Piezo above the lid or under the hood

[sandy]

I have a couple of CBG's with a piezo under the hood, just jammed between the neck and the lid, it sounds OK but does pick up the odd knock and unmusical dunt.
I have seen CGB bridges with a couple of piezos embedded in them, they sit in the bridge and I am told they reduce unwanted sounds.
Anyone tried them ? is the tone better or similar?
Is it purely a matter of personal preference whether the piezo is above or below the hood?
Anyone got any thoughts on this ?

[huey]

Just a thought, but those pickups are pretty cheap, so the best quality is probably not to be had by them. However, placement could indeed be responsible for any knock. Finding the exact source of the knock is probably an exercise in futility though. If you had someone pluck the strings as you looked through any sound hole with a small automotive mirror or dental mirror, you may see something you could identify, but probably not. It could also be in the switch or even the chord plugs. Probably a hundred different areas, as well. If possible, you perhaps could stuff a small amount of thin foam around the neck where it enters into the box and at the inside back of the box where the inserted neck is, That may or may not help, but if it eliminates the noice, then you at least have a starting point to isolate it for yourself. You may also write to any CBG manufacturer for any tips they can share with you on finding the noise culprit. All of this is a guess on my part, as I am certainly no expert in the CBG field. I just joined this forum, so I know this is an older thread and the solution may already have been found. If it was, please let us know just what it was.