View Full Version : Mandolin bridge height compensation?
Robin R
Aug-14-2017, 12:23pm
Greetings, we just started a new group and although I've played guitar for 40 years, the new song list includes a number of tunes that include banjo and/or mando. With our first gig approaching in two weeks (a winery), I decided to see if I could find an inexpensive electric mandolin. I found a Fender FM-52E is beautiful shape with a nice hard-shell case for $100). I got onto the mando tuning easily enough but thought the action was high.
Checking the setup, I noticed that the bridge base was significantly higher on the bass side (1/8" or so higher than the treble side). I see that mando bridges offered by StewMac and others do not have any "bass side compensation" so I decided to trim the bridge bass down a bit and see what happened. It plays much better now with no buzzing or rattling, but the bass side is still higher than the treble side. The neck is flat (no radius) but I can see that the bass strings still high. Should I rework the bridge base to eliminate the "compensation" all together? I'll still able to adjust the saddle height with the thumb wheels on the bridge. Thanks for your help and advice.
Robin
It's not uncommon for the action to be a little higher on the bass side. However, it's also not uncommon for cheap mandolins to have a terrible setup ;)
So yes, you can keep lowering the action till it buzzes, then crank it up a touch till it's clean again.
colorado_al
Aug-14-2017, 4:24pm
Also possible that the top is sinking on one side. However, exactly why the bridge is adjustable.
sblock
Aug-14-2017, 5:06pm
Yes, I, too, am inclined to think that the bass side of the top might be slightly lower then the treble side. This can happen if the top is sinking differentially, in which case you might want to keep an eye on it, to see if it worsens or is completely stable. But it can also happen if the entire neck is mounted at a slight angle with respect to the top (looking down the fretboard), or if the top has been replaced (and does not lie completely square on the old body), or if one of the bridge's base feet has been sanded down a bit more than the other during fitting. It is not necessarily anything to worry about. If it's one of those last three things, just adjust the saddle as necessary and don't worry any further about it.
Mandoplumb
Aug-14-2017, 5:23pm
Everything said is true and could be the explanation, but what does OP mean the base side has no compensation? Are we answering his question? Compensation for height? Adjustable or fixed bridge? Maybe I'm dense but that statement leaves me wondering.
Robin R
Aug-14-2017, 5:29pm
Thanks for your reply's, I visited a friend's shop today (http://www.tillguitars.com/), he is just starting to offer electric mandolins and they are very nice.
He showed me some mando bridges he had on hand and none of them had had any compensation from the bass side to the treble side.
I checked my mandolin again, the neck is straight and the top is symmetrical (from bass side to treble side). Only the bridge bass side is higher than the treble side. I'm going to even it out and set up the bridge with the thumbscrews. Thanks again!
colorado_al
Aug-14-2017, 7:18pm
It sounds like you have a handle on it. I'd recommend getting a copy of Rob Meldrum's mandolin e-setup book. It'll help you get the best out of it.
Check out this thread for instructions on how to get the setup book
https://www.mandolincafe.com/forum/showthread.php?113246-All-Praise-Rob-Meldrum!
sblock
Aug-14-2017, 7:18pm
Thanks for your reply's, I visited a friend's shop today (http://www.tillguitars.com/), he is just starting to offer electric mandolins and they are very nice.
He showed me some mando bridges he had on hand and none of them had had any compensation from the bass side to the treble side.
I checked my mandolin again, the neck is straight and the top is symmetrical (from bass side to treble side). Only the bridge bass side is higher than the treble side. I'm going to even it out and set up the bridge with the thumbscrews. Thanks again!
Huh?! Virtually all mandolin bridges made from the 1910's to the present day -- over a century! --
come with compensation on their saddle. And most of these are height-adjustable, too (not all) -- but that is something entirely different. Could it be that you are confusing the words "compensation" (a forward-back adjustment, parallel to the fingerboard) with "height adjustment" (an up-down movement, perpendicular to the fingerboard), I wonder?! If so, please get the terminology straight!
I find it pretty hard to believe that your friend's shop sells uncompensated mando bridges, unless their saddles are only partly carved and awaiting the extra carving for compensation upon installation. Nearly all mandolin saddles require some compensation for proper intonation up the neck. It's especially important on a short-scale instrument. And that holds for electric mandolins as well as acoustic ones. One additional word of advice: don't seek the advice of an expert on electrical instruments when it comes to adjusting an acoustic instrument! A Fender FM-52E is an inexpensive acoustic mandolin body with a pickup; it is not a solid-body e-mando. It needs a compensated bridge. And a height-adjustable one.
Anyway, it is not at all unusual for mandolin players to set their action (this is the height adjustment, and it is NOT to be confused with compensation!) a trifle higher on the bass side than on the treble side. On my F5, for example, the treble side action is close to 55 thousandths of an inch (measured at the 12th fret), whereas the bass side action is approaching 60 thou. This involves setting the height adjustments on the thumbwheels somewhere between 1/16 and 1/8 inch higher on the bass side. As you can see, the bridge saddle does NOT need to be perfectly level with the fretboard for a great mandolin setup. On the contrary! There are two thumbwheels for a reason.
Huh?! Virtually all mandolin bridges made from the 1910's to the present day -- over a century! --
come with compensation on their saddle.
sblock: I think you have hold of the wrong end of the bridge here ;) The OP had a bridge that is higher on one side than the other, the word "compensation" is a misnomer in this context, and yes I'm sure he has the form you're thinking of as well as a lopsided bridge!
sblock
Aug-15-2017, 11:11am
sblock: I think you have hold of the wrong end of the bridge here ;) The OP had a bridge that is higher on one side than the other, the word "compensation" is a misnomer in this context, and yes I'm sure he has the form you're thinking of as well as a lopsided bridge!
I think that was my point. This is not about compensation; it's about height adjustment. And it's perfectly OK for the saddle not to be level with the fingerboard, with the action raised slightly on the bass side. I would not describe that as "lopsided." I would describe it as normal!