will also see that the Edge/Cut and Level/Body controls will light up, too. 

These controls are all related, with the Edge/Cut adjusting the high-frequency response of the drive while pushing it in engages or bypasses the Cut feature that reduces frequencies above 5kHz. You’ll see this turn from white to blue when you engage the cut feature. When overdrive is on, the rotary control on the Level/Body dial adjusts the output of the drive, while Body is an on/off boost in the low-end for extra woomph. Again, it glows from white to blue when active.

Bass/Bump boosts or cuts bass frequencies with its secondary push-activated feature opening up a can of whoop ass with even more low-end enhancement. Lo-Mid/Cont does likewise with low-mid frequencies with the push feature activating a contour that scoops your sound, boosting lows and highs.

Gallien-Krueger Fusion 800S

(Image credit: Gallien-Krueger)

Hi-Mid/Hicut, again, boosts or cuts the hi-mid frequencies with Hicut allowing you to nix annoying string squeak and assorted high-end frequencies that can occasionally ruin a take. Treble/Presence and Master/Mute are self-explanatory and round out the controls on the front.

Around the back you’ll find a direct XLR out with ground lift and pre and post-EQ, headphones out, aux in, an effects loop, tuner input, and a footswitch input for turning the overdrive circuit on and off. Finally, you’ve got your load impedance switches and a pair of parallel twist-lock speaker outs.

We paired this with Gallien-Krueger’s NEO IV 410 cabinet, which as the name suggests is loaded with a quartet of 10” neodymium drivers, a Paragon horn and a 1” tweeter. And might we say those neodymium drivers are an inspired choice, with the cabinet weighing in at a relatively manageable 28.6kg.

Gallien-Krueger Fusion 800S and NEO-IV 410 cab

(Image credit: Gallien-Krueger)

Gallien-Krueger Fusion 800S: Performance and verdict

The Fusion 800s is cooled by a pair of fans that are only activated when the unit reaches a certain temperature, and speed up as the amp heats up. It’s an efficient way for the amp to cool itself and it means that, quite often, the fans won’t come on. It would be useful to have a switch to turn the fans off when recording, but that’s probably not going to be an issue. This amp runs quietly.

Also consider...

Best bass amps: Darkglass Microtubes 900 v2

(Image credit: Darkglass)

Darkglass Microtubes v2 and Alpha Omega 900
At this price point, the Microtubes v2 and Alpha Omega 900 are not casual purchases, but the superior tonal options on offer are enough on their own to make these very competitive at the upper end of the market. Couple those killer tones with an enviable set of features catering for every conceivable need, and you have some seriously envy-inducing product.

Ashdown RM-800-EVO 11
A flyweight amp head with a lot of muscle under the hood, the RM-800-EVO II taps Ashdown’s design nous for a fully-featured setup that caters to all styles, not to mention all musical situations, too.

Its voice will soon disturb the piece. This 800-watt model has a lot of power behind it. There is a 450 and 1200 in the series too if that’s more suitable for your needs. What’s eminently obvious from a cursory run-through of its sounds is that this hybrid build, and the control G-K has given you over your sound, is all designed to appeal to the broadest demographic of bass players possible.

Yes, maybe a bit too pricey for the beginner but this has all different kinds of tones for the serious amateur and the pro to get down with. Are you the sort of player whose progressive slap and pop require a certain effervescence from your amp? Well, just hit that contour button, adjust the EQ to taste, and it will respond in kind.

Looking for plummy thump? Well, the Bump function has you covered, which, depending on where you set the overdrive, can either be plummy and round and jazz-friendly or a severe test of the floor’s structural integrity.

Looking for gritty rock? That overdrive, footswitchable too, can bring out your wild side, offering drive that sounds of a piece with the amp itself, an extension of its gain stage as opposed to an outboard overdrive pedal

The Fusion 800s presents players will credible options via a fully-stocked control panel that’s easy to navigate, and courtesy of that Trim dial, you can adjust the input gain to make it pair well with all kinds of basses, making for a more exacting experience than using Hi/Lo inputs or a pad switch. 

It’ll blink red to alert you to the signal clipping, but once you’ve set this up, the full bounty of the amp’s tones await. It is a tonal chameleon in many respects, offering quick and easy EQing solutions to transform your sound, with usable, inspiring sounds wherever you turn the dial.

MusicRadar verdict: A high-end hybrid with range and power, the Fusion 800s is a stylish, intuitively designed platform for all manner of adventures in low-end.

Gallien-Krueger Fusion 800S: The web says

"The head and cab may be lightweight, but the sound is not: this rig delivers the huge, clear tone for which G-K is known. Engaging the Bump filter adds gut-rumbling lows: An extra-girthy sound that will fill out even the deadest of rooms. 

"Although the G-K sound is easily had, the Fusion 800S has so much more to offer. Whatever my basses wanted to do, this rig was there for it."
Bass Player Magazine

Gallien-Krueger Fusion 800S: Hands-on demos

Gallien-Krueger

Gallien-Krueger Fusion 800S: Specifications

  • MADE IN: USA
  • TYPE: Hybrid bass amp head with valve-driven preamp and Class D solid-state power amp
  • POWER: 800 watts
  • FEATURES: Tube preamp with three 12AX7s, four-band EQ, footswitchable tube overdrive with tone control (footswitch included), Voicing filters (Voice, Bump, Contour, Presence), balanced XLR output with Pre and Post EQ, unbalanced 1/4” send and return, Aux input, headphones output, twist-lock speaker outputs, switchable impedance (2, 2.7, 4, 8 ohms)
  • WEIGHT: 5.5 lbs 
  • CONTACT: Gallien-Krueger
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