• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

Double Bass Diagonal Back Brace on Upright Bass

A

amuri

Nov 28, 2010
2
0
Boston
#1
Hey all!

I recently had a pretty major overhaul on my upright, I had the back bars removed and a single diagonal brace installed. This was all done at Boston Bass Works, by master luthier Michael Hartery.

Ive had a lot of work done by Michael, all contributing to furthering the quality of my upright. This back brace really did wonders! It's opened up the sound by letting the bass work with its self, and not fight against dead spots that kill vibration and frequencies. Its a wonder to play, I can feel ever note ring through my bass clearer than ever. It lightened it up a little too, which let it project more and be more precise in its attacks.

The picture should show what the final result was. His work is flawless! Any one in the boston area, or around that needs work should seriously stop in and have a chat with Michael.

http://www.flickr.com/photos/56467664@N04/5217180478/

Let me know what you think! And if your interested in this procedure, definitely check out Boston Bass Works!
 
#3
For some time, Eric Roy over at Upton has been using a "propeller wing" diagonal brace on the Karr models. In his case, the brace was developed in collaboration with Jim Hamm, Karr's luthier.
 
#4
amuri said:
Hey all!

I recently had a pretty major overhaul on my upright, I had the back bars removed and a single diagonal brace installed. This was all done at Boston Bass Works, by master luthier Michael Hartery.

Ive had a lot of work done by Michael, all contributing to furthering the quality of my upright. This back brace really did wonders! It's opened up the sound by letting the bass work with its self, and not fight against dead spots that kill vibration and frequencies. Its a wonder to play, I can feel ever note ring through my bass clearer than ever. It lightened it up a little too, which let it project more and be more precise in its attacks.

The picture should show what the final result was. His work is flawless! Any one in the boston area, or around that needs work should seriously stop in and have a chat with Michael.

http://www.flickr.com/photos/56467664@N04/5217180478/

Let me know what you think! And if your interested in this procedure, definitely check out Boston Bass Works!
Click to expand...

How big were the original braces? Just looking at the photo, and the brighter areas where the old braces used to be, it doesn't seem like the new diagonal brace would have made things too much lighter (physically) unless those old braces were really high. But of course you know the best since one can't always tell from pictures alone.

I was considering doing this on my bass as well (plywood flat back, carved top), but my current braces are quite thin already and it doesn't look like the diagonal brace of this size would reduce any weight in my case.

George
 
#5
George700DL said:
How big were the original braces? Just looking at the photo, and the brighter areas where the old braces used to be, it doesn't seem like the new diagonal brace would have made things too much lighter (physically) unless those old braces were really high. But of course you know the best since one can't always tell from pictures alone.

I was considering doing this on my bass as well (plywood flat back, carved top), but my current braces are quite thin already and it doesn't look like the diagonal brace of this size would reduce any weight in my case.

George
Click to expand...

The original braces were really blocky, and very thick (and poorly glued on with carpenters glue!). There were 3 original braces, all going horizontal. The new brace is rather thin, and its width lets the soundpost have more room for movement incase you want to experiment with placement.

One of the biggest reasons it helped with the sound so much is because its running almost completely with the grain, so doesn't act as a mute, and more as a continuation for the sound to travel. In the end it probably weighs not too much less than the old bracing, but the orientation adds so much to the sound that it would out weigh any weight gain issues.

~Alex
 
#6
amuri said:
The original braces were really blocky, and very thick (and poorly glued on with carpenters glue!). There were 3 original braces, all going horizontal. The new brace is rather thin, and its width lets the soundpost have more room for movement incase you want to experiment with placement.

One of the biggest reasons it helped with the sound so much is because its running almost completely with the grain, so doesn't act as a mute, and more as a continuation for the sound to travel. In the end it probably weighs not too much less than the old bracing, but the orientation adds so much to the sound that it would out weigh any weight gain issues.

~Alex
Click to expand...

That all makes sense, thanks.
 
#7
Jim Hamm discussed this at the VSA bass luthier week at Oberlin this summer. He creates a circular area in the diagonal brace under the soundpost. His main reason for using a diagonal brace was to minimize cracks due to the difference of shrinkage between spruce and maple. He pointed out that this is how acoustic guitars are braced. It makes sense that it also allows the back to vibrate more freely.

Jack Hill
 
#8
bassrome said:
Jim Hamm discussed this at the VSA bass luthier week at Oberlin this summer. He creates a circular area in the diagonal brace under the soundpost. His main reason for using a diagonal brace was to minimize cracks due to the difference of shrinkage between spruce and maple. He pointed out that this is how acoustic guitars are braced. It makes sense that it also allows the back to vibrate more freely.

Jack Hill
Click to expand...

I know this thread is being dead forever... I like the idea of a Diagonal Brace, but what do you mean by: "He creates a circular area in the diagonal brace under the soundpost"
 
#9
I repaired a Flatback a couple of years ago. I converted the back to diagonal bracing. When I was working on it I consulted Mr. Ham about the details. Here is his response to a question about the disc:

"The brace is spruce, the disk is maple 1mm thick, I also recommend a 1mm thick veneer where the soundpost hits the top. "
----Jim Ham

ImageUploadedByTalkBass1385501885.556494.jpg

The bass I worked on was pulled from the grave so I can't say how it changed the sound but it had a beautiful sustain after I was finished.
 
#10
bassrome said:
He pointed out that this is how acoustic guitars are braced.
Click to expand...

That's not really true. Its how most steel string guitar TOPS are braced - the backs are almost always ladder braced in a pattern similar to a Saxon flat back, though the brace shapes are quite different.

The higher arch and much narrower width of a Martin-style back brace would do a better job of stiffening a flat bass back without adding unnecessary mass. Add a sound post platform and you're all set. ;)
 

Latest posts

Top Bottom
Back