A 'foursome', a four-piece, mayebe... but you won't see many 'quartets' outside of jazz and classical. (Yes, I knew you were joking, Ian )

Here's the thing... When smaller and more different outfits started to take over from big-bands, they DIDN'T call themselves 'big-bands' or 'Orchestra's'. They gave themselves a new name, for a new type of music. They didn't glom onto the same name, in an effort to hoodwink the public into thinking they WERE going to see an orchestra. They were different, and proud of it. 'Combo's' and 'bands' were the name they picked.

The unwillingness of today's 'pro' karaoke, or OMB plus singers outfits to find a name for their type of performance style is telling, IMO... Do they think that, if described more accurately, or at least given a term that the audience would know what they are going to get, it would impact their popularity? Possibly not, but there's a definite unwillingness to differentiate themselves from 'real' bands, if you ask me.