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Gallien-Krueger Fusion 800S 800-watt Ultra Light Bass Head

800W Ultra-light Bass Head with Class D Power Amp and Tube Preamp, 4-Band Active EQ, and Switchable Tube Overdrive
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Gallien-Krueger Fusion 800S 800-watt Ultra Light Bass Head
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Ultra-light, Tube-powered Bass Amp Head with Monster Tone

The Gallien-Kreuger Fusion 800S is an 800-watt compact, ultra-light bass amp head with a Class D power amp and an all-tube preamp with tube-powered overdrive. Vintage-voiced with modern punch and clarity, the Fusion 800S, can roll with any genre, churning out crisp and articulate clean tones, big-bottom low end, and gritty distortion that'll knock the house down. With its small form factor, ultra-light construction, and robust interconnection system, it's built for the touring bassist. Additionally, a fully stacked feature set, including illuminated knobs, effects loop, and balanced DI, makes the Fusion 800S one of the most versatile heads of its size bassists at Sweetwater have ever seen.

Vintage-voice with a modern punch

The Fusion S Series pairs GK's signature punchy power section with a characterful tube preamp for a warm, vintage-style sound with modern punch and heft. The preamp is packed with three 12AX7s, with one dedicated to the overdrive channel, for the kind of growling distortion you can only get from overloading a tube. Sculpt your tone to fit any genre with GK's classic 4-band active EQ and push-button voicing filters, including "Bump," "Contour," and "Presence," for on-the-fly adjustments. On stage or in the studio, the Fusion 800S is a tonal chameleon perfect for any performance style.

Built to take a beating

Chucked in vans, tossed in trunks, and dragged from show to show, bass amp heads take a lot of abuse, and, over time, the electronics can start to suffer. This means your tone starts to suffer, too, and that is simply not acceptable! The Fusion 800S is fortified to handle even the heaviest use. Boasting the same robust interconnection system found in GK's Legacy Series bass amp heads, Fusion S Series heads employ gold connectors on their circuit boards, which deliver a more reliable and purer tone than the standard tin connectors found in other heads.

Jammed with features bassists love

GK loaded up the Fusion 800S with a host of features designed with working bassists in mind. Illuminated knobs to adjust your tone on dimly lit stages without squinting into the dark. Mono 1/4-inch Send/Return for patching in your favorite external effects units. Impedance selector to ensure your 2, 2.7, 4, or 8ohm cabinet receives the optimal load. Balanced DI output with pre- and post EQ for patching into a live-sound board or recording console. And it's all housed in a rugged metal enclosure to withstand those aforementioned vans and trunks!

Gallien-Krueger Fusion 800S 800-watt Ultra-light Bass Head Features:

  • 800-watt compact, ultra-light bass amp head
  • Class D power amp
  • Analog tube preamp
  • GK's classic 4-band active EQ
  • Foot-switchable tube overdrive
  • Bump, contour, and presence voicing
  • Balanced XLR output with pre and post EQ
  • Unbalanced 1/4-inch FX loop send and return
  • Illuminated control knobs
  • Aux input and headphones output
  • 2, 2.7, 4 and 8ohm load capacity
  • 11.5-inch width x 11-inch depth x 2-3/8-inch height

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Tech Specs

  • Type: Solid State
  • Number of Channels: Single Channel
  • Total Power: 800W @ 4 ohms, 400W @ 8 ohms
  • EQ: 4-band Active EQ
  • Preamp Tubes: 3 x 12AX7
  • Inputs: 1 x 1/4", 1 x 1/8"
  • Outputs: 2 x SpeakON (balanced), 1 x XLR (direct out)
  • Headphones: 1 x 1/8"
  • Effects Loop: Yes
  • Footswitch I/O: 1 x 1/4" (overdrive, tone control)
  • Footswitch Included: Yes, 1-button
  • Cooling System: 2 x Internal Fans, Side Air Vent
  • Power Source: Standard IEC AC cable
  • Height: 2.37"
  • Width: 11.5"
  • Depth: 11"
  • Weight: 5.5 lbs.
  • Manufacturer Part Number: 302-1210-A

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Customer Reviews

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Rated 5/5

GK Fusion 800S

Been a GK user forever and this amp did not disappoint me a bit. If you want a big fat bottom end, you will get it with this amp. All the features you could want and very easy to dial it in. Tons of punch too. This amp can get loud so be careful. :-)
Music background: Semi retired pro
Rated 5/5

GK Has Blown It Out of the Water!

I've always been a GK fanboy and this is my first tube head. I went with this model after watching many a review video on it. They don't do this amp justice. The 800 Fusion is more than most will need, and if you need more there is the 1200 to go with. The warmth this little bad boy brings is uncanny and the OD tube drive is the best I've heard in a long time.

I've coupled this amp with some DG pedals, but it could stand on its own in bass tone. If you want to be something other than an Ampeg flunkie, you can't go wrong with these new GK amps. Buy it, play it, convert to the cult of GK.

Hype aside, all the tone options on this amp are what makes it sing. The EQ curve options are choice and the ability to use cabs that go down to 2 ohm, 2.7 ohm, and classic 4 ohm stable is amazing. I've coupled this amp with a Fender 410 Rumble and Fender 115 Bassman Neo. I also switch out with a GK Neo 212 II cab that just pounds it with this amp. No issues so far and I get a little braver on volume every time I jam out with it. It continues to deliver and make my cabs obey.

High praise indeed.
Rated 5/5

Growl........

At first, the amp was a little tricky to dial in. I'm somewhat new to GK amps. I couldn't get any drive out of the overdrive. The "Trim" is basically an overall gain. The "Normal" control is a volume for the clean channel. The overdrive channel becomes it's own pre-amp volume. And the "Master" is a speaker volume. Makes sense? In other words, always have the Trim real high.

FYI: You need a 2-conductor Speakon cable. My expensive Mogami cable wouldn't fit. Buy a ProCo speakon cable. For what this amp head costs, it should come with a matching speaker cable. And the speaker outputs are not combo jacks so you can't plug in a 1/4 speaker cable.

Because you can push the buttons in for secondary function, they feel a little loose. I also wish they wouldn't of crammed all the knobs onto 1 row. Maybe they could of put the overdrive on top and the rest of the knobs below. Tone-wise, you can get all kinds of sounds. You can spend a lot time playing with the secondary functions. You can get a super-clean tone or a raw tube-crunch. I would say it's an all-around amp head that can cover any genre of music.

The overdrive channel lets you kill the highs or add more drive to the lows. If you're looking for a heavy Darkglass overdrive, then this is not the amp for you. It's more like an organic, SVT tube-tone that you can dial in halfway and just leave on all the time. Darkglass is 100% solid-state tone. Remember that when you're shopping for an amp head.

Because I live in an apartment, I can't mike-up a bass amp for recording. So when I was recording direct, with my SWR gear, I always had to use software to add dirt or saturation to my bass tracks because going direct sounded too clean. Adding dirt makes the bass stick out in the mix. With this GK amp head, I can add a touch of the tube overdrive and it gives a subtle SVT crunch.

Going thru the speaker, I can only jam on it at very low volume. Looking forward to getting out of my place, away from my neighbors, and pushing this amp head to the limit.
Music background: Always learning.
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