one piece back

[Devitt]

does a one piece back fundementally sound different than a two piece back....and what about structual integrity....
opinions

[sunburst]

This has come up before. I tried "searching" a couple of times, but I couldn't find any old threads.

A one piece back doesn't sound any different than a two piece back, assuming similar wood.

The only difference in structural integrity would be in the rare cases where a back seam fails in a two piece back. That doesn't happen very often if the glue joint is good, so I'd say there's a negligible difference in structural integrity.

[Devitt]

Thanks John .... just kind of wondered about the tone....I did'nt think it would be a big factor but was'nt sure.

[Willie]

I once read where Roger Siminoff said that the back and sides of an instrument account for less than 2% of the sound so if a one piece back was any different than a two piece it wouldn`t be much, assuming he is correct.....

[kww]

Roger Siminoff said that the back and sides of an instrument account for less than 2% of the sound

One of those reasons that I wonder why so many people are willing to spend so much money to avoid laminate sides and back on an instrument.

[Gail Hester]

Try removing the back and sides and see if you still get 98% of the sound. Seriously, I can't help but think this is a misquote. http://www.mandolincafe.net/iB_html/non-cgi/emoticons/coffee.gif

[ourgang]

Me too, Gail. It seems to me that every stick of wood in the mandolin vibrates at it's own frequency and all those frequencies put together give you your tone. If not, what's with the tone guards that make such a difference. Just hold the mandolin to your body and compare the tone and volume to when it is held away from you.

[sunburst]

I believe different makers use the back differently.
I feel like I'm getting more contribution to the sound from the backs of my mandolins as I learn more about how things work. I wouldn't try to quantify what percentage of sound comes from the back, and I'm pretty sure it varies from mandolin to mandolin, but regardless, I think the back behaves essentially the same whether one or two piece.

Also, the stiffness, and other characteristics of the rim do affect the sound, to some extent. How much? I don't know. I don't know how you would measure.

[Jerry Byers]

I had a discussion awhile back on this with someone, and they thought a 2-piece had a little more punch to it. Would the seam act as a stiffner? Is it possible that two quality pieces of wood are better than one piece with possible variations in density across a larger area?

[Bill Snyder]

Most people try to book match their two piece backs, so it starts out as one piece then it is sliced, opened up like the pages of a book and glued. Although there can be quite a bit of difference in pieces of wood from the same tree, I don't think this would lend itself to much variation in density.

[Jim Hilburn]

Roger Siminoff has said a lot of questionable things about mandolins.
I think the back is about 60% of the equation, but of course I have nothing but my own opinion to validate such a claim.

[ron d.]

I agree with Ourgang, I was surprised at how much the tone changed depending on how I held my mando, so much emphasis seems to be put on the top (type of wood, aged wood, etc.) Backs are more considered for looks it seems. I played an old beat up Montana era Flatiron A that didn't seem as sensitive to position as my Laura Ratcliff A (one piece back by the way), so it varies I guess.

[mandoman15]

I think that the simminoff quote (if it is a legitimate quote) was really meant to emphasize the sonic importance of the top wood, aka the soundboard, and the importance of using a good piece of spruce with even grain for even tone. sort of hyperbole.

[Bill Snyder]

and the importance of using a good piece of spruce with even grain for even tone. sort of hyperbole.
Mandoman15 see this thread (http://www.mandolincafe.net/cgi-bin/ikonboard.cgi?act=ST;f=7;t=16181;hl=wide+and+grain +and+loar) for a discussion on the importance of grain count and even grain.