Gibson ADJ Bridge Replacement
 

I'm very close to purchasing a late 50s Gibson J-45, but it has the dreaded ADJ bridge and saddle. I know lots of people like the ADJ bridge, and sometimes I do too, but in general I much prefer the tone of a classic bone saddle. I know this mod will make the guitar "unoriginal" but I don't really know of any serious guitar collectors who collect ADJ Gibsons.

My question is what should I expect to pay to have this modification done? I know some people simply put a rosewood insert in the ADJ bridge, but I can't help but feel the tone would be much better with a full on replacement of the bridge. Can any owners attest to this? Thanks!

I own a 1964 Gibson J45 that has an adjustable bridge.... I would NEVER change it! The sound is heavenly! Don't prejudge the adjustable bridge....If the guitar sounds great, simply accept it.
Boneyard

My $.02
 

I have a 1962 Gibson B-25 that had the adjustable bridge. I had it replaced with a Brazilian rosewood bridge and bone saddle. Sounds much better. The adjustable bridge was plastic, bolted on and was lifting off the soundboard. It did have its own cool tone vibe but the new bridge definitely sounds better. A J-45 is definitely more collectible so altering it may affect the value but that’s a mod that wouldn’t bother me if I was considering buying it.

Rex, I have never had the work done, having never owned an adjustable bridge Gibson. But having the bridge swapped out for a conventional acoustic guitar bridge will remove a LOT of weight from the bridge area. Every time I've been able to make a before and after comparison with other people's adjustable bridge Gibsons, the tonal improvement after the conversion has been significant.

Here are some photographs from Frank Ford's Frets.com website to illustrate why:

Here's the Gibson adjustable bridge:


Here are the parts that make up the operating mechanism:

As Frank puts it, "The whole business together tips the scale at 65 grams":

"While a complete conventional nonadjustable bridge weighs in at 23.3 grams":

Frank concludes that part of the webpage by writing:

"I generally don't recommend hotrodding instruments, especially when the results are subtle to the degree of being just marginal. But any time you can reduce the mass of an overweight bridge by two thirds, you're bound to be able to notice the improvement in volume and tone."

Here's the link to that page of Frets.com if you want to read the entire page:

http://www.frets.com/FretsPages/Luth.../hbirdbr1.html

Now, there are those who love the sound of adjustable bridge Gibson acoustic guitars, with Boneyard75 - who's already posted in this thread - as a perfect example. If you're mainly interested in this guitar as an investment, then I think you'd be wise to heed his advice, because you will devalue the guitar somewhat, at least so far as those potential future buyers who love adjustable bridge Gibsons are concerned.

But if your primary concern is tone and volume, then, yes, getting it converted is well worth doing. As Frank stated, any time you can cut two thirds of the weight off an acoustic guitar's bridge, you're going to hear a definite, audible improvement in tone.

As for what the work will cost you, that's going to depend on where you are and who you have do the work. But my guess is that it should be in the $250 range, give or take $50. It's not a major repair, but it's not a half hour job, either.

Hope this helps.


Wade Hampton Miller

Check out this simpler option in post #11 and #12 on this previous AGF thread covering this same topic.
https://www.acousticguitarforum.com/...d.php?t=441699

Good alternative, and probably won't cost as much to execute. There'll still be some metal in the bridge left over, but not as much.


whm

Really appreciate this, Wade. That article is exactly what I've been looking for.

Happy to help.


whm

Only Gibson I own that is near new enough to have an ADJ saddle bridge is a 1961 B45-12. Not only would I not think of rolling the bridge but prefer the sound with the guitar's original wood saddle to that of the bone replacement I tried.

If you are determined to go with a fixed bridge there is something else you need to think about which is the bridge plate. Gibson went with an oversized laminate plate to support those heavy bridges. The stiffness of the plate strangled the energy being transmitted through the bridge. This is, of course, assuming that Gibson used the same bridge plate when the ADJ saddle bridges were optional as opposed to standard which I do not know. But I believe the bridge plate is more to be dreaded than the bridge itself.

Removing the bridge plate, installing a new one, making a new bridge and saddle and setting up, as shown on Frank's page to which you linked, is likely to be considerably more than the $250 range that Wade suggested. I'd estimate it twice that.

I have a '62 J45 (which is up on Reverb, wink wink) that my luthier was reluctant to remove and replace the existing bridge on because it was so firmly attached. The solution was to remove the adjustable bridge and metal hardware and then to fit a custom bone saddle that fills that entire slot and sits flush to the top. It definitely changes the sound, IMO to the better--a little more volume, a bit more depth in the mids and trebles. The bass always boomed on it, so I don't know that the new saddle made that much difference. So there are definitely other options that total conversion, especially if you want to preserve the ability for future players to revert to the original ceramic bridge, which does have a specific and pretty darn good tone all its own.

Here is what I made.
I contacted Tom at Alvarez, and he told me I called just in time. He said I had purchased the LAST 6 original Alvarez adjustable inserts. I decided to save them, and replace the adjustable saddle with a fixed one.
I made the blank insert from ebony as close to the size of the adjustable saddles original hole on the bridge. I then milled the saddle slot. Then sanded the ebony insert to fit snugly into the bridge space, but not too tight or too loose. NOTHING is glued in place. I feel thew guitar sound a bit better. Plus I feel the insert added to the look of the Guitar. Someday I plan to make another on that more closely matches the bridge wood. The Guitar is a Alvarez 5024 Knockoff of a Gibson Dove. Not a Gibson but stands well on it's own merits.
When I got the guitar the pickguard was in pieces, and once I got it back together I noticed a piece was missing. I repaired it as best I could as that style pickguard is impossible to replace. There are cheap reproductions but the originals are transparent.


Ed

https://hosting.photobucket.com/albu...370&fit=bounds

https://hosting.photobucket.com/albu...370&fit=bounds

https://hosting.photobucket.com/albu...370&fit=bounds

https://hosting.photobucket.com/albu...370&fit=bounds

https://tinyurl.com/y23var7l

https://previews.dropbox.com/p/thumb...ue&size_mode=5


https://previews.dropbox.com/p/thumb...ue&size_mode=5

https://previews.dropbox.com/p/thumb...ue&size_mode=5

ADJ bridge
 

I had a 65 J45 NAT ADJ, natural top with the deservedly maligned adjustable bridge. It was a tone and sustain thief.

But, like you, I was concerned about keeping the guitar "original".

The solution was similar to what's shown above. I removed the accursed adjustable section, cut a hardwood insert that fit the slot left in the bridge, slotted it for a "standard" saddle and got back to playing.

The improvement was like night and day.

Plus, when I sold the guitar I included the old ADJ parts and it would be a simple matter to put them back in, if that's what they wanted.

There's no reason to replace the entire bridge.

Just my less than humble opinion, YMMV.

Let us know what you decide to do.

Appreciate this, Athens! This is partly what I was curious about. Good to know removing the ADJ parts and using an insert improved the tone. This is probably the route I would go. I'm also looking at a very similar J-50 with an original traditional bridge and saddle, but there's something about that sunburst...

Another thing I heard from a luthier friend is the ADJ bridge has a plywood bridgeplate on the underside of the top. Whereas a normal bridged Gibson would have a solid maple bridge plate. He recommends replacing the bridgeplate too. Then you get the complete tone that the non-ADJ guitars have.