my humble advice is to not rock the wah back and forth with the tempo of the song. Everybody does just that and it's a little tiring to hear any more. If you watch and listen to Jimi he uses it as a filter quite a bit...finds a 'sweet' spot and then slowly manipulates the pedal around that spot. you can use it to control feedback that way for really cool feedback solos...that's how I use it most often. Just my $0.02 ;-)

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