Yeah, I've been a little turned off on this pedal due to what I've read about noticeable signal loss (volume drop) when the unit is engaged. And others have reported signal degradation when the unit is just in the chain and not on. I've read it often enough to be concerned, and have also heard it in a couple of videos. Plus, it takes its own wall wart, and can't be powered by a boss-style adapter, of VS Onespot, which is just annoying to me.
As for tap tremolos that can be tapped when off, the only one i've found that I know can do that is the Empress tremolo, which has gotten rave reviews but is out of my price range. There are other tap trems, but I haven't found out yet if any of them can specifically be tappped when not engaged. I know the Seymour Duncan shape shifter cannot. There are some other random trems that can take an expression pedal, but it swells the speed or depth. It's not an expression tap. I wish the Line 6 MM4 had a tap, because that could be fun.
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