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View Full Version : Under Saddle Pickup problem.



kohanmike
08-25-2014, 04:50 PM
Not sure where to address this issue, so I'm posting here. I have a uke with an under saddle piezo pickup that was not installed properly, the volume balance is way off. The hole for the pickup wire is too close to the G string so when amplified, the volume is too high on that end and trails off to almost nothing from the A string.

My first thought is to just drill a new hole further away from the G string, but I don't know how the existing hole will effect the sound. Another thought is to drill a hole on the A string side (away from the string), but there will still be an existing hole the pickup will cross over.

Anyone have experience with this situation, and are either of my remedies viable?

paw123los
08-25-2014, 10:56 PM
I had the same problem recently. I took my instrument to luthier and he drilled a new hole but filled the old hole with the same material as the bridge is made of (rosewood).

PhilUSAFRet
08-26-2014, 04:51 AM
Good question for "Tech Support"

Rick Turner
08-26-2014, 05:02 AM
This is one of those issues that is pretty difficult to diagnose over the Internet.

Unfortunately, not many luthiers...or factory installers...really understand how pickups work. It is supremely important that each string press down equally on about the same length of pickup. Think of each string as being the point of a pyramid. The base of each "pressure pyramid" needs to be the same length. The fit of the saddle has to be a "slip fit", and the bottom of the saddle has to be perfectly even as does the bottom of the saddle slot at that pyramid foundation line.

Don't go drilling more holes in the saddle slot unless you really know what you're doing.

Take it to a luthier who specializes in pickup installation.

Where are you located?

kohanmike
08-26-2014, 10:07 AM
Take it to a luthier who specializes in pickup installation. Where are you located?

I'm pretty adept at this stuff, I've installed pickups in a couple of my other ukes that work just fine. But I do have a very good luthier, Fren Asken not far away who I've used, but he's so busy that it could be a couple of months before he'll get to me, he has clients/pro musicians who's needs definitely come before mine.

Rick Turner
08-26-2014, 12:09 PM
For the best undersaddle installations, here are a few tips:

1) The bridge saddle slot, and thus the saddle should be tilted back at about 8 degrees so the pressure vector from the strings breaking over the saddle is really down at the pickup and you don't have a lot of forward lean and pressure on the front wall of the saddle slot. Yes, I know this takes a specially done saddle slot, but this is how to get great results.

2) The saddle should extend at least half the distance between strings at each end, plus enough to take care of the "dead" are of the pickup where it pops down the hole in the slot into the instrument.

Really, it's best to have a bridge designed for under saddle pickup mounting. Such bridges also carry some acoustical advantages...they're stronger and it's less likely that the front of the bridge will collapse or the bridge split at the slot ends; and they automatically correct for minor intonation differences if you raise or lower the action. Then there's the huge plus of them working better with UST pickups.

BTW, I've got about 25 years in designing piezo pickups and another 20 on magnetic pickups. Been there, done that...

kohanmike
08-26-2014, 02:06 PM
I drilled a hole in the opposite end, outside of the A string and now the A string is much louder and the G very low. Could that mean the pickup itself is faulty? I'm going to use a different pickup and see what happens.

Dan Uke
08-26-2014, 02:11 PM
I drilled a hole in the opposite end, outside of the A string and now the A string is much louder and the G very low. Could that mean the pickup itself is faulty? I'm going to use a different pickup and see what happens.

Chuck has stated the tip of the strip is typically weaker so you make two holes and stick about 1/2" through the 2nd hole, which should improve the signal.

FrankB
08-26-2014, 02:38 PM
BTW, I've got about 25 years in designing piezo pickups and another 20 on magnetic pickups. Been there, done that...

Hi Rick,
I mentioned this back on the old AG Classical Corner, but I was knocked out of my sonic socks the first time I played your Renaissance guitars (both nylon and steel). All the acoustic-electric guitars I had played until then were quacky. Your design was completely natural, and that was back around 2002-2003. I was this close to buying one, but never did. Like the Santa Cruz OM PW I was about to buy, but didn't. Both are now twice the price. So buy Rick's instruments now, and take his advice. ;)

There's a really cool video tour of Rick's workshop, but I can't find it at the moment. It's about 25-30 minutes long....I think.

kohanmike
08-26-2014, 03:43 PM
Chuck has stated the tip of the strip is typically weaker so you make two holes and stick about 1/2" through the 2nd hole, which should improve the signal.

That's sounds like a good idea. I'm going to try that now that I have two holes.

l3uffer
08-26-2014, 06:28 PM
Brad at USpace should be able to help you out if you wanted someone to check it out... he's installed tons of Baggs 5.0s, so he knows pickups well and although he might not be at USpace all the time (he transitions between Anacapa and USpace within the week), Wednesday should be his for-sure USpace day!
Good luck with the troubleshooting!

Rick Turner
08-26-2014, 06:53 PM
True enough re. the ends of some (note the "some") pickups not being sensitive. We drill a hole at about a 30 degree angle at the end of the saddle slot opposite the end where the pickup goes into the instrument and we tuck 1/8" to 3/16" of the end of the pickup there. This keeps it in place and also assures that what the saddle is pressing on is all pickup.

Once again, even pressure is absolutely necessary, and too many saddles are really too short to do justice to the end strings whether thats 1 & 4 on a uke or 1 & 6 on a guitar. At this point we've installed literally thousands of under saddle pickups, and we've dealt with all the problems. We don't have problems anymore because of good bridge design and an understanding of the basic principles of how these things work.

Thanks for the comments on the nylon string guitar. BTW, I use exactly the same pickup for everything from ukes to acoustic electric basses with guitars in between. Same pickup, maybe different lengths, same on-board electronics. Very minor EQ...maybe just a hint of a bump at 100 Hz to emulate the air resonance of a typical acoustic guitar...but no more than 3dB. From my point of view, if you can't make a pickup that sounds good without EQ, you should go back to the drawing board. EQ isn't going to fix it. You might enhance it, but there's no fixing something that doesn't sound right.

I am working on a new acoustic pickup system right now; at first it's going to be for banjo; then I'll see if I can adapt it to ukes, mandos, and guitars. The initial tests are incredibly positive; this thing sounds great; it's as good a first prototype as I've made of anything I've done. I'm applying for a provisional patent this week. Stay tuned.

kohanmike
08-26-2014, 08:55 PM
Brad at USpace should be able to help you out if you wanted someone to check it out... he's installed tons of Baggs 5.0s, so he knows pickups well and although he might not be at USpace all the time (he transitions between Anacapa and USpace within the week), Wednesday should be his for-sure USpace day!
Good luck with the troubleshooting!

I had Brad install a pickup in a low end uke and he also worked the bridge saddle space, but it didn't help much, so I gifted it to a kid just learning. I want to try and do this myself right now, but if I can't get it, I'll have to get pro hands on it.

Rick, thank you very much for all your input, I really appreciate your expertise.