|You may suffer some signal degradation if you split the signal to that many TV's, without using a signal amplifier.|
I am a karaoke host (3 nights/week) and I use two TV's and an LCD data projector. I can barely get away with this setup (slight loss of picture quality), without the need for an amp.
Having said that, I have noticed that one of my TV's has multiple composite-out connections. If I daisy-chain a second TV via these outputs, I get no significant loss of quality.
The best approach would be to add one TV at a time, until you begin to notice signal degradation.
A little loss of picture quality may be acceptable if you use only CD+G (CD+Graphics) karaoke files. Quality loss will be more crucial when using VCD's (Video CD's).
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