Astor KM - c.1946

This was one of Astor's first new models after the Second World War. Released in the second half of 1946. The model came with a reflexed superheterodyne 4 valve chassis. Astor claimed that:

The circuit which is of unusual design has overcome the disadvantages of reflexed circuits, i.e., low volume distortion and failure of the volume control to cut off.

The service manual goes on to say:

AVC is applied to the 6A8G (1st tube) only. Volume is controlled by varying the reflexed audio signal to the 6B8G tube (2nd tube). The audio output of this tube is fed directly to the 6V6G output tube. Degenerative feedback secondary of the transformer and applied to the bottom of the volume control. A second circuit providing bass boost is connected to a tap on the volume control. 

Unfortunately, the 6A8 and 6B8 tubes are now in short supply.

This model was followed by the KM in 1947 that has minor changes and sold in the many 1000's.

Example from November 2025.

I bought this cheap at a HRSA auction. No-one wanted it as it looked awful.

The cabinet was hand painted and the dial had had it.

I started to strip the hand applied paint back and there was another layer. This was factory paint. Underneath that was a pristine Walnut cabinet. However, there was a big blemish on the top. Obvious it had been painted at the factory, a practice used for reject cabinet pressings. Still if you don't look to closly.

The chassis - number 257 - was just a matter of a recap. Valves are weak, but it does work.

5 colours, 6 to go!

Page revised 1 Dec 2025