What do the Weird Sisters sound like?

[Alicia]

No: HPFGUIDX 53655

The Weird Sisters are "a very famous musical group" who cause "wild 
excitement" when the students learn they are coming to the Yule Ball 
(GOF, ch 22). The band members are "all extremely hairy, and dressed 
in black robes that had been artfully ripped and torn" (GOF, ch23). 
They have a "lead guitarist" named Kirley (QTTA, p36).

So far, so typical rock band. But...

Their instruments consist of "[a] set of drums, several guitars, a 
lute, a cello and some bagpipes" (GOF, ch23).

We know that electricity and magic don't mix, so those guitars aren't 
electric. They don't need amps anyway because sound can be "magically 
magnified" (eg McGonagall's announcement, COS, ch16).

Personally, I think The Weird Sisters are band with a name, an image 
and a lead guitarist, rather than a loose collective of musicians who 
occasionally get together for fun, so they seem to have used some 
ideas from muggle rock, such as presentation and marketing. I also 
imagine they would be using the scales and musical forms we are 
familiar with, nothing atonal or experimental - they seem like a good 
band to have at the Yule Ball. I just have the feeling we might think 
they're more of a folk band. I've just been to a folk festival, and 
some of the acts had me wondering.

So my question is: what do other people think The Weird Sisters sound 
like?

Alicia, who thinks Celestina Warbeck would sound like the WW Celine 
Dion.