Mary uses a Sennheiser G2 100 radio headset. It's UHF, while most of the cheaper ones are VHF, which means it's less likely to interfere with others in the locality. It can be set to hundreds of different frequencies but I've never had to change the original setting I programmed in, which was chosen to be legal for unlicensed use in the UK.

The sound is excellent, and it's always performed flawlessly.

We got the idea from Dave Webber and Anni Fentiman, who use AKG headsets that didn't cost as much as Mary's but had worked well for them when we saw them.

You can mute the transmitter if you want to speak unamplified.
A big advantage for Mary is that she can talk, e.g. introducing the next song, while turning around, putting down one instrument and picking up another. Not having a mic stand in front of you makes a big difference to communicating with the audience too.

The whole radio mic spectrum is under threat of being sold off, to digital TV in the USA and I'm not sure where in the UK. It's madness: radio mics are used all over the entertainment industry, in theatres, radio, TV and pop concerts, sometimes over 50 mics at the same event. And by a few folkies as well....

You can get some of the advantages with a headset mic that's wired direct to the PA (no radio), but you have to remember that you're tethered by a cable: not to wander about and wrap it round mic stands and other paraphernalia on stage (or round yourself) and to unplug it it when you walk off at the end of the set...

Anahata