Personally I’ve used spring water and tap water and not tasted much of a difference but our water here is not too bad, but not too good. I was intrigued by this discussion so I did a little search and found this article that explains the effects of Chloramines on brewing,
For those who don't want to read it,
"Chlorine can be eliminated in simple ways, such as simply letting it gas out of the water over time (usually overnight) or by pre-boiling the mash water. Chloramines are not as easily degraded. Chloramines will breakdown with the use of campden tablets, which will break the chloramines into calcium, water and bicarbonate. Failure to deal with chlorine or chloramines can result in yeast metabolizing these into harsh medicinal notes called chlorophenols. This is also true of using too much chlorine as a sanitizer
But I think the last point is vary important, if you use bleach to sanitize your equipment rinse, rinse, rinse... The chloine contaminaton from not adiquitly rinsing will be much higher than what will come from the tap...
just my 2˘
Keg1: Sour mash English Bitter
Ondeck: Honnymoon mead