Finally had a chance to give the BDPG a workout at bar-band rehearsal last night. I have to say that it's a much different circuit than I expected! I was assuming that I would just hve a bit of Submarine style enhancing with added functionality, but the BDPG is so much more than that!
To my ears, the majority of the tone sweep provides a bass boost that is just perfect for firming up the low end. I was having trouble getting the low end cushion I prefer from my Aguilar AG500sc/GS212 rig, but that was solved by the BDPG. The effect is tuned just right and every note on the e and a strings sounded huge and three dimensional.
To my ears, the BDPG provides a tube style compression to the higher strings, which kind of drowned them out as opposed to making the notes jump out as it did to the lower notes. On the other hand, it made the bass gel and blend into the mix. So, for my applications, I would probably disengage the effect should I need to take a solo (rarely).
One question I have is about the gain range - I need to crank either the pre-gain or the volume (left and middle knobs) to get close to unity gain. Is this normal for the circuit? For example, my cleaner setting has the pre-gain at 9 or 10 o'clock, but the vol. has to be around 3 o'clock, which seems fairly cranked to me to be at unity. With both knobs at noon I was far below unity which seems unusual so I'm wondering if I maybe have a component out of speck.
Now, my caveat is that I haven't played the BDPG with my fEARful rig, which is much more accurate and revealing than my Aggie rig, so I expect to have to revise much of my opinion once I do so. I'm guessing that I'll have to use subtler settings on the BDPG in regards to the bass boost since the fEARful has so much more low end, but perhaps the compressing of the high strings will not be so prominent.
Overall, the BDPG is a perfect always on effect for a troublesome rig. It took my Aggie gear from, "meh" to "whoah!

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I'm also excited to get the BDPG on some recordnings and I have high hopes for that application. Once I get some tracks down, I'll put up some soundclips (probably late fall).