As a more classically trained singer who is enjoying singing traditional music, I'm interested in this whole vibrato issue. Vibrato can add warmth and fullness to a voice without detracting from its purity. I have a friend who was raving about a singer who sang with a nice straight tone. This singer actually has a vibrato but the voice is still very clear and pure. People tend not to notice the vibrato but it is still there.

When people say they don't like vibrato, I bet mostly what they mean is they don't like a wobble which is too wide a vibrato. Or a tremolo which is too fast a vibrato.

I've just been to an early music workshop and I asked the very knowledgeable director about vibrato in early music. He did not think all early music needed to be sung straight tone, that much of it was written for castrati who would sing with a vibrato.

I like to think that people are singing with the best possible sound they can make, vibrato or not. And the listeners will appreciate that.