I'm wondering if anyone has any experience with the following patient:
A Gretsch model 6176 fretless semi-acoustic bass. Customer brought it to me advising that 2 of the strings are not coming through the pickup. The saddle had an obvious split dead in the middle, which when you run your nail over you can feel a small bump-the 2 pieces were slightly out of plane. We figured that was why the 2 strings were not being picked up- the saddle had split and wasnt contacting the pickup evenly (it is a under-saddle one piece p/u element). Upon removal, I see that there are clear signs the faces of what would be the split are actually worked-its not a split at all. It appears this had a split saddle all along.
So, if replacing, do I make 2 split saddles, or should this have been a single saddle? I do have a chunk of bone large enough I could re-do it in one piece, but wondering if there was a good reason for this other than finding a chunk of bone large enough is a bit tougher?
It's not the saddle which is the problem, if it is sound why would you replace it? - it is a split saddle and should bear down better than a single piece unit. The problem lies elsewhere - maybe the bottom of the saddle slot under the transducer is distorted or uneven, maybe the pickup element is crushed or uneven, maybe a saddle section is binding in the slot.....all the usual suspects. Try putting a shim under the saddle unit that is not in contact. Do you have a spare transducer you can try (essential troubleshooting item for this kind of stuff) or can you swap the transducer end for end (even if you have to drill an additional hole at the other end of the transducer/saddle slot) and see if the problem goes to the other two strings - which will help localize the problem.
This may not be the answer you are looking for but if it were me I would try a piece of ebony or Maple in it first be for I spoild a good piece of Bone .At least that should tell you if that is the problem or not .Bill..............
I should clarify- once the string tension was off, the saddle pieces are narrow in the slot and they have a fair bit of play front to back in the slot- thats not gonna help transducer response, so my reason to consider replacing. May be the root of the p/u problem itself. It looks to me the saddle fitted well once and maybe the bridge has just dried up & shrunk a bit over the years? I wish I had another transducer like this to try but its a big fat bass thing & nothing like that hanging around here. I agree Rusty I assumed two piece saddle would bear better? The pickup element and the saddle bottom both look real good, no signs of damage or bad tinkering.
Thanks Rory, good info.
If the saddles are skinny they tend to lean over towards the peghead end when under tension and only bear on the transducer with the leading edge of the piece of bone or whatever the saddle is. They can also literally "wedge" in the slot and not make contact (much) at all. The saddles should be a sliding fit and have as much, or more sadddle in the bridge slot as is exposed out of the bridge (or thereabouts - rule of thumb) - this helps prevent the tilting and ensures good contact. Fishman used to have a good installation/instruction sheet about this stuff if you have one.
Now, a rudimentary test of whether the transducer works is: destring it, plug it in turn up the gain a bit and place the saddle pieces in the slot and put even pressure on the saddle with your thumb in the vertical and lightly (LIGHTLY) tap the saddle or the back of your thumb - repeat for the other end using the same pressure - if the output (which should be a thump sound) is pretty much the same you probably have all the crystals (assuming an old style piezo transducer) working. This may help localize the problem. Forgive me if I am telling you how to suck eggs here - not the intention. Rusty.
Rory , you might want to check that the strings are contacting the saddle with a good break angle too , the double windings at the ball end can sometimes hold the string up off the saddle . A shim might pack in along the saddle too to make it stand up straight.Len
The under saddle pups are a little finicky and often individual string volume varies considerably. Some under saddle manufacturers recommend cutting the saddle in half in an attempt toget even volume from each string. In these cases, I make a one piece saddle, fit it to the slot & correct height to get the action where the customer wants it and then I take it out & cut it inhalf.