The Mistress range

When Tim Branston's classic V-fronted amp came in for repair in autumn 2013, it needed only a few minor repairs - mainly replacing old Hunts capacitors with modern equivalents - before it sounded immense. Its classic design has 3x ECC83 pre-amp valves, and 2x EL84 12W output valves. An EZ81 valve rectifier gives it the classic valve "sag" we expect from early 60s and 70s British blues recordings.

Inspired by this experience, I created the Branston Mistress. Its production chassis has improved weight distribution, and is formed from laser cut aluminium. The cabinets are CNC cut from Forestry Standards Comission 9mm Baltic birch ply, then hand assembled. The cabinets are then hand profiled and finished, before they are introduced to their speakers and chassis.

Several variations are available, including a switchable gain front end, TMB tone control, a choice of phase splitters, high powered or single-ended (even harmonic rich) 6L6GC power stages, and dual rectifier, pentode / triode modes.

Cabinets can be built from CNC precision cut birch ply, or if you're after something special, we can offer finished hardwood cabinets. We even offer the more traditional vinyl coverings, if you're into that kind of thing, but you can go wild on your colour scheme, as we can pretty much get any shade or pattern you desire.

Click on the images below for photo galleries

Donna-Lee

Serial number 0003 (master build)

Shaking some of the tradition, this one has been built using more modern design principles. It has only 2 ground points - one for the pre-amp & oscillator & 1 for the output valves. This means it has really low noise levels, and is more suitable to a studio situation. The inputs are back to how the original amp was laid out and it's easier to jack from the swell channel to the normal channel to give more tone options.

Donna-Lee fascia, side on
Features:
2 input Normal channel
2 input Swell channel (tremolo)
Single tone control on each channel
Footswitch for Swell oscillator defeat
1970s vintage Elac 10N/94 10" Alnico drivers.
VVT custom magnetics
JJ (Slovakia) ECC83MG / EL84 valve set
Shielded thermoset valve bases
CDE signal line polypropylene "orange drop" capacitor set
1KV Ceramic oscillator cap set
Song Huei volume and tone pots
Varnished fabric covering
Point-to-point construction
Shielded signal wiring
Low noise single ground point pre-amp wiring
Chicked head and precision knobs
Rugged & rattle-free carry handle

Future builds of this amp will be based on this build. Specification of parts may vary. 


This now has the Elac 10N/94 10" speakers fitted, and now has the crisp tone and clarity that this design deserves.

Cherylyn

Serial number 0002 (sold Nov 2015)

Cherylyn was built with transparency in mind - covered in sheer fabric so you can see the construction, and the speaker baffles are not painted so you can see where the speakers are. Construction lines and cuts are visible, as are the laminations of the plywood. The tremolo speed, valve clips and closed construction are similar to the original spec.

Cherylyn
Features:
2 input Normal channel
1 input Swell channel (tremolo)
Single tone control on each channel
Footswitch for Swell oscillator defeat
Celestion 7442 NIB cone 10" drivers
BLS magnetics
Tung-Sol (Russia) 12AX7 / EL84 valve set
Ceramic valve bases with spring clips
Poly and ceramic capacitor set
Song Huei volume and tone pots
Sheer fabric transparent varnished covering
Tag board construction
Shielded signal wiring
Chicked head and precision Eagle knobs
Rugged & rattle-free carry handle

This amp has a clarity of tone that just has to be heard, mainly due to its Celestion 7442 NIB coned speakers and closed construction. If you're into funk, give this baby a listen.

This amp was sold in November 2015 to the person it was originally designed for. Photos of her in her new home can be found on the Facebook page.

Betty Sue

Serial number 0001 (sold Feb 2015)

Betty was built as a production version of Rosie. The main improvements on the prototype are the CNC cut cabinet, laser-cut slimmer chassis, using 2mm aluminium, laser-etched fascia, and much tidier wiring. It has the same Elac 10N/94 vintage speakers, same valves, resistors and capacitors. The fabric on the outside was also cut differently to prevent premature fraying and peeling.

Betty fascia
Features:
2 input Normal channel
1 input Swell channel (slow tremolo)
Single tone control on each channel
Footswitch for Swell oscillator defeat
Elac 10N/94 10" drivers
BLS magnetics
Tung-Sol (Russia) 12AX7 / EL84 valve set
Shielded thermoset valve bases
Poly capacitor set
Citec UK volume and tone pots
Varnished fabric covering
Tag strip construction
Shielded signal wiring
Mesh breather allows viewing of valves
Chicked head and precision knobs
Rugged & rattle-free carry handle

This is a full sounding amp, with a crispness and clarity to its tone. I'd say this is one for the British blues revivalists.

"I LOVED it!" Gwyn Ashton - http://www.gwynashton.com/

This amp was sold in Feb 2015 to the person it was designed for, and can be seen around Moseley, Birnmingham, and its surrounding area.


Rosie the Rebel (Custom)

Serial number 0000

Rosie was the prototype. She has a hand cut and crafted cabinet, and the fabric on the outside was stretched between lengths of lath to make sure minimal bubbling occurred.

In 2015 she was rebuilt to a custom spec - my spec; she is mine, after all. She's now a lot more rugged, the graphics look great, and there's a ton of switchable grunt into a gravity defying pair of Celestion T1927 speakers. One like this can be built with Celestion Greenback speakers, or with the highered powered 25W EL84 or 6L6 spec (with double the transformer weight).

Dirty Rosie
Features:
Single input
Switchable channels:
  Clean channel
  Dirty channel
Switch or footswitch operation
Reversed layout - controlled from the front
Celestion T1927 10" drivers with Pulsonic cones
Dual Rectifier - EZ81 / silicon
Shared cathode follower driven TMB tone control
BLS magnetics with over-voltage HT
ECC83 / Tung Sol EL84 valve set
Ceramic valve bases
PP and PE capacitor set
TE Citec pots
Varnished fabric covering
Tag strip construction
Shielded signal wiring
Mesh breather allows viewing of valves
Chicked head and precision knobs
Rugged & rattle-free carry handle

This version of the Mistress amp can also be ordered.

 

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