Gallien-Krueger 400RB-II Vintage Rackmount Bass Head Early 1990s 200W Black - Iconic GK Growl

Gallien-Krueger 400RB-II Rackmount Bass Head – Early 1990s, Black, 200W RMS / 400W Peak, Vintage Solid-State Icon w/ Legendary Preamp.

Classic early '90s GK 400RB-II – the compact sibling to the revered 800RB, sharing the same killer preamp circuit that defined modern bass tone. This Series II version offers effortless boost (no footswitch needed, though compatible), detachable IEC cord, and switchable voicing filters (Lo Cut, Mid Cut, Hi Boost) for versatile sculpting.

Compared to the 800RB:
This version is preferred to the 800RB by those who wish to overdrive the preamp and still be reasonably loud. It is a flavour of it's own, not a flat out distortion.
Secondly, very few actually use the bi-amping functionality of the 800RB. If used with only one 4ohm cab, the 800RB is 300W RMS amp - the difference is not that big.
And finally, this is a fairly light and compact amp at 6,7kg and 2U height. Don't ask me for Rack ears though - these are nearly impossible to get. I heard that if you write to GK support, they might be able to send you rack ears from the IV version, which match this one as well.

Signature GK sound:

• Punchy, articulate 'growl' with tight lows and crisp highs that cut through any mix
• Smooth, dynamic solid-state tone with real character – not sterile like many vintage SS amps
• Great for low-volume grit/distortion from the preamp (ideal for rehearsals/small gigs without cranking)
• Used by legends: Flea (Red Hot Chili Peppers), Mike Dirnt (Green Day), Krist Novoselic (Nirvana), Joe Lally (Fugazi), and more

Specs & Features:

• 200W RMS / 400W peak into 4 ohms (hefty punch for its era)
• 2U rack size, lightweight, side handle + rack ear screws (no ears included)
• Foot-switchable boost with dedicated control. Always on if no fsw present.
• Effects loop, two speaker outs (min 4 ohms total – run two 8-ohm cabs)
• Line out (not XLR, TS unbalanced only)
• Passive heatsink cooling (no fan noise)
• Made in USA | Early 1990s production

Condition: Fully functional – all pots/jacks/buttons smooth (no scratchiness), except for the input gain potentiometer, which works fine for 95% of it's travel, and in the last approximately 2 mm of travel, there is a volume increase. This could only be a problem for players who require input gain to be set at max. For 99% of players this is a non-issue, but has to be mentioned.

Cosmetically 'well-loved' with visible wear, scuffs, and dings from decades of use (see detailed photos). Some potentiometer knobs are dinked, but are not falling off. Minor loose fuse socket (stays in place, no operational issue). Imported from USA last year as backup; tested and reliable.

Important EU note: Operates on 110V – use a quality step-up transformer like Tube Amp Doctor (~€100 shipped) for safe 220–240V operation.
Avoid internal transformer conversion to preserve original tone.

Categories: Bass Heads > Rackmount / Vintage / Gallien-Krueger

Ships securely & tracked from Prague, Czechia. Open to offers – happy to send more photos, or answer questions!
Perfect project piece or tone chaser rig addition.