Gallien-Krueger Fusion 550 Hybrid Valve Bass Amplifier
item# 482104004000000



The Gallien-Krueger Fusion 550 is GK's first bass amp head featuring an all-tube preamp. The Fusion 550 bass head incorporates a uniquely designed 6-stage tube preamp paired with a 500W version of the high-current solid-state power amp used in the GK 1001RB-II. The rich warmth of tubes, combined with the quick, punchy power that G-K bass amps are known for, is an aural experience you must hear to believe.

As if that wasn't enough, GK has inventively incorporated motorized knobs into the Fusion 550 head that allow you to store two different settings. This gives you the ability to dial in a separate overdrive or slap tone and footswitch between them--a first for a fully analog bass amplifier.

The Fusion 550 amp also features a simplified version of GK's exclusive 50-W Horn Bi-Amp System. Dial in the horn where you like it, and as you adjust your volume with the master control, the ratio between the woofer and tweeter is preserved. Other features include a tube driven 4-band active EQ and voicing filters with a frequency select for the contour control. The rear panel features include Neutrik Speakon and 1/4" speaker output jacks, effects loop, tuner out, and a footswitch input jack. It also has a DI output which uses an isolated transformer for ultra-quiet operation.Power Amp
500-watt Class G high-current solidstate power amp
50-watt Horn Bi-Amp System
Toroidal transformer

Pre Amp
Six-stage all tube preamp (three 12AX7's)
Motorized pots allow 2 presets
Footswitchable two-channel motorized gain, master, and horn level controls
Tube driven four-band active EQ
Contour control with 500Hz-800Hz mid-frequency select
Deep and bright switch
Mute switch
1/4" input jack with active/passive switch (-14dB)

Rear Panel
Effects loop & tuner output
Active DI with level control, pre/post, and ground switch
Two Horn Bi-Amp compatible Speakon outputs
Two 1/4" speaker outputs (fullrange only)
Rear-vented temperature controlled fan
**..Mint Condition..** This instrument or product has been played/used and is in virtually new condition; however its packaging may not meet the standards set by the factory. Also, it no longer carries the manufacturer's warranty. If you're looking for a virtually new instrument in possibly less-than-perfect packaging, this is a great value. We feel so strongly that you'll like what you see, we're including our 30-Day Satisfaction Guarantee to this used product, making it a no-risk purchase.

Orders are generally shipped the following business day after payment is received. For example, if your order is placed AND paid for at 1 p.m. Eastern Time on Friday, Music123 will ship it on Monday. We are only shipping eBay orders via standard ground shipping at this time (3-7 business days for delivery once the item leaves our warehouse)**
International Buyers – Please Note: Import duties, taxes, and charges are not included in the item price or shipping cost. These charges are the buyer's responsibility. Please check with your country's customs office to determine what these additional costs will be prior to bidding or buying.


Music123 only accepts payments for eBay orders through Paypal.


Music123 charges sales tax to orders shipped to the following states: Indiana, Missouri, Utah, and California.


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  • Returns

    45 Day Satisfaction Guarantee

    Our goal is your total satisfaction.

    New Gear: If you’re not satisfied, neither are we. If for any reason you’re not completely satisfied with your purchase of a new item, simply return it in its original condition within 45 days of purchase (see exceptions below) and we’ll give you a full refund. It’s that simple. Returned items must be in original, brand-new condition, showing no signs of wear or use such as belt-buckle or pick scratches, scuffs, dings or scrapes on the instrument or collateral materials. Items must also include all original packaging, manuals, warrantees and accessories or your return may be subject to a return handling charge. Please contact us for detailed return handling charges. Your refund will be promptly processed upon successful evaluation of your returned item from our trained category professionals. Refunds are made for product value only, excluding shipping and handling charges. If you received Free Shipping on your order, the value of the uncharged shipping cost will be deducted from your refund.

    Used Gear: If for any reason you’re not completely satisfied with your purchase of a used item, simply return it in its original condition within 30 days of shipment and we’ll give you a full refund. Items not returned in original condition are subject to a return handling charge. Select used item are not returnable.

    International Shipments: Our return policies for new and used gear also apply to international shipments. Please see any additional policies and information shipped with your package for more details.

    Exceptions: There are no returns on clearance, discontinued, vintage, demo and select used items. Additionally, the following items are returnable only if defective OR unopened - strings, reeds, computers, tubes, earbuds, earplugs, recorders, tin whistles, flutophones, "world" wind instruments, harmonicas, raw-frame speakers, drumheads, drumsticks, turntable cartridges, fog fluid, clothing/footwear, body jewelry, sheet music, cleaners, polishes and polishing cloths. Software/soundware, books, CDs, DVDs, and videos may be returned for credit only if they are in their original, sealed packaging. If defective, these items will only be exchanged for the same product. All returned woodwind and brass instruments incur a $10.00 sanitization fee. Returned bows are assessed a $4.00 restocking fee. Returned mouthpieces priced over $300 incur an $8.00 sanitization fee; the fee for mouthpieces under $300 is $4.00. Due to its return policies, you must contact Apple directly to repair, replace or return Apple products. Apple products may not be returned to us under any circumstance. Stringed instruments priced at $1999.00 or more, must be returned within 10 days of shipment.

    Requesting a Return: Contact our experts via eBay messages. Additional information on returns can be found on the paperwork shipped with your package.

    Send your returns to:

    Music123
    (Your RA #)
    4005 N Norfleet
    Kansas City, MO 64161-9231