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Sound Sales Special Six

Acquired November 2009, this wireless set dates from the late 1940s or early 1950s.  A schools receiver built on the same chassis as the Sound Sales DX Plus One. Unlike the DX Plus One it is a complete receiver with C-L-C filtered power supply and KT61 push-pull output.  The output from this set will be of the order of 10 watts; more than enough to fill a classroom or even a school hall.  Bands covered are LW and MW broadcast bands only, no short wave band as with the DX Plus One.
From Sound Sales
From Sound Sales
  Valves are GZ34, 2 x KT61, 6Q7GT, 6K8GT and 6K7GT.
From Sound Sales
  Look at the size of that output transformer! Notice that the output transformer and mains transformer laminations are at 90 degrees - that's how they should be to prevent mains hum.
From Sound Sales
  The underside also reveals Sound Sales heritage as a transformer manufacturer. The large smoothing choke is obvious here, but there's yet another of their transformers at the far right.  This smaller screened transformer is the phase-splitter for the pair of KT61 output valves.    

Sound Sales produced a radiogram with the same, or similar chassis, reviewed in June 1954 in The Gramophone.

Sound Sales DX Plus Four Radiogram. (Price £47 10s. plus £16 11s. 5d. inc. P.T.)
Circuit : 6-valve comprising frequency changer, IF., detector plus L.F., push-pull tetrode output, rectifier. Negative feedback. Output 8 watts. Valves : 6K7, 6K8, 6Q7GT, 2 x KT61, 5Z4.
Radio : Medium Wave-200 to 550 metres. Long Wave-800 to 2,000 metres. Variable selectivity.
Motor : Collaro Type AC3/544 with Studio " P " pickup.
Controls : Tuning (with large circular dial calibrated in wavelengths), volume, wavechange, Radio/gram., selectivity switch, tone (for records only), motor speed, on/off switch.
Loudspeaker : to in. m/c, in horizontal bass reflex compartment in lower portion of cabinet, with diffuser on front of cabinet operating both for loudspeaker and for vent of enclosure. Provision for 3 ohm extension speaker.
Cabinet : Massively built, finished in walnut veneer. 32 in. high by 31 in. wide by 18 in. deep.