S M F 30 Watter

Many of you have asked about the S M F amplifier shown in a previous workshop picture of the home page. This is an "S M F 30 Watter" ( yes that is its model name) As its name suggests it is a 30 watt class A amp from the Mark Sampson stable of Matchless & Badcat .   S M F stands for" Sonic Machine Factory" .  Just like Matchless & Badcat amps, it is built like the proverbial brick outhouse, over engineered with the massive transformers and top class components.  I think these were made during a spell of, shall we say between jobs, if you get my gist!

Below are some pictures of the amplifier, the owner is Dan Anderson.
Dan also has a Matchless DC50. He plays in a local band Motel 6.

SMF amp

Front view, the SMF logo has a revolving array of led's
which stop when in standby mode.

SMF amp

Front panel removed

Three images of the unusual rear opening flap, attached at the bottom with a piano hinge, and locking side catch giving the choice of a closed or open back.

Chassis top view, valves mounted inside.

Neat PCB 5 X 12AX7 & 2 X EL34

Note the dark grey cathode bias resistors

The four diodes of the solid state rectifier as fitted to this amplifier

A hole has been pre - cut for an optional valve rectifier

I will load a picture soon of the chassis mounted in its new cab as it is now.

I have no schematics or any service information for this S M F 30 Watter amplifier. One thing I will say is, that is gets very hot! Needs a cooling fan.

This is an unusual cast brass logo I removed from a 1961/2 AC30 many years ago. In all my years in this business, I have never seen another like it. I wonder if Jennings had a run made, and found they were just too expensive. I would be interested to know if you may have one, or seen one like it. This is no home made effort, it is a really professional part.

Have a look at the front and back images.

brass Vox nameplate brass Vox nameplate back


Copyright © John Beer    Jan 2007 All rights reserved


Old time muso,  just loves this line sexy modelling amp!!!