British Bluesmaster

Vintage JTM Tones with London Power Power Scaling


Choose you own cosmetics for free!

British Bluesmaster Head

British Bluesmaster Series 2x12 and 2x12 Cabs
Cabinet Impedance
British Bluesmaster Series 2x12 Cabs
Cabinet Impedance


Early Marshall amps were incredible—-rich, thick, bluesy and mean! There just something about a KT-66 loaded early 60’s JTM. Jimi Hendrix, Eric Clapton, Angus Young, Joe Perry and countless others have used them. However they too loud to be used by most players. They are great pedal amps but the real magic is getting the amp to sweet spot. The British Bluesmaster delivers all those early Marshall sounds but with variable power so you can crank it up! The volume can be controlled as transparently as possible from full power down 1/10W.

The channels are internally jumpered so you don’t need a patch cable. Also we’ve added a bright boost switch to the amp (not pictured) so the amp is more useful darker guitars or if you want little more bite. The SAG (the tube rectifier effect) is completely variable so you can go from solid-state rectifier sounds to tube rectifier sounds and beyond!

London Power’s Power Scaling:

The 60s and 70's Plexi are incredibly  loud amps and were designed for big stages.  They too loud for most players to use even in a club setting.  The British Overdrive series features variable power which solves this issue.  Power Scaling allows the player to dial in anything from full power down to 1/10W.  So these amp are capable of playing anything form a bedroom to a stadium.  Many amps have  "wattage" and "power" controls that sound unnatural. London Power’s Power Scaling  is different from most of these and very transparent.  Plus in any setting below full power it extends the life of the power tubes.   

Other Features:

Linked Input:  

The amp has a linked input so there no need to use a patch cable to jumper channels. This allows you to blend the sounds of normal and bright channels.

SAG Control:

One of the cool things about JTMs was the bloom of notes that comes from the use of tube rectifier. The one trouble is that the sag is set meaning you cannot get more or less and that the sag changes with volume changes. Instead of the tube we’ve added SAG control. It allows the user to adjust the sag/compression and makes the amp more reliable!


Tube Swapping:  

The 20, 45 and 100 Watt versions all come with KT66 power tubes but can use any of the following power tube types with re-baising: EL-34, KT77, 5881, 6L6WGC, 6L6GC, 6V6 or 6550s. Bias ports and externally accessed bias pots allows the user to swap tubes. 



All tube,  Bright and Normal volume controls, boost switch, Crisp/Stock Switch, Vibe Switch (Negative Feedback)  treble, mids, bass, and presence, power and limit controls,  ON/ OFF Switch,  hand wired for great sound and reliability with a method that shortens the signal path, super quiet grounding for low noise, special resistor selection for low noise and great tone, adjustable fixed bias, solid state rectifier.

Malory 150 and Panasonic Tone Caps, Panasonic/Nichicon Ultra Long Life Filter caps, Classic Tone USA output transformer,  Hammond power transformer, Switchcraft or Neutrik jacks, Carling switches, aluminum chassis, 12 ft power cord JJ's Tubes. 

Don’t waste your time or blow out you ear drums—get awesome tone!



Customer Comments:

“After a delightful evening tweaking my Bluesmaster, I can put my perceptions into a review.  You may comment as you see fit.  Here we go.

I received my Carl’s Custom Bluesmaster 20 watt a couple of days ago and find it to be the best amp I have ever come across.  I’ve spent a fortune trying countless tube and solid state amps, all high end, and while they each have their own great sound, none produced what I heard in my head, but I got by with the gain just high enough to “put hair on it,” without sounding like a 14-year-old who doesn’t know how to use his new distortion pedal.  Not to mention the fact that most of my practicing is at home, where I could never really let the amp move the speaker, and the sound was ultimately never satisfying, often frustrating to the point of blunting my interest in playing. 

Not so with the Bluesmaster.  Right out or the box I recognized that basic tone, flowing, creamy and singing, and all your recalled tones from the early 1970’s come rushing back.  The guitar sounds “true” with the Bluesmaster driving humbuckers though the old 212 Celestion cab.  The London power scaling (“Variable Power”) takes a bit of experimenting with (like with that exotic seasoning that was missing from your favorite dish), but after a few hours practice, I use the Limit control as a volume knob (employing the actual wattage knob as a sort of gain governor).  True to Carl’s instructions, keep the “Limit” level lower than the wattage level, and the creamy overdrive stays genuine (as opposed to reminiscent of a gain pedal, never quite there), just as you remember from those priceless LPs.  What you hear out of a Bluesmaster is almost like some  fundamental timbre that separates this from all the modelling amps (and many tube amps) out there, ever closer, but still hopelessly far away from what those of us who know that sound from “back in the day” are seeking.  Open chords sound like a roar, but with a tight, smooth character, no circuit-generated gravelly candy sounds here. 

It’s difficult avoiding the use of wine-tasting jargon, but Carl’s new Bluesmaster amp is enough to satisfy even the most frustrated jaded cork sniffer.  My only concern is that I can’t stop playing it.  If vintage Marshall is what you’re hearing in your head but never through your ears, give a Carl’s Custom Bluesmaster a listen in a real live setting, and you’ll feel right at home. 

Bravo. “

Dennis O.