Pliage

Bohemian · July 2014

Pliage or bent top..

What does it add, structurally or tonally ?
Given two otherwise exact builds.. let's say by Dupont as an example.

Any observations or comments welcomed.

Bob Holo · July 2014

It's not precisely that way. I know you'll hear a lot about how it imparts some particular characteristic, but that's not true. Sometimes people will say it gives a guitar more 'snap'. If you have to describe a pliage in 10 words or less, that's probably the best answer.

So... what is the pliage? (verbose answer) If it's done correctly, it is a strength element that allows you to make the area under the bridge relatively strong without adding mass or tying it to other areas forward or backward of the bridge. Because it adds strength without mass, it can help the guitar be more efficient. But if the guitar is not tuned with it in mind, it can ruin the guitar. Your question hits the issue right on the head. I think the confusion over the pliage is precisely because it is viewed as a feature to be added or not. I think part of the confusion is precisely because the pliage is often just "added" by luthiers because it's considered to be difficult to do. The results are not consistent because sometimes pliages are not done properly or are added to a guitar that was designed to function without it. Ironically I've seen some guitars with "added" pliages that were good precisely because they weren't affected much by the pliage because the pliage was done in a way that rendered it relatively inert. I saw one guitar that was pliaged right over a brace. Sort of defeats the point of having a zero-mass brace if you attach it to a brace. lol. But hey, in one way it worked I suppose, in that it allowed a pliage to be there without messing up the sound of the guitar. That was the most egregious one, but I've seen a few head scratchers. Anyway, it's one of several ways to increase strength without adding mass. It works well in conjunction with moustaches, but some of the old Italian builders didn't use either and made amazing guitars - using different techniques to achieve similar outcomes.

Some of the things you can get with extra efficiency and lightness of soundboard depending on how you choose to deploy it include:

Big comfortable bass with some transparency and grace to it - like the early Selmers

Really articulate, midranges that break up sweetly and get grungy when played loud without losing too much of their warmth - like the mid period Selmers

Very refined muscular midranges and trebles that retain their clarity and don't get overly dark or restrained like many guitars that are built with higher mass and more arching for greater control & focus.

But it's not the only way to get the job done. It's a good way though.

Bohemian · July 2014

Thanks Bob...

Jim Kaznosky · July 2014

@Bob Holo - Thank you for this excellent answer. You mentioned tuning the top. I'm curious as to what this means, how it is accomplished, and to what standard is a top tuned. I'm not a luthier, but I am interested in understanding what goes behind making the unique sound of these guitars.

Jazzaferri · July 2014

Thanks @Bob Holo for the insightful reply. As I have said a few times before building guitars is still an art, yes there is a lot of technical knowledge and for the best builders, scientific study of the processes and the attributes, in the end, the luthiers idea of what he wants to achieve, how he wants it to sound will be made in his head and heart.

:laugh: I have yet to have a serious session on a Holo but my ears tell me Bob is truly an artist of the first water.

Bob Holo · July 2014

There are a lot of books on top tuning. Romantic guitars, lutes and mandolins are probably the closest analogs to GJ guitars. There are many known techniques. The thing is, I've studied great guitars with huge variances in every metric and come to the conclusion that there were a lot of flaws in those methodologies and a lot of different ways to build a great guitar. Don't get me wrong, I'm glad I learned them and built jigs to do them and used them because it helped me get an objective sense of what was happening and it forced me to think through every aspect and separate fact from myth and define inter-relationships between variables. I still measure things to have a consistent starting point, and I take reality-check measurements from time to time to make sure I'm not straying or skewing over time (or if I am, whether it's a good thing) and I document what I've learned from each guitar to a set of measurements I'd never share with anybody much less put on the internet for every knockoff guitar company in the world to download. But my eyes, ears & fingers seem to be fairly consistent provided the temperature and humidity are constant and I'm well rested. The human body is amazing. How does a basketball or soccer player adjust all those variables instinctively while flying through the air sideways and make a difficult shot past two defenders... Several years ago I started building a branching logic structure of how to tune tops and realized it was either going to become arbitrarily huge or I needed another way to think about it. I reached out to a couple of gentlemen who have been building guitars at a very high level for decades. One classical, one flat-top and one lute/romantic maker. All three said they did basically the same thing. They measured and quantified till they realized that all they were really doing was calibrating themselves. The bottom line is that if you want a guitar to turn out well, you have to understand how the variables interact and roughly which ranges each has so that you're not pushing one too far and impacting others. Then the truth of it is, you start by bringing the soundboard down to whatever your own personal starting point is and spend some time with it and ask the question: "OK, what does this specific soundboard want to be and how do I get it there and which design most closely matches that and what density of bracewood will it require and etc...". Then you work toward that goal and observe how closely the soundboard is tracking - and if it isn't - you need to have the humility and common sense to stop and re-assess and in some cases, to make firewood. ;-)

Also, no two guitars are alike and what one person likes often another doesn't. I took two Selmer models to a festival recently - one mid period and one late period inspired - and asked artists for feedback. The feedback on the characteristics of each guitar was fairly consistent, but some strongly preferred one and some strongly preferred the other, and some identified the differences but had no preference, saying that they were simply different tools.

OK... time to go work.