Mine was a transistor 30W 2x12" Marshal Lead Combo like this one.

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I used my Ibanez TS808 on a low volume to provide the rhythm setting and then turned it off for lead, in order to get a decent volume boost. For a 30W tranny amp, it was pretty loud, and for a mid-late '70s tranny amp, didn't sound that bad. And it wasn't too heavy, which was good, as I sometimes had to carry it about 1/2 mile to rehearsals when I was at Uni, on a pretty hilly campus.