Question to Oud Makers only

Hello oud masters,

My question is ...

Can Floating Bridge Oud be converted to normal Bridge oud?


Thank you

Normal bridge

RE: Your Participation

Your Ideas

Hi Elie

Very nice of you that you cared about this problem of mine. Man, it is annoying that I can not use the strings I bought a while ago because they are short for the floating bridge style.

I find the second idea is more reasonable. It will still make the oud look good and will do the trick. Actually I can make the extension plate my self. I can make it out of reasonably thin brass to give it that old look. I will let you know about it when I do it.

Thanks Elie.

Stay well

OK Mr. Science, - while the physics of the vibration moments may lead you to believe the fixed bridge requires greater structural integrity, there are some fatctors you need to factor in:
1. The floating bridge is usually tuned higher or with heavier strings to produce the same or greater volume than a fixed bridge. This induces a relatively higher load downward than the fixed bridge's torque load.
2. The fixed bridge's torque moment is offset somewhat by the tension component through the soundboard itself, resisted by the tail block. The forces at the bridge arwa are therefore mitigated to the rockin' (and rollin') in the imediate area of the face, which requires lighter bracing and edge support to produce the same volume as would the floating bridge.
3. Historical evidence of conversions and uninformed builds of floating bridge ouds have often resulted in a collapse of the face under the floating bridge.
4. The structural details of the original (and successful) Bashir design executed by Mohamed Fadel Hussein show a more robust structure - a thicker soundboard, heavier braces and additional edge supports (corner blocking).
-just a bit of empirical evidence to ground your theory...

Quote:

Originally posted by Dr. Oud OK Mr. Science, - while the physics of the vibration moments may lead you to believe the fixed bridge requires greater structural integrity, there are some fatctors you need to factor in: 1. The floating bridge is usually tuned higher or with heavier strings to produce the same or greater volume than a fixed bridge. This induces a relatively higher load downward than the fixed bridge's torque load. 2. The fixed bridge's torque moment is offset somewhat by the tension component through the soundboard itself, resisted by the tail block. The forces at the bridge arwa are therefore mitigated to the rockin' (and rollin') in the imediate area of the face, which requires lighter bracing and edge support to produce the same volume as would the floating bridge. 3. Historical evidence of conversions and uninformed builds of floating bridge ouds have often resulted in a collapse of the face under the floating bridge. 4. The structural details of the original (and successful) Bashir design executed by Mohamed Fadel Hussein show a more robust structure - a thicker soundboard, heavier braces and additional edge supports (corner blocking). -just a bit of empirical evidence to ground your theory...

The expaning waist is an interesting thought, especially as I am experiencing the same phenomenon myself. Perhaps my own bridge should be converted to fixed? The corner blocks would certainly help avoid the side poping out, but I have not heard of that type of failure. I know that some floaters simply deepress the face until it's unplayable or collapse completely into the bowel. The fixed bridge also pulls at the tail, but through the soundboard itself. I think the force is very similar at the end of the bowel, but very different in the bridge area.
As for the banjo - the dynamics of a skin membrane vs a thin wooden plate don't seem to be very similar to me, but maybe my layman's brain just can't grasp the concept. Perhaps you could enlighten us in that area, professor?

I found a picture of when I did this conversion from fixed to floating brige oud. I was verry worried about that phenomenon and although Iam not a physics major or a wood worker by any means I came up with a way of stoping the downward pressure from the floating brige. I used Jameel's (TM) lap sanding technique to fit them and I clamped them to each side under the braces so that it barely rests on them. So far my oud hasnt collapsed.
The down sides I have experianced doing this conversion is that for some odd reason the action is really high now. Either the neck shifted when I took the face off? or Iam using to high a brige for a floating brige oud. Another thing is that the sound is extremely bright in the nylon strings and absolutely dead in the wound strings. The wound strings now sound more like a guitar would sound like. I can blame the fact that I resused the same face to do the oud which was bad quality to start with. My workmanship isnt the greatest concidering all I had was a saw and carpenter's glue so I was restricted in that sence.

I wonder tho if using such stopers for the brace was a bad idea sound wise? is it stoping the brace from vibrating?


Now I dont know really what the effect on the sound was from this

Samir,
It sounds like the sound board isn't doing its job and you are mainly getting the vibrations from strings. This could happen if the bridge is on a brace or too close to one. Or maybe there isn't enough tension in the strings to supply the downward force, like the good Doc mentioned, floaters end up needing more string tension.

Well Doc (I know it is a deep subject, the well that is) it was just a thought about the banjo. I also heard of new acoustic guitars having only one brace!
Could it be as the strings of the floater pull the edge of the bottom towards the neck which in turn pushes that end of the sound board along with it creating a crate around the bridge. While the fixed bridge will also pull the board towards the neck but it pulls upwards also raising the action over time as this happens and the oud is not completely dead in this case? Just some thoughts!

Regarding the busting at the sides for us humans seems to work the other way -- when we bust out, its all around especially at this time of the year with all the festivity foods and desserts.

I am hesitant to express a point of view in this thread, because:
1/ I am not an oudmaker
2/ I lack the scientific knowledge of the other posters

But here's my .02c worth.
I do not think one should generalise that ALL floating bridge ouds have thicker sound boards, that ALL floating bridge ouds need heavier gauge strings to perform optimally and that ALL makers use similar bracing patterns in their floating bridge ouds.

I base this on the fact that I have tried a few different gauges of strings on my Bashir style oud by Nazih Ghadban.

The heaviest of these (and therefore the best if higher tension is the measure) was a set of Aquila Nylgut Arabic strings. At first I liked them, but I soon realised they did not sound as good (on that instrument) as the lower tension Pyramid lute strings that were fitted previously. I have now fitted a super light set of Pyramid lute strings. I had to use a slightly higher bridge to avoid buzz, but the sound, whilst not quite as loud, is excellent. The lower tension also allows me to play faster and cleaner.

The vibrating stringlength is 60 cm. For those interested, here are the gauges and tensions:

cc .650 mm = 3.3 kg - (PVF unwound) 32.36 Newton

All other strings are Silver- plated wire wound on special
multifilaments with high tensile strength and low tension.

gg .906 mm = 3.4 kg 33.34 Newton
DD 1.010 mm = 3.4 kg 33.34 Newton
AA 1.017 mm = 3.6 kg 35.30 Newton
FF 1.025 mm = 3.6 kg 35.30 Newton
C 1.237mm = 3.6 kg 35.30 Newton

I don't know a thing about torque and AFAIK the only thing that rocks backward and forwards is the guy playing it, but I know what I like

Regards,

Greg