Hey jonl,
I have used the Lehle Dual mainly in studio and it is a great unit. Lehle make some of the best switchers out there. Very reliable, well-built, easy to set, program, operate and control. However, if you plan using it live to split the signal in front of a Herbert and another amp running at the same time, and if you will be going through the amps channels in the same song, you may get phase cancelations when switching to channel 2 of the Herbert. Yes, the Lehle has phase inversion button but you need to switch it manually which obviously would not be very convenient on stage. I have asked Lehle if they can mod the Dual so it inverts the phase from distance via MIDI but they replied it wouldn't be an easy job plus a change in the design would be needed etc. which they are not keen to do and it's understandable. Another thing worth considering is that I noticed the Dual changes the sound, just slightly, but you can hear it. The sound is not as focused as it is without it in the signal chain. I have spent some time listening to make sure I wasn't making it up in my head. Therefore I ordered the RJM's Y-Not with the YB- (as in "negative") mod after some research. The difference between the two is that while the Lehle is a splitter and a foot controller in one unit, the Y-Not needs a separate foot controller to send commands to it. It is an additional cost if you already don't have one (and of course if you would be using live or when playing in a band and need changing things on the fly), however, the Y-Not doesn't change the sound, is as reliable and easy to operate as is the Lehle but with the advantage that now you can invert the phase at output B via MIDI and save it for future use. So, say you would be using channel 2 on the Herbert in combination with another amp you would no longer need to bend and manually switch it as it's with the Lehle. The Y-Not is absolutely great piece ot equipment and I have had no problems whatsoever for the past couple of years since I have it. I have been using it both live and in the studio. No problems at all. And as I said the sound is preserved as if you have been plugged straight into the amps.
Please, don't get me wrong. The Dual is far from being a bad choice, just the opposite, however, I wanted to let you know that it may not be the perfect choice if you decide to run a more complex rig when playing live or rehearsing with a band.
Hope this helps.
