Bridge foot "ticking" - What to do?

[bonaventura]

I fitted a new bridge in January. One reason for replacing the old one was that it emitted a faint, just barely audible "tiki-tiki-tiki" or "flitter-flatter" like sound from the NW corner (looking from the front) of the E side foot. At first I wasn't sure where this sound was coming from. I thought it was the bass bar. But it definitely isn't that. It occurs only on playing the open A string pizz (also occurs on arco but is not audible).

The new bridge now does this too, since late May as the weather began to warm up and humidity increased. Before that, I didn't notice it with the new bridge.

Has anyone ever had this kind of sound coming from the bridge foot? My only concern is that it would damage the bass, it isn't really that audible.

I think it's the top making a sound as it vibrates against the underside of the bridge foot. There is a tiny gap there, since I can just barely slide an edge of paper under it, usually for about 1 mm (but sometimes 2 or 3 mm, depending on the angle the bridge is standing at).

I must say the surface of the top under that foot has an irregularity, a worn spot, I think from using a Realist (which isn't on now), and it was impossible to fit the foot to match that spot exactly. While the fit of the bridge is I think pretty good, probably about 99% contact, there is that one tiny spot on the corner that curves away from the top (the top is of course curving downward away from the strings at that spot).

I'd be grateful for any comments of any TB-ers who've heard this sound or even successfully corrected it, and of course from the luthiers out there if you would be so kind as to comment.

Bill

[Matthew Tucker]

does the bit of paper wedged in the corner fix the ticking sound? If not it may be coming from elsewhere. check A string nut slot and bridge slot too.

[bonaventura]

Originally Posted by Matthew Tucker

does the bit of paper wedged in the corner fix the ticking sound? If not it may be coming from elsewhere. check A string nut slot and bridge slot too.

Well, no. I've found the paper, if lying on the top, then vibrates, too. That actually "amplifies" the sound by extension.

But if I press on the "toe" of the bridge foot making the sound, then the ticking stops.

I can't believe no one else has had this...

[martinc]

bonaventura:

Greater minds than mine will likely weigh in here but I can't see how a bridge foot would "tick". There is enough pressure on the bridge from the strings to make enough contact without anything being loose enough to make a "tick"...especially between two substantial wood surfaces. A creak maybe but not a "tick".
The odds of it happening with two separate bridges are huge...and an indication that the problem is somewhere else.
I would check out your nut and string notches, tailpiece, tuners etc...the usual rattle list.
Also..maybe a string, your sound post or bass bar could be the cause.
In my experience the cause of small irritating noises is usually somewhere other than where you think they come from.
Trial and error is the only way I have been able to track them down.

[Martin Sheridan]

I agree that noises often come from other than where you think they are, but if the foot doesn't fit correctly that needs to be taken care of. That's why we have bass luthiers.

All of us in the trade have worked on a lot of basses that have had irregular, roughed up, gouged out areas under the bridge foot, but I think your inexperience is the issue. Worst case is you might have to put some new wood in there, but I doubt it.

[bonaventura]

Thanks, Matthew and martinc, for your thoughts. It probably isn't the bridge foot -- you're right, the chances of two bridges having the same tick is just too remote. The sound could be coming from a bridge groove -- the bridge tip is a bit wide, like 6mm. I'll check that out. But thanks for the comments.

In many years of inexperience I have learned one thing. Those who point to their experience in an effort to impress are often the fool. When something is not clear, ask a question. In this case, even my luthier next door -- who has been in the business 50+ years -- could not find the source of the sound after extensive checking.

If I find out what it is, I'll let you know.

[bonaventura]

I definitively located the source of this wierd sound. It is a rattling of the bridge foot on the table top in a small area in the NE corner of the E side bridge foot where the foot is not flush with the top. I can see the tiny gap there and after listening to it from various angles -- it is a sound that is difficult to locate -- this is clearly the source. Some fraction of a millimeter of wood needs to be scraped off the inside half of the foot bottom. I left the pencil line indicating the curvature of the bass top on the bridge after I fitted it, and this line too shows the differential that creates the gap.

As Arnold Schnitzer put it in another thread here on TB:

Originally Posted by arnoldschnitzer

Is it possible that when you lowered the "action" you twisted one of the bridge feet a little? If so, an edge of the foot could be rattling against the top where it is no longer flush. Also check all the seams.

If Arnold Schnitzer in his vast experience has encountered this problem, then for me my common sense view is confirmed and this thing is half solved. His statement [text in bold] confirms the view I was taking of where this sound might be coming from. In that thread, a TBer had a buzz coming from bridge area after lowering the string height. It may be that this "rattling" or "tikitikitiki" sound is not common but nonetheless does happen now and then. If there are bassists or even luthiers out there who have not encountered this problem, maybe this information will be useful for them.

[bonaventura]

Fixed it.

As described, the rattle or "ticking" sound or buzz was caused by a tiny gap between the outer edge of the E foot bottom and the curvature of the top. This is a "smaller" 3/4 bass with perhaps more marked curvature on the top than larger basses with more mass and gentler curves.

Initially, when I fitted the bridge in January, there was no buzz. But by May, a faint ticking sound was there, most audible when I pulled the open A string hard.

The sound got worse as summer wore on. I guess the top was rising slightly, and this widened the gap. By September, when the seasonal top rising usually peaks, I could slide paper almost a quarter inch in under that corner of the bridge foot, and the sound was very audible, affecting the overall sound of the bass.

Yesterday, with a big gig coming up next Saturday night, I had to face the music and finally find time to fix it or get it fixed.

The work was easier than I feared. In January, I had left on the foot the pencil line I drew on the bridge blank to show the top's curvature, and looking closely I could see I had not really done the job correctly because the wood was not scraped completely down exactly to the line uniformly across. All I had to do was carefully, slowly scrape another mm or so off the inside half of the foot bottom. It took about 6 or 7 lipstick impressions to get it perfect.

The rattle is gone and the tone and volume much better. This must be a common problem when bassists inexperienced in luthery try their hand at fitting a bass bridge. I learned a great deal here about my bass and how it works, which is why it's so satisfying to do this work. I wonder now if that was it, finito, or can the rattle return when the top goes down during winter? I guess I'll post again on that if it happens...

Thanks to all for your helpful comments.

[bonaventura]

after i went back in an "fixed" the bridge foot by scraping a mm or so off the inside bottom of the E string foot, the foot now fitting perfectly (100% contact! )

my joy was short-lived. a new buzz started.

the new buzz sounded different, and it's been over a month now listening to it, trying to pin point it. i finally wondered if there was some kind of sawdust under that foot. so yesterday off comes the bridge again. and yep, sure enough, there was dust and other residue under the foot.

i wiped off the top of the bass under the feet. there was lipstick left on it and an accumulation of sawdust clinging there and to the bottom of the foot, which i wiped off thoroughly with rubbing alcohol. after the foot dried, i reinstalled the bridge and ... am now buzz-free.

there is, by the way, a useful article on the web called "Buzz buzz buzz, i wonder why it does?" that deals in the main with violins and celli, but some of the insights apply to bass. it's at this address: http://www.abcviolins.com/buzz.html

[bonaventura]

Originally Posted by martinc

bonaventura:

Greater minds than mine will likely weigh in here but I can't see how a bridge foot would "tick". There is enough pressure on the bridge from the strings to make enough contact without anything being loose enough to make a "tick"...especially between two substantial wood surfaces. A creak maybe but not a "tick".
The odds of it happening with two separate bridges are huge...and an indication that the problem is somewhere else.
I would check out your nut and string notches, tailpiece, tuners etc...the usual rattle list.
Also..maybe a string, your sound post or bass bar could be the cause.
In my experience the cause of small irritating noises is usually somewhere other than where you think they come from.
Trial and error is the only way I have been able to track them down.

After fitting a new bridge in December 2007, my "tikitiki" sound, let's call it "the buzz" for lack of a better word, was back in May of 2008. It did not go away no matter how much I refined the fit of the E side foot. It was bothersome enough that I fitted another bridge in December 2008.

Now the buzz is back again since late May -- despite the fact that I have the current bridge fitted with the Moser adjusters that allow the feet to lie absolutely flat at all times. I am thinking that there is more going on here than meets the eye or ear. There is something seasonal happening with the top, and the sound is in fact coming from the E side foot, lower outside corner. If I place my finger on that corner, it stops.

So I returned to martinc's comments as the source of the tikikiki sound must be something else. Like martinc said, I am wondering if it might be the sound post, which I have placed pretty far out to the South and East of the G foot. If the sound post is too far out, I am thinking, maybe it doesn't give adequate support to the top, such that the E side bridge foot might not fit correctly and rattle a bit.

I'd be grateful for any comments/experiences with sound post placement and rattling under the E side of the bridge foot.

Bill

[1st Bass]

Are you game to try cutting a longer soundpost, and relocating to a point more in balance with the location at which the bassbar crosses the E-foot? Not actually seeing it, I have no idea just how far you really mean, but "pretty far out to the South and East of the G-foot" sounds an awful lot like someone who needs a new and longer soundpost fitted.

It really is interesting that pressing on that one corner of the bridge foot always makes the buzz go away, though...

Chet Bishop

[bonaventura]

Chet

I don't even really need to press, just touching that corner of the foot lightly stops the buzz.

The sound post is positioned about one sound-post width below the lower edge of the G side foot. That's the conventional placement in that regard.

But on the other hand, the inner edge of the sound post is almost 1 inch outside the outer edge of the G side foot. This is not your conventional spot as far as I can tell.

David Gage says the standard position is directly below the center of the bridge leg.

Does that give a better picture?

I may need to have a new sound post fit. But I don't want to do that unless necessary.

Bill

[1st Bass]

Well...soundpost setting isn't THAT hard...you could do it yourself. And, with your soundpost in that location, I would have said, a long time ago, that you need a longer soundpost, fitted closer to the centerline. I am assuming that your bassbar crosses the bass-side foot of the bridge?

Have you got a copy of Chuck Traeger's book? He has quite a bit about soundpost setting that is unconventional, and which I ignore, but still gives a fairly encouraging start toward the practice. I had set scores of them in smaller instruments, and a few in basses, before I ever got his book, so I already had some opinions about what was appropriate. I won't criticize him, but I will say that not everything he says is orthodox to most luthiers. I still found the book a truly valuable resource.

Get a piece of clear, fine-grained spruce, and plane out a round dowel, 3/4" in diameter, and longer than you need. I do not expect the properly-fitted new SP to be more than a milimeter or two over the length of the old one...maybe not that much. You want to keep looking through the endpin hole, and checking top and back fit-- it should be a full-contact fit on both plates, vertical (parallel with the corner blocks), and in the approprite location. Use a very sharp knife to trim it, until it is perfect. Some people shift to a sharp file, at the last.

A bass soundpost setter would be a very handy tool to have, but it is not absolutely necessary, if you are willing to carefully improvise. I forged my own bass soundpost setter, and have been very pleased with it. I eventually gave it away, so I need to make another. I cut it out of 5160 steel, then forged and ground it to the shape I wanted, and re-tempered it to spring-temper in the shank, and hard in the working heads.

Someone more experienced will surely chime in and give you more definitive instructions. (I hope)

Chet

[bonaventura]

Thanks Chet

Yes, I've got the Traeger book and will review it again.

I double-checked the sound post position last night and it is not as far out as I thought it was yesterday. Its inner edge is however just outside the bridge "toe" on the G string side. That would be fairly far out, is my guess. And as I recall it kind of popped into place when I set it about 18 months ago and might be too tight.

Can tightness like that be the cause of a buzzy sound emanating from the bridge foot on the E string side (only when plucking the A or E strings full force)?

Thanks for your response. I do not have the experience of many here on TB, and appreciate your friendly help.

Bill

[1st Bass]

Well-- if that is the only difference, I might be tempted to push the soundpost back toward center a bit, and see if it affects the buzz. I actually kind of doubt it will have the effect you want, though. Maybe reach in with a pencil on a stick and make a mark so you can find your way home later.

Frankly, I prefer a soundpost to be on the tight side-- possibly just my inexperience showing-- so maybe a little longer still will be in order ( I had REALLY hoped that Paul or Arnold, or Bob, or someone would step in by now... ahem!...).

I do think that location is too far "East", for sure...but I have a hard time imagining that this would make the buzz you describe.

Chet

[Jake deVilliers]

That soundpost is WAAAY too far afield Bill - time for a new one.

Does your ticking start right away or does it appear as the note blooms? As it decays?

[bonaventura]

Chet, Jake, and whoever else is reading this:

I came home tonight (from my "day job") and reset the soundpost in a last ditch effort to cure this pesty buzz or tikki sound that was emanating off the E string foot of the bridge. (Funny, how a "last ditch" effort is always where you find the solution).

Well, guess what? The sound post is now in the more conventional position: vertically directly under the G side bridge foot, about 1 sound post diameter below. It had been way too far out there, as you both said, and obviously it was way too tight. I don't think a new sound post is needed just yet, because in the new spot it stood by itself without any string pressure. After making sure it was flush with the top and back, I tightened the strings up.

And the buzz is gone.

It seems odd, but this whole problem was caused by the sound post being way out in Southeast territory, outside the G string side foot, which somehow created an imbalance that let the E side bridge foot vibrate loosely in a rattling manner against the top when the E and A strings were plucked full force. It was really hard to diagnose, because it sounded like it was coming off the FB or even from the upper bout. Maybe this thread will serve some one well in the future. This can happen when you don't set the sound post correctly.

But that's not all. The sound post now is in a better position for my bass because the bass opened up and even sounds a whole lot better. Fuller and louder. The bass vibrates much better. It's a great day for me because I've been working on this problem for about 18 months.

Thank you for your friendly input and thoughts.

Bill

[Jake deVilliers]

That's good news Bill - all's well that ends well, as that other Bill once wrote.

[Marcus Johnson]

Originally Posted by Jake deVilliers

That's good news Bill - all's well that ends well, as that other Bill once wrote.

[Jake deVilliers]

Noooo, the English one - The Bard, Shakespeare.