After much positive feedback regarding this pedal, I decided to buy one myself to see how it would work for me. I've been looking for a boost to run through my SV20H's effects loop to give a volume boost for soloing (I'm now realizing this is impossible based on the amp's design). I was using an EH LPB-1 but was interested in the three boost "voicing" of the Spark. I found that it does add a great extra kick for soloing but doesn't really add volume. However, I ran across an interesting situation at last night's band rehearsal. I use a Fender Bassbreaker 30r at my rehearsal place. When I use the LPB-1 in the effects loop on this, I get the volume boost I'm looking for without further coloring the tone. However when I used the Spark, not only did it color the tone (regardless of which voice setting I used) but the volume was very noticeably cut. I had the level fumed on the pedal and it was still significantly quieter than if I had it turned off. It isn't a battery issue, I'm powering it with a MXR DC brick. This was a huge disappointment for me and, had it not sound so great as a lead boost in my SV20H, I'd strongly consider returning this. Any thoughts on why it reacted so differently in the Fender?