are on this page
http://www.soundprofessionals.com/cgi-bin/gold/category/510/audio
Have fun!
PS FOr the most part, ALL of the built-in preamps on the "point and shoot" recorders are a little noisy - if you really want to fix that, run external mics and pre into a Line in. Personally I find the noise from the built-in pre's negligable, but ymmv.
PPS I personally HATE the menu system on the Zoom series, but maybe they've fixed it in later releases - the one I looked it was like menu-o-rama which, compared to the ease of the Edirol and Olympus interfaces was really cumbersome. The Sonys are probably the best sub-$500 recorder out there right now, but I'm hearing good things about the Tascam recorders, too.
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"If you only look at what you left behind youll never be able to focus on what lies ahead." - Gusteau