avoid vibrato. I can't imagine it would work well unless the other parts can keep in time
Excellent observation. Definitely avoid vibrato, it can only lead to trouble.
What J Haley said about vocal practice is exactly what is needed. The band I mentioned that recently recorded Southern Cross did exactly that. I would grab an acoustic guitar or turn my electric down to acoustic volume or lower, and we would spend at least a half hour out of almost every band practice working on harmonies. Especially when first learning a new song. That is a must, you can't come across with good harmonies onstage without practicing it beforehand.
You have to each know exactly what part you have to sing, when to sing and when to drop out, and how to equalize your volume level with the other singers.
Anyone in the band who is not singing also has to be patient and QUIET while vocal practice is going on. I almost got into a fight with our other guitar player (who was fired later) because he left his amp cranked up to stage volume and kept doodling while we tried to work out harmony parts. I finally told him shut up, he said he needed to practice. I told him - well yelled, actually - practice at home...which he never did. It almost escalated into a a fight but the other vocalists backed me up and told him we couldn't hear what we were trying to do with him playing LOUD...he finally got the message and shut up, but it cost us a useless day of rehearsal, since everybody was pissed from there on and we quit early because we were getting nothing done.
If you have trouble hearing yourself you can put your finger in your ear, press the little middle flap closed. That will let you hear yourself much better. I remember seeing the Bee Gees on TV as a kid, and one of them always did this. I always wondered why until I found out by accident one night. He couldn't hear himself so he had no idea whether he was hitting the right notes. That was also my signal to my sound man years ago that I needed more monitor. Unfortunately it also means you have to stop playing guitar...
This is where a good monitor system is worth its weight in gold too. Onstage the ability to hear all the vocals well is critical. If you can't hear the vocals, the harmonies will suck.
OK I'm going to drop in a shameless plug here. Since I've mentioned Southern Cross a couple of times, here is the thread. Give it a listen if you haven't already. After 10 years not seeing each other we can still harmonize this well with no practice, just a quick run through. If we had spent a half hour working on it, and we should have, we would have been able to nail it with no trouble...that's what you get for getting in a hurry...
http://forum.bandmix.com/viewtopic.php?t=18315
I think it was Paper Dog who first noticed the harmonies were a bit off on the first chorus. I'm not sure which of us it was, but it was corrected pretty quickly. This is where hearing yourself is critical. But when you hear all 3 vocal parts, it's not as easy as you may think to pick out which one is YOU...I was really surprised when I first tried it onstage and found out how difficult it was to determine my own part, even with only two singers. That's why vocal practice is critical.
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