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What's the ideal weight for a steal string acoustic bridge? Light? Heavy?

Couldn't tell what's ideal but I have used bridges ranging from 20 grams to 28 grams. I suppose that each can be ideal depending on how each works within its given system. I'm still collecting data and trying to correlate mass and tone.

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JJ
Napa, CA
http://www.DonohueGuitars.com

I don't think there is an ideal weight. There's too many other variables.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

What Woody said.

I obsessed over bridges when I was designing my own and there is a legendary thread somewhere in the archives here about why bridges are shaped as they are... But that aside in Somogyi's books he does indicate what he believes to be an ideal weight for a bridge and I can't remember if it is 32 or 36 grams.

Mind you Somogyi's comments are for building within the context of all else that he does or uses for his own "system." Good books though and highly recommended especially if you are the sort to think about optimizing mass, materials, rigidity of rims etc.

Some food for thought that I kept getting back to no matter where I tried to go when exploring bridges and bracing test top after test top was that it's just not the bridge but the bridge plate, pins, saddle etc and even of course the top that all interacts as it will to produce the results that we get. I always look at the bridge as one half of a hot dog bun with the plate being the other half, top the dog, and pins the condiments.... Are you hungry yet - I am.... specially after watching the Michigan game yesterday!!!

A related topic is bridge pins. More than once we have been visited by a new member who proudly claimed that his fossilized Mastiff poop bridge pins produced "better".... tone. Discussions ensued and at the end of the day Al C. would suggest something like it's the difference in mass from one pin material to another that <may> be responsible for the <differences> in tone that we perceive (and some call better or an improvement). This suggests to me that messing around with pins can be done on a finished guitar or mule if you will to see where this takes us.

Anyway I view bridge weight as not unlike the size and HP of an engine that is required to move a car. Bigger cars may need a bigger engine and conversely smaller cars can use smaller engines. OO sized guitars may be able to have thinner tops than say jumbos etc.

So the answer is that it depends.... on everything else.

'But, how many grams of mastic poop?'
he asked heavily.

Now we are going to have to get into Mastiff dietary habits, before deciding whether or not the poop in question will have the proper density and stiffness for bridge making.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Any more, or less, than 34.1532 grams and the guitar will be utter failure.

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John Mayes
http://www.mayesluthier.com

I bet the sound filled the room though.

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Build log

i think it is a good idea to weigh the bridge for your build log.
wish i'd weighed the last 2.

There are three things to think of with the bridge; mass, stiffness, and damping. Gee, that's all the ingredients of impedance!

All else equal, making the bridge heavier will make it harder to move, especially at high frequencies. The result is often heard as a 'bassier' sound, but it's more like a 'less treble' tone.

Again, all else equal, increasing the stiffness also makes it harder to move the top, but in this case there's more of an effect in the low range, so the sound tends to be 'brighter' or more 'treble' (in reality, less bass, of course).

Increasing the damping tends to cut everything down, but, again, probably more in the treble. That's the theory, anyway: I just don't hear as much difference between, say, Macassar bridges and Rosewood ones as some people do.

There's probably an 'ideal' bridge weight for each guitar, depending on all the usual variables, such as the top and back woods, how thick they are, what the bracing's like, the sound you want, whether Jupiter is in opposition (as it is now), the wholesale price of coffeee in Burundi, and so on: all the usual stuff. I tend to find that weights between about 28-32 grams work well for me on steel strings.

One of my students got a little carried away carving her bridge once, and it ended up at something like 22 grams, iirc. The guitar (a spruce/IRW OM) got strung up with no finish, and was too bright. We put a lump of poster adhesive inside (four or five grams, I think) and that cut it down enough to be usable. A couple of years later, with a baby in the house, she decided to have me varnish it for her. When I got it done I took out the added weight, as the extra mass and damping of the varnish on the top had cut the highs enough that it wasn't needed. Lotsa variables in this equation.