Reverse the order of those two sentences, and I think you have 90% of your answer.
Originally Posted by Rokket
I think most of it is simply that alchohol is an inhibition supressor and one has a tendency to get the ol' "courage from a bottle" when they drink beforehand. But that doesn't necessarily make them sound any better. And long term it's a bad idea.
I just did some quick searching of th Net on the subject, which seems to back that up. Here's the first three results I got:
From The Acoustical Society of America:
Experiments to determine the physical effects of alcohol on the human voice are reported. Recordings of sustained phonations and prescribed texts were taken from 12 volunteers at various stages of alcohol consumption, to determine whether a significant change in voice frequencies occurs when alcohol has been consumed. No association between the fundamental frequency of a sustained phonation and level of alcohol consumption is observed (regression coefficient=0.146, t ratio=0.28, df=71, p=0.781). Similar results for the higher formant frequencies are also observed. The effect of alcohol on duration of speech is also investigated. Prescribed-text, sentence duration is found to increase at the rate of 6.4% (standard error =0.5%, p<0.0001) per ml of alcohol consumed per kilogram of body weight. There is no evidence that the sex of the speaker is related to the effect of alcohol on sentence duration. Acoustic analysis of fixed-text voice recordings is therefore not a suitable method of determining whether a person is alcoholically intoxicated. [This research was supported by the Research Committee of the Royal College of Surgeons in Ireland.]
In moderation it’s OK. Alcohol is very drying, it tends to help to increase acid reflux, and the third thing is, especially while onstage it can inhibit the sense of perception… Most performers who have performed while intoxicated and then they become sober, are almost embarrassed by the fact that they used to think they were more creative and performed better while they were intoxicated onstage. And every single one of them--and these are great performers—said that they do much, much better when they do not have anything like alcohol inhibiting them onstage.
From the Drug and Alchohol Resource Center:
Heavy drinking can increase the risk for certain cancers, especially those of the liver, esophagus, throat, and larynx (voice box).