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I just replaced the rosewood adjustable bridge on the archtop that I completed last November with a two footed, non-adjustable bridge made out of black locust. It’s just something that I quickly made to see what black locust might sound like. The rosewood one is pretty much based on the one in Benedetto’s book; two-piece with adjustment wheels on threaded pins. Wow,Big improvement! Louder with much more depth.
I’m not sure whether to attribute the improvement so much to the wood as to the design. I’ve always been skeptical of those little pins transferring the full spectrum of vibrations to the top. Have others found this to be an issue?
Of course the bridge on an archtop is adjustable for good reason. The top moves from season to season and from one gauge of strings to the next. So, If having a non-adjustable bridge significantly improves the volume and tone, would it be better to have an adjustable neck tilt mechanism to make those minor changes in string height? I know I’m not the first to think about this. Ken parker has come up with a very unusual hi-tech solution to this. Are there other luthiers who have designed adjustable neck tilts with fixed bridges for this reason? I’ve been doing some sketches and have figured out a bolt-on neck design that allows for tilt adjustments, but before implementing it on my next guitar, I thought I would get some other opinions on the matter

Herman Hauser did over 100 years ago and I've posted pics here if you search on Hauser of one we keep singing. He used a large, clock type winding key to adjust the neck angle.

More recently Fender has micro-tilt necks that have some angle adjustment in the design.

Lots of folks though the years have made adjustable neck angles just most of them never amounted to anything notable so we don't hear about it.

Locust is a great wood for a bridge and for bridge plates too, resonate, tenacious and not your usual choice so you are not competing for limited supply with anyone.

Adjustability especially adjustability on the fly say at a gig is important on an arch top for a gigging musician. There is a reason why the thumb wheels don't require tools to adjust.

My suggestion to you is to make a traditional arch top bridge from locust with pins and thumb wheels. Fit it very precisely to the top and my guess is that the material, locust will have value to you tonally even with pins plus you have adjustability.

Also check out Faber USA for a source for fine German steel pins and wheels. They supply parts to Les Paul upgrade folks but the pins and wheels can be used on an Archie bridge. Great stuff. I've got Faber on a number of my axes.

Just learned "Almost cut my hair" today since I've been self-stifled at home now for 21 days.....

Thanks Hesh that’s more or less exactly what I drew in my sketch. Are there any problems with this design?

this swap made a huge difference. 2 foot all rosewood to a fitted full contact with a bone saddle. Also the new bridge ended up being adjusted all the way down with the saddle portion in full contact with the foot. Too many variables to say what was the main factor. I can only say the improvement was dramatic

So, essentially that’s like a fixed bridge. That may be reason for the improvement. Try raising the bridge a little and see if it still sounds as good.

I don't think the adjusting wheel screws would make a difference in the sound, except, of course, for their mass, so long as they're done right. Often they're not. THe trick is to get the screws at an angle that bisects the break angle of the string over the bridge. This eliminates the tipping force at the bridge top, so the screws are not trying to pry the bridge bass apart. This is especially important with the usual tiny screws. Also, I really like using a bigger thumb wheel that gives enough leverage that you can actually adjust the bridge without having to slack off the strings.

Jim D'Aquisto came up with a nice height adjustment that I've been using on archtops. The bridge base is solid with a slot for the saddle, and a wedge between the saddle and the base allows for adjustment of the height. You can't adjust the treble and bass sides independently of each other, but that's not usually an issue. If you're careful about getting the bottom of the slot nice and flat, and all the surfaces of the wedge and the saddle bottom likewise, you've got perfect contact. If you're going to steal ideas, steal them from the best....

I’ve seen those wedge bridges in photos, but not with sufficient detail to try to copy one. Is there a tut or measured drawing floating out there in the webosphere?

I suddenly have a lot of time right now to experiment.


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Yes in my opinion the Hauser method and most all methods of having an adjustable neck angle decouple the neck and body at least to some degree and that's potentially problematic to some when it comes to tone.

Do you remember the heresy.... and how Bob Taylor was nearly excommunicated from the guitar world because he had the unmitigated gaul to engineer and produce a guitar with a bolt on neck and an acoustic guitar to boot? For years the argument of tonal loss raged on with factions drawn and divisions enduring to this very day.

Now I'm not that extreme with my views mind you and Bob Taylor did a wonderful thing in my view. But the Hausers that I've had the opportunity to spend time with, there have been three so far do sound thin to me compared to similar vintage Martins with a fixed, dovetail neck joint.

But that aside I don't really see the value of an adjustable neck joint on an arch top anyway. One of our professional clients who is well known uses 14 - 75 strings on his arch tops and he tends to like old Epiphone New York and g*bsons. His guitars may need neck resets in time because of all the string tension and it's not that uncommon for an arch top to eventually need a neck reset.

But on the other hand the D'Aquistos that we take care of for a client who often backed up Joe Pass back in the day and that were built by D'Aquisto for our client show zero signs of needing neck resets and it's been many decades for these old girls.

Instead the adjustable on the fly bridge is taking care of any seasonal rises and falls in the top and I know at least three arch top players who play out and will adjust the thumb wheels on the fly on stage if they wish to and I've seen them do it too.

I don’t know I of too many musicians adjusting their guitar action during a show, but if that’s a thing, then perhaps the adjustable bridge is a must. Though, keep in mind, in addition to requiring the foot to be perfectly seated on the body, the bridge has to be perfectly seated on the wheels. So unless the adjustment is made equally on both the treble and bass sides, the bridge will be skewed and contact with the wheels will partial. It may not make a huge difference. On the other hand, as I said, the fixed bridge I made, substantially improved both the volume and tone.

Yep g*bson used to use a fixed bridge on some of their lower price mandos and this likely improved volume on the less resonant bodies by taking all that hardware store metal out of the mix.

But I would suggest that we human bags of mostly water (Star Trek reference..) have difficulty discerning tonal improvements from volume increases. I know that I do, my Bassman sounds better louder but it's actually only louder and the tone produced is likely not much different if different at all.

I'm a former builder who built over 50 guitars and people liked my stuff a great deal. I was fortunate enough to have been here on this forum when we had some Lutherie pros here who shared what they knew selfishly, Rick Turner and Mario P. They both got eventually pissed at the BS here and left so some of you folks don't have the benefit of their contributions. Why this matters is this:

Rick and perhaps Mario too would be quick to point out that your fixed bridge is not very serviceable. If the action needs to come down sure we can slot the string slots deeper and make the adjustment that way. But when it's February and it's difficult to keep the house or venue at even 40% RH that top dome shrinks and the action comes down. How do we now raise action?

That's my point "serviceability" and that ability to be adjusted even if on the fly during a performance is important to arch tops and in my world no self respecting pro player would ever play a guitar that cannot be easily adjusted when need be especially.... on the road.

I think that you are right that the volume improvements are noticeable but the trade off is serviceability that that is a trade that I would not be willing to make.

Yeh , I understand completely. I had to raise the bridge twice on my archtop over this winter as well as redress the fret ends. I’m sure when we turn the heating off, I’ll have to lower the bridge again. It’s just the nature of archtops. That was why I was contemplating the adjustable neck. Well, thanks for the advice. I may be something I try in the future.