Double Bass Theory on Top Construction

[turf3]

Many years ago I read a book about violin/family construction, in which the author theorized on an "improved" method of top construction (in basses, this would only apply to carved tops).

The theory was that in the standard carved top, because it's arched as you go from north to south (in the direction the strings run), that the grain structure of the wood naturally runs out on the sides of the arch. In other words, the little tubes of which wood is made up, don't run clear from the neck joint all the way down to the tailpiece saddle; they can't because the wood is carved away to make the top arched in that direction (and of course it's arched in the cross-grain direction, too).

So the proposal was to make a top where the center section, between the F holes, would be one continuous strip of wood, formed into the longitudinal arch of the top; and then laminated to a left side and a right side which would be carved as normal (because they're interrupted by the F holes and the center bouts, it wouldn't be meaningful to try to make them continuous in the way of the center strip).

My question is, does anyone know if such a construction has actually been tried, and if so were there any conclusions?

 

[bassmanbrent]

This is only sort of on topic, but here goes... There was a company, who's name I forget at the moment, that was making basses with solid tops that were pressed. In other words, they took a flat piece of solid wood and pressed the arch into it with pressure and probably steam. Just like a Kay top, only not plywood. I think some of them sounded good, but they had lots of structural issues as the tops tried to return to their former shape. Maybe someone else around here knows what I'm referring to and can chime in...

 

[carl h.]

I don't recall the name either, but I have heard of those pressed tops not doing well. I always viewed those as a budget attempt at a solid top, not something innovative. I don't know what advantage not carving a solid top would give but graduation would be impossible and compressing seems like a bad idea too.

 

[1st Bass]

Weren't some of the Viols and Gambas built with multiple-stave tops, much as is described, here? It makes sense from the perspective of wood use, as well as possible tonal advantages. I have no idea whether it is a great idea or not, but it would certainly make bass top wood more obtainable. The little bass I just completed is less than 27" wide in the lower bouts, but that still meant buying spruce that was very thick at the center-join, to achieve the arching, and at least 14" wide to accommodate the width...(and, actually it was a good deal wider.)

So, if I had bent a stave that took up the entire center, say, 8" wide, and joined it to side staves, then assumedly the side sections would only have to be 10" wide, and only about 1-1/2" thick on the inboard edge, as opposed to the 2-1/2" x 14" minimum required for a two-piece book-matched top.

I'm not really sure whether the idea has any merit in terms of sound, but I can see it might be practical in regard to wood use.

 

[turf3]

I think (but it's not here with me so I can't say for sure) that my bass top is made up of 4 pieces - but still carved in the normal way and with a centerline joint. I know the back (flat) is either 4 or 6 pieces.

 

[bassmanbrent]

I always viewed those as a budget attempt at a solid top, not something innovative.

You're absolutely right. It was an attempt to make a solid top bass that was almost as cheap as a plywood one.

 

[GretschWretch]

There was an article I read years ago in an issue of the journal Early Music that was about older (pre-modern) and smaller bowed strings. Some had had their tops removed and it was noticed that as the wood grain approached the endblocks it tended to converge (i.e. get closer together). The conclusion was that these tops had been both carved and bent.

 

[Eric Rene Roy]

Bill Fulton (violinmaker) was a big proponent of pressed tops of violins, and it would get heated at VSA conventions back in the 90's. Search Bills name on Google and I'm sure there are articles about what he was doing.

My only experience with tops I knew was pressed were these crappy cellos from Sri Lanka I used to setup for an importer near Boston when I was in violinmaking school. They were horrid.

 

[robobass]

A fellow student at Mannes had one of those pressed top basses. It had a better upper register than a plywood, but not much low end, and kind of felt generally more like a plywood than a carved top. As bending the center section and attaching unbent "wings" to it? It just seems like the risk of it bending later would outweigh any potential benefit. The grain does run out, but pretty gradually. I'm not sure having it not do so would have any tonal effect.

 

[turf3]

A fellow student at Mannes had one of those pressed top basses. It had a better upper register than a plywood, but not much low end, and kind of felt generally more like a plywood than a carved top. As bending the center section and attaching unbent "wings" to it? It just seems like the risk of it bending later would outweigh any potential benefit. The grain does run out, but pretty gradually. I'm not sure having it not do so would have any tonal effect.

Well, it was just a theory. I was wondering whether anyone had actually built a violin family instrument according to the theory, and it sounds like if it has ever been done, it certainly didn't get any attention or reputation.