Double Bass Carbon fibre bridge...?

[swingingoodtime]

So, other than being a TOTAL b*tch to work, what do people think about the concept of a carbon fibre bridge...?

(Just musing. Not really considering it. Well, not much, at any rate...!)

 

[powerbass]

Moses Graphite used to make one, personally I don't see the point unless you want to tinker.

 

[Jake deVilliers]

The material is far too stiff. The reason we thin bass bridges as far as is practicable is to make them flexible enough to sound good.

Nothing deader sounding than a big, fat bridge...

 

[Philonius]

I know approximately zero about DB bridges, but hey, this is the internet! Carbon Fiber can be made into nearly any shape; strand orientation, density and stiffness are all variable. I'd think you could make a bridge as stiff or flexible as you'd want.

All it takes is $$$$$$.

 

[MostroDB]

I suspect it sounds very shrill, particularly arco.

 

[Phil Rowan]

I also suspect there's a good reason bridges are made of what they've been made of for a minute or two.

 

[swingingoodtime]

The material is far too stiff. The reason we thin bass bridges as far as is practicable is to make them flexible enough to sound good.

Nothing deader sounding than a big, fat bridge...

Hi Jake,

Thanks for that! I'm fascinated; I thought that the function of the bridge was to form as stiff & efficient a coupling between the strings and the top. As such, I would have thought that flex was bad. I also thought that the thinness was to decrease surface area contact with the strings to reduce friction and increase contact pressure (improving the efficiency of the coupling).

I totally defer to your considerable expertise and humbly have some questions, please:
- How much does the bridge contribute to tone compared to the top?
- What function does bridge flex play in the energy transfer?
- Given the direction that the strings vibrate, and the direction that I'm assuming the bridge flexes (perpendicular to the faces), aren't these at right angles to each other? How do they then interact?

Re weight, CF offers high strength to weight, so I was thinking you'd be able to maintain a low mass/high thinness bridge, but if flex (or lack of) is an issue, then I guess it's not such a good choice overall.

I suspect it sounds very shrill, particularly arco.

I suspect you may be right; very stiff material will transfer high frequency energy well, although it'd be interesting to see what impact it also has on the rest of the frequency spectrum too. Perhaps 'clinical' & 'precise' may be the result as opposed to 'warm' & 'colourful'. (Maybe that's what Jake meant by 'dead' sounding; perhaps flex results in extra harmonics that warm up the sound).

I also suspect there's a good reason bridges are made of what they've been made of for a minute or two.

I agree, although I'd venture that it's more to do with material availability, technology, cost and time/effort to work the material than purely tradition. Who's to say there's not a man-material out there somewhere (now or in the future) that may actually be as good as or even better than current-day materials?

Thanks for the input! Looking forward to your answers and other thoughts...

 

[Emanuel Apascaritei]

Hi,

I know we´re talking about DB bridge here but I´ll share my point of view.

I did carbon fiber spacers to obtain 18 mm string spacing on my bass. First I tried with metal spacers but had unpleased overtones. Then when I tried the carbon fiber all that overtones where gone and had nothing but good tone full of harmonics.

The function of the bridge is to transmit the vibration direct to the body. The carbon fiber does that very good so I see no reason why not try it on a DB.

Back in the old times the luthiers didn´t know of the existience of the carbon fiber, so the wood was the best choise. It may still be, but try diferent things leads us to evolution.

Just my opinion.

 

[robobass]

I bet a CF bridge could be designed which had all the properties of a good wood bridge and possibly was even better in some respects. Look at the success of CF bows. But the expense of developing such a thing seems to make the idea impractical, not to mention resistance from luthiers who would have to fit the thing. Also, wood bridges can be tweaked (thinning, enlarging the holes, etc.) in the shop to optimize them for the bass being fitted. A CF bridge could not.

 

[swingingoodtime]

I bet a CF bridge could be designed which had all the properties of a good wood bridge and possibly was even better in some respects. Look at the success of CF bows. But the expense of developing such a thing seems to make the idea impractical, not to mention resistance from luthiers who would have to fit the thing. Also, wood bridges can be tweaked (thinning, enlarging the holes, etc.) in the shop to optimize them for the bass being fitted. A CF bridge could not.

Oh yeah. My experiments with a CF soundpost were interesting, but working it was tough; even just trimming the chamfers on the ends was a LOT of work...

 

[MostlyBass]

Have you considered contacting Invalid Link Removed

They've been making carbon fibre / composite instruments for years. Not sure about the bridges but their experience and knowledge may be a great starting point.

 

[swingingoodtime]

Have you considered contacting Invalid Link Removed

They've been making carbon fibre / composite instruments for years. Not sure about the bridges but their experience and knowledge may be a great starting point.

Cool, thanks for that; their CF bass looks very interesting too (not to mention expensive!). Ironically enough, they use a wooden bridge...

I'll drop them an email & see what they say.

 

[Andrew McGregor]

Cool, thanks for that; their CF bass looks very interesting too (not to mention expensive!). Ironically enough, they use a wooden bridge...

I'll drop them an email & see what they say.

They don't sound that great or play particularly well; sounds way too hollow and boomy. Something not quite right with the design.

Not saying CF is a bad idea, just that particular implementation doesn't work.

 

[Damon Rondeau]

There's an animation out there somewhere -- can't be bothered to find it; I probably saw it 10 years ago whilst going through Bob Gollihur's bass links page -- showing the motion of a bass top and bridge in action. There is a lot more flexing and movement going on than you would imagine without empirical observation. You can see how the bridge, the soundpost and the bass bar work together -- the bridge pumps that bass bar like crazy.

The quarter-sawn maple that good bridges are made of is an amazing, high-quality natural material. People can experiment all they want and that's a good thing, but the idea that there's some kind of flaw with wooden bridges that carbon fibre can improve? I doubt it.

 

[MostlyBass]

Yup - it's amazing how much things move... BUt they have to - otherwise there wouldn't be any sound.

There's an animation out there somewhere -- can't be bothered to find it; I probably saw it 10 years ago whilst going through Bob Gollihur's bass links page -- showing the motion of a bass top and bridge in action. There is a lot more flexing and movement going on than you would imagine without empirical observation. You can see how the bridge, the soundpost and the bass bar work together -- the bridge pumps that bass bar like crazy.

The quarter-sawn maple that good bridges are made of is an amazing, high-quality natural material. People can experiment all they want and that's a good thing, but the idea that there's some kind of flaw with wooden bridges that carbon fibre can improve? I doubt it.

 

[swingingoodtime]

There's an animation out there somewhere -- can't be bothered to find it; I probably saw it 10 years ago whilst going through Bob Gollihur's bass links page -- showing the motion of a bass top and bridge in action. There is a lot more flexing and movement going on than you would imagine without empirical observation. You can see how the bridge, the soundpost and the bass bar work together -- the bridge pumps that bass bar like crazy.

The quarter-sawn maple that good bridges are made of is an amazing, high-quality natural material. People can experiment all they want and that's a good thing, but the idea that there's some kind of flaw with wooden bridges that carbon fibre can improve? I doubt it.

That'd be great to find; I'll do some digging as I'd love to see it. I don't doubt that the bridge itself flexes, but I'm still intrigued as to how this affects the tone.

I'm certainly not suggesting that wood is flawed and unsuitable (and that CF is in turn otherwise), but at the same time, we also praise the virtues of close-grained quarter-sawn maple over lesser quality wood, so there would already appear to be some substance to the notion that a greater density or stiffness to weight ratio is better. Would CF be stiffer than wood? Almost certainly. Lighter? Maybe, or close. Does that automatically make it 'better' (that in itself being a vague & subjective measurement)? Maybe, but not necessarily; other than the issues of working with the material already mentioned, it could be a bridge too far (hah! No pun intended!) in that it loses something along the way (as I mentioned before, maybe too clinical? Kind of reminds me of the 'clinical' digital vs 'warm' analog debate in hifi circles...).

Alternatively, it could just be that because we've gotten so good at using it (having done so for so long) that we perceive no further need to improve and may be (that's may be) missing out on something better. Having said that, in line with the law of diminishing returns it could be only 0.000001% better, so may not be worth it overall when you take all the factors into account.

Yup - it's amazing how much things move... BUt they have to - otherwise there wouldn't be any sound.

Agree. But I still don't get how flex in the bridge helps; the apparent lack of directional interaction of flexing between bridge vs strings/top not withstanding, it would be like having engine piston rods made of rubber; some efficiency would be lost between the piston head and the wheels...

Thanks for all your input, everyone; please keep the thoughts coming! This is what I love about TalkBass; it's such a great environment to explore concepts, opinions, & experiences (with a huge hat-tip to you experts/professionals out there)...

 

[swingingoodtime]

Back in the old times the luthiers didn´t know of the existience of the carbon fiber, so the wood was the best choise. It may still be, but try diferent things leads us to evolution.

Absolutely. Even if it tells us: "Well, that was dumb. Don't try that again!"

 

[Damon Rondeau]

There is also the practical side to consider: every bridge needs to be custom-fit to the instrument. Wood -- especially the quarter-sawn, carefully selected and aged Carpathian maple used in good bridges, which shapes and cuts almost like stone in some ways -- is ideal for this.

That's about all I've got to say on this subject. I just wanted to throw in my two bits in defence of wood. I'm not against carbon fibre or experimentation or blue-sky what-iffing -- far from it. I just think carbon fibre's going to have to bring a lot to the game if it wants to take down the champ. Champ's worn the crown for a loooong time.

 

[swingingoodtime]

There is also the practical side to consider: every bridge needs to be custom-fit to the instrument. Wood -- especially quarter-sawn, carefully selected and aged Carpathian bridge maple, which shapes and cuts almost like stone in some ways -- is ideal for this.

That's about all I've got to say on this subject. I just wanted to throw in my two bits in defence of wood. I'm not against carbon fibre or experimentation or blue-sky what-iffing -- far from it. I just think carbon fibre's going to have to bring a lot to the game if it wants to take down the champ. Champ's worn the crown for a loooong time.

Absolutely agree with both of your points and I very much appreciate your input; I am just blue-skying more than anything and certainly aren't thinking my 2-tree Despiau was a waste of money. It's just that the tinkerer-part of my brain constantly toys around with 'what if?' scenarios. Fortunately, the rational part usually (but not always!) pours cold water over it with practicalities & sensibilities. (I can't even start to conceive how difficult shaping the bridge feet would be!)

 

[Damon Rondeau]

As for shaping the feet: what about a kind of plastic? Get it warm enough to be malleable. Press it against the top plate. Done. If there was no impact at all on tone (and I make no claim one way or t'other there), and assuming there's no philosophical/aesthetic/pseudo-religious objection, it's a straight-up economic decision.