Gallien-Krueger: The Forefather of Modern Bass Amps

Gallien-Krueger is one of the biggest names in the bass amp world, seen on stages all over the world and used by legends such as Flea and Duff McKagan! So, what is it that sets GK apart from every other bass amp brand? Find out right here!

James Hurman

James Hurman

History of Gallien-Krueger

Let’s go back to 1968. A young Stanford graduate engineer named Bob Gallien has just built his first amplifier in his garage. He takes it to his local music shop and asks if they’ll sell it. The owner reluctantly agrees to take it on consignment. The very next day, one Carlos Santana walks into the shop and buys that original Gallien-Krueger amp, then takes it with him to Woodstock in ‘69. And the rest, as they say, is history…

Bob Gallien has always been an innovator. He saw the flaws in amps of the time, and with his engineering background, was able to find solutions. In ’68 it was pretty uncommon to find an amp rated at more than 50 watts — Fender Twins being approximately 44W and at this point, not many 100W Marshall Super Leads had made their way into the US.

Using pioneering technology for the time, Bob built his amp with far more efficient solid-state components — allowing it to output a monstrous 226W, and making it about as loud as any amp in the world at the time. Solid state technology also doesn’t suffer from power amp distortion, allowing for more headroom and for the preamp to provide all the gain and compression for a more controlled tone. They also featured much more preamp gain than most others at the time. This enabled the singing sustain that Santana was looking for in his sound.

Gallien soon realised that nobody was making dedicated bass amps. The Fender Bassman and the Marshall Super Bass were simply modified versions of guitar amps. So he set out to redesign the amplifier from the ground-up, with bassists in mind. In his own words: “I have never seen the point in doing things the way others have done them.” Each and every stage of Gallien-Krueger’s amps is pioneered to optimise your tone!

Bob Gallien of Gallien-Krueger

Gallien-Krueger: Key Features

Flexible GK Preamp

Throughout most of Gallien-Krueger’s history, they have made amps with both solid-state preamps and all-valve preamps to cater for different tastes. But there are parts of both of these circuits that are totally unique to Gallien-Krueger.

Most amps have passive EQ controls. This means that it is only subtractive — i.e. the amp is “open” with all EQ controls on 10, and you can only cut certain frequencies. Gallien-Krueger amps use active ‘Serial Variable Q equalisation’. This is a completely revolutionary EQ circuit that allows far more precise control and is voiced specifically for bass. Instead of the typical 3-band EQ, GK uses a 4-band EQ featuring Bass, Low-Mids, High-Mids, and Treble. Not only do you get more precise control, but you can also cut or boost frequencies — unlike a passive EQ. With this serial EQ design, you also eliminate potential frequency cancellation and frequency masking issues that can occur with standard EQ controls. Read more about EQ here.

Although Gallien-Krueger amps are often known for their iconic distorted “growl”, they are also designed to achieve the perfect clean tone. Each GK amp has a gain “trim” control that finetunes the input gain of your signal, so whether you’re playing a vintage output P-Bass or a modern bass with active humbuckers, you can pad the gain to the exact point where it won’t clip or distort. You can then have more control over your gain with the overdrive channel for a natural and controlled breakup.

All of these are features included in both solid-state and valve preamps. So depending on which flavour you prefer, you know you’re not missing out. For valve aficionados, you’ll also be pleased to hear that Bob is very fastidious about his valve preamps. Many high gain valve amps include a degree of solid-state clipping circuitry to increase preamp gain. But if you’re buying any amp from the Fusion Series, you can rest assured that the preamp is nothing but valve. No fancy trickery. No smoke and mirrors. Just pure tube saturation!

Gallien-Krueger Fusion Series Bass Amp Heads

Class D Power Amp

When Bob Gallien started designing and building amps, solid-state technology was still in its infancy. He was an early adopter of this, and was able to pioneer the legendary “GK Growl”. Bob Gallien describes this sound as the result of the power amp “hitting the rails”. A solid state power amp compresses and distorts differently to valve power amp. The GK growl is known for having boomy distortion on the low notes while maintaining clean articulation on high notes.

The hi-fi class D power stage amplifies the preamp extremely efficiently, allowing the preamp to shine. The huge headroom afforded by class D also creates a really “punchy” sound with intense transients that have that same visceral feeling as a kick drum.

Proprietary Speakers

All GK speakers are made in-house in the USA. No other amp brand of their size makes their own speakers. This gives them an advantage as they are able to voice the speakers precisely to their amps.

Most speakers use “round wound” voice coils, while GK speakers use “edge wound ribbon” voice coils. This allows for more winds around the speaker resulting in more efficiency, more volume and a fuller frequency with deeper lows and more present highs. This process is more expensive and labour intensive, but Bob Gallien understands that speakers can truly make or break an amp!

The speakers are also super-light neodymium magnets, that are a fraction of the weight of a ceramic speaker, allowing the amps to be far more portable – perfect for gigging!

Everything down to cabinet bracing is clinically calculated to resonate in phase with the speaker for increased projection and bass. Regular cabs can suffer from phase cancellation which makes the sound thin and nasal.

Unparalleled Quality

Everything from populating circuit boards, to shielding cables, to coiling speakers is done in-house in Gallien-Krueger’s USA factory. This makes GK’s amplifiers some of the highest quality money can buy! They are specifically designed to withstand the rigours of life on the road. And the long list of Gallien-Krueger players can attest to this…

Gallien-Krueger Artists

Flea (Red Hot Chili Peppers)

Flea Gallien-Krueger User

Perhaps the most famous GK player, Red Hot Chili Peppers’ Flea has used these amps for decades to get his signature tone — from punky driving basslines to funky slapping and popping, and clean chordal melodic lines. This is where the “GK growl” is so effective. For those heavy low notes he can get that overdriven grind, while his intricate riffing is perfectly articulate on higher notes.

Duff McKagan (Guns N’ Roses)

Duff McKagan Gallien-Krueger User

For many, 1987’s Appetite for Destruction is hailed as one of the best sounding rock albums of all-time. And laying the foundation for Slash and Izzy, was Duff McKagan with a Gallien-Krueger.

Dave Holland (Jazz Legend)

Dave Holland Gallien-Krueger User

Proving that GK amps can run the gamut of genres, multi-Grammy award winning musician Dave Holland plays upright bass through his GK.

Justin Chancellor (Tool)

Justin Chancellor is known to have great tone, and a great variety of different sounds and effects. And at the foundation of that is his GK amp. His aggressive, heavy riffing is complemented by that “GK growl”, whilst also having the headroom to make it an excellent platform for 46 & 2 other effects!

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James Hurman
James Hurman
James is a member of the Guitar Marketing team and has a particular penchant for vintage gear. He loves Strats, Les Pauls, Fuzz and British amps. He also has an embarrassingly large collection of overdrive pedals on his pedalboard

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