Bridges: do sharp vs rounded corners make any tone difference?

[Mark Marino]

I've noticed some higher end mandolins have rounded corners on the bridge- especially the top section of it. At first I assumed this was purely for comfort, but realizing how much difference the bridge can make in tone, I'm now wondering if tone might be a factor as well. I've been thinking of rounding corners on my CA bridge but thought I'd seek advice before doing so. I assume sharp corners may act to radiate very high frequencies? Or is the effect so small there'd be no appreciable difference?

[Bertram Henze]

The bridge does not radiate sound - the top does.

[colorado_al]

It doesn't make a difference in sound, as long as you don't make changes to the height or location where the strings touch, or to the size and fit of the bridge feet. The rounded corners are really just a sign that someone spent that extra 5 minutes sanding it for comfort. For me, that is one of the first things I do when I get a new mandolin or new bridge. When I play, I rest my wrist on the strings behind the bridge and a rounded saddle is much more comfortable. The amount of wood removed is very little, and I have not noticed any change in sound quality.

[Marty Jacobson]

It's easier to make bridges with sharp corners... you just run it through the shaper, and it's done. Slightly rounded corners indicates that it's been sanded. Either can look nice if it's well done.

[pit lenz]

Very interesting topic!
I hope that Stephen Perry will chime in. His mandolin fine tuning process called "acoustic blueprinting" seems to deal with that, too. see here (http://mandovoodoo.com/mandolin2.html)
I'm really looking forward to his take on that and a respectful conversation...:)

[GTison]

I believe in bridge modifications. I like the rounded corners on my bridge. If nothing else it adds to comfort for me as I hate feeling sharp corners against my hand.
Now, violin bridges have a lot of shaping. That must affect sound a bit. And in my mandolins changing the saddle seems to make sonic differences. Red Henry's experimental bridges, and other things indicate bridge mass changes tone. So, there may be advantages in sound to certain shaping actions, in certain mandolins.

[sunburst]

Bridge mass affects sound, but frankly, it takes quite a bit of mass difference to make any sound difference. Rounding corners and polishing removes an almost imperceptible amount of mass from the bridge, and thus cannot be expected to make any perceptible sound difference.
I like for bridges to be smoothed, corners softened, and finished to some degree, whether that is fully polished or just fully sanded to some consistent surface condition. I don't know when the tradition of mandolin bridges being used straight from the machining operation started, but IMO it does not need to be followed, so I like to smooth and polish mandolin bridges. I cannot claim any improvement in sound from doing it, just a better appearance and feel (IMO).
As for violin bridges, comparing them to mandolin bridges is a bit of "apples and oranges". The tall, thin, light violin bridge behaves quite a bit differently from the short, thick, heavy mandolin bridge when the instrument is played. Assuming that the carving and "tuning" that goes on with violin bridges is applicable to mandolin bridges may not be a correct assumption, and personally, I don't believe it is.

[Larry Simonson]

I have wondered about the rounding of the inboard bridge and nut slot corners affecting intonation and or buzzing.