Seeking luthier's advice

adarvas · #1 03-14-2010, 12:52 AM

Here is a weird one:

I really like the sound of my double bass but I always felt that the neck and the scroll resonates too freely on it. It seems that the focus and the fundamentals get lost, and I hear more of the sound of my finger than the notes. It doesn't seem to bother me as much with the bow but with pizz it does.

My fingerboard has just been dressed and it is getting thin. I assume that I new thick fb would help stiffen and control the neck. I have a heavy rubber mute and I jammed into the pegbox. Huge difference! Now the sound seems to emanate from the body not the neck. It's a lot easier to intonate and the neck is calm.
I did lose some volume but the overall sound has improved a lot.
Question: Do you think a new heavy fb would solve this, or should I graft two heavy wood plates to the head?

Any suggestions?

jonas · #2 03-14-2010, 12:09 PM

You may consider heavier tuning machines, or adding additional weight to the cheeks by using sheet metal.

I was told that there are basses with holes in the scroll, filled with lead to increase the weight. I never came across this, however.

Jonas

robobass · #3 03-14-2010, 12:21 PM

Quote:

Originally Posted by jonas

You may consider heavier tuning machines, or adding additional weight to the cheeks by using sheet metal.

I was told that there are basses with holes in the scroll, filled with lead to increase the weight. I never came across this, however.

Jonas

Good points. What kind of bass is it? A new FB will certainly help, but you have do decide if it's worth the investment. You also could look into a neck shim or a carbon fiber inlay under the board to stiffen things. Also consider getting a C-Extension. The added weight often improves situations like this, but you don't want to do this if you think you'll be replacing the FB soon. In the mean time, you could experiment with clamping weight to the scroll, and decide how much added mass is optimal.

adarvas · #4 03-15-2010, 12:11 AM

Thanks guys!
It's a carved bass, no label. Hungarian made, lots of character and like I said I like the sound, but...
I guess my intuition was right, though I would probably not drill holes for the led. I'm not a fan of the look of metal plates, and the machines are already heavy.
The carbon fibre is not a bad idea for stiffness but it weighs less than wood, so I'm not sure. I think I'll just try to get the thickest ebony board I can get, the neck has been altered and a bit too thin. Any more ideas?

Thanks again!

Eric Hochberg · #5 03-15-2010, 08:48 AM

Quote:

Originally Posted by adarvas

Here is a weird one:

I really like the sound of my double bass but I always felt that the neck and the scroll resonates too freely on it. It seems that the focus and the fundamentals get lost, and I hear more of the sound of my finger than the notes. It doesn't seem to bother me as much with the bow but with pizz it does.

I think maybe your assumption about the resonant neck and scroll may not necessarily be the cause of the sound issues. Before you do any work on the bass, why not take robo's suggestion and clamp some weights to the scroll? That should let you know if weight is the issue. I recently had a new FB put on my bass and I think the stiffer neck is helping with the response, but in terms of sound, the basic character hasn't changed although it seems a bit brighter now. That being said, a new thick FB with very little scoop is a beautiful thing!

adarvas · #6 03-15-2010, 10:31 PM

Clamping weights to the scroll is how I got the idea of sticking the mute in the pegbox. I put big paper clips on the tuning keys and I noticed that it calmed down the neck, so I went crazy with the mute.
It even tamed my G string, I don't get that scratch with the bow, and I noticed that my intonation is a lot better because I can hear more of the fundamentals.
I will keep experimenting, but I think I'm going for the new fb.

Square Bear · #7 03-15-2010, 10:52 PM

good points all around. maybe a wolftone modifier or sp adjustment will take care of the resonance issues. a new fingerboard will definitely help. also, have you listened while someone else plays your bass? an instrument sounds totally different from the other side. i would start with the simple fixes before you go altering things in more drastic ways.

**Matthew Tucker** · #8 03-15-2010, 11:57 PM

I would not add more weight to the scroll. Although I think that putting more weight on the scroll will dampen the resonance of the scroll, pushing more energy through the bridge, the same effect can be had by stiffening the neck assembly, and a new FB and graphite insert will do this without adding much weight. A new fingerboard is, as Eric says, a treat. But if you're going to that expense anyway, adding a carbon fibre insert is not much additional cost and will keep the neck stiff even when the new fingerboard has been dressed a few more times. The less the neck/scroll/ heel assembly can flex, the more string energy gets transferred through the bridge to the belly, resulting in a better sound.

robobass · #9 03-16-2010, 08:36 AM

Quote:

Originally Posted by Matthew Tucker

I would not add more weight to the scroll. Although I think that putting more weight on the scroll will dampen the resonance of the scroll, pushing more energy through the bridge, the same effect can be had by stiffening the neck assembly, and a new FB and graphite insert will do this without adding much weight. A new fingerboard is, as Eric says, a treat. But if you're going to that expense anyway, adding a carbon fibre insert is not much additional cost and will keep the neck stiff even when the new fingerboard has been dressed a few more times. The less the neck/scroll/ heel assembly can flex, the more string energy gets transferred through the bridge to the belly, resulting in a better sound.

More of the same. Two things though.

1. There is a huge range of scroll size and mass. Adding scroll weight sounds counterintuitive (I personally don't like huge scrolls - I suppose for this reason), but there are plenty of very good sounding basses with very big scrolls, so adding weight there cannot be discounted out of hand.

2. In these cash strapped times, I wouldn't rule out the a FB shim. You indicate that the board is marginal but the neck itself is definitely too thin. A good thick FB will likely solve your problems, but so might an 1/8" to 3/16" flat shim. Why not just add thickness? It will be way cheaper than a new board. How to decide if the board's worth saving? I don't know what would be a good objective test. Even a good thick board will visibly sink when you play the highest note on the D-string (the neckblock, ribs, and back are also flexible). What's important is how much the board bends above the neckblock when you do this.

In the end, a neck needs both mass and stiffness to do its job properly, but too much of either will be counterproductive. That's why - if I were in your position - I would begin with the cheapest option and go from there.

powerbass · #10 03-16-2010, 11:49 AM

I am not a luthier nor do I have much experience with DB, I have made several EB's so take what I say w/a grain of salt. What I am curious about is that w/the addition of a foam dampening device in the peg box the bass sounds better, the foam isn't stiffening the FB just dampen the strings from the nut to the tuners. In my experience the nut should stop any significant string vibration between the nut and tuners just as a bridge should limit the string vibration between bridge and tail piece. Perhaps the nut and string angle needs to be looked at as well?

**Matthew Tucker** · #11 03-16-2010, 01:19 PM

Quote:

Originally Posted by robobass

In these cash strapped times, I wouldn't rule out the a FB shim. [...] I would begin with the cheapest option and go from there.

I'd rule it out, 'cos I'm not so sure that a FB shim is going to be the cheapest option:
a) a thin FB can easily be damaged when it is removed,
b) there's still a fair bit of work involved and the big money is always in the work, not the materials.
c) even if you can re-use the old fingerboard, there doesn't sound like there's going to be any room for further adjustment. So you're going to need a new FB later anyway and remove the shim!

adarvas · #12 03-16-2010, 10:44 PM

I don't think I will try the shim precisely because I will definitely need a new fb. and I agree, it's the labour that cost so much.

I did try jamming foam into the pegbox and it does make a subtle difference, but I think I got better results with my mute. Thanks though, it was a good idea!