Shaftesbury amp, no model name, serial no 94251

Latest filter cap date: November 1961 

Controls:

Tremolo - Depth /Speed, jack socket for footswitch (original lost)

small bulb flashes on when overdriven (labelled "Max. Power")

Filter - 3 position tone selector 1 = full range, 2 and 3 are progressively tinnier, cutting the bass

Bass and Treble for both channels

Inputs section of panel marked 'Mixer' 

Four inputs, 2 channels - 2nd channel with tremolo

Valves:

3 x EF86 and 1 x ECC83 in Pre-Amp.

Power amp - 2 x EL34, 1x ECC83, GZ34 rectifier

Size:

19" High x 24" Wide x 10" Deep

Modifications:

Mains transformer replaced (+ 3 core power cable added)

Original EMI elliptical speakers removed.

Extra hole drilled in chassis, OT rewired - for 2 x 15 ohm outputs (to separate 'Dallas' 12" cabs)

Original set up may have been 2 x 8 ohm speakers in series, with single 15 ohm extension speaker output on separate tap from OT, or perhaps 2 x 15 ohm speakers, one with in-line extension speaker option (that seems less likely to me, don't know what other amps were doing at the time). 

Unclear what original OT wiring was doing, but leaving as it is for now. 

After replacing the ellipticals (2 x 15 ohm speakers, one on each tap) and promptly blowing one, I will soon be going with 2 x 8" Celestion 50W 8 ohm speakers in series on the 'internal' 15 ohm tap, leaving the separate 15 ohm extension for special occasions/more volume.