On Sun, 03 Aug 2014 13:52:35 +0100, "Dave Plowman (News)"
wrote:

In article 2,
DerbyBorn wrote:
On a similar vein I have sometime seen heavy metal bands use a mic stand
which has what looks like a plastic tube alongside the microphone. Any
ideas?

Vocoder?

As popularised by Peter Frampton on his 1976 hit, "Show Me The Way"