now your taking me back a bit guys, although very much the poor relation I do have a BSR tape recorder in the bottom shed, I can mention it here as it's got the Birmingham connection ( Birmingham Sound Reproduction IIRC ).
I take it by "tube" you refer to glass valves, a few years ago as a retirement present to myself, I bought a guitar and amp, took advice from the guy in the shop and came away with a Strat (type) guitar and an amp which he claimed was a good one because it had a "tube", and advice to start with no more than fifteen minutes a day (till fingers harden).
Well I'm yet to find time in this so called retirement due to bikes , kitchens, garden, U3A and so forth but one of these days I'll get to it - neighbours beware