Geoff, actually the Number Cruncher was an Entec product, Demian Martin's company. Bob was merely a big fan of it and came up with some worthwhile modifications of it. The CTC modified version of the Parasound HCA3500 amp was the BBQ, never spelled out, but its performance was eclipsed by the Parasound Halo JC 1 monoblocks, which the CTC team designed.
As for TG, indeed it stood for Throbbing Gristle, the name of an industrial rock band. But the name reverted to just TG after an important customer's wife became incensed upon learning what TG stood for.