Flat and buzzy sound on repaired violin

[atshamblin]

  Fellow luthiers,

I have just finished repairing an old German strad copy, likely from the early 1900's. I got it for free from a junk box at the shop where I work, and it needed a lot of repairs to make it playable again. I have, (generally) in this order:

-Removed the broken neck

-glued and cleated a small crack on the edge of the saddle

-glued the C-bouts back on to the sides

-glued the top and bottom back on to the sides

-installed another old neck (in good condition)

-reglued the fingerboard

-made and installed a new heel

-fitted new pegs

-fitted a new bridge

-and fitted a new soundpost.

 

When I played it for the first time, what struck me was that the upper strings sounded pretty good, but the G and D strings were muted and buzzing, sounding like those of a 1/2 size violin. I tried everything to fix the problem, including:

-Changing out the strings, tailpiece, and end button (not all at once)

-removing the chinrest and fine tuners

-adjusting the soundpost

-adjusting the bridge and nut grooves

-checking the pegs for loose decorations

-checked for loose purfling

-checking the neck relief, string height, and nut height

-and pressing the bass bar with a soundpost setter

 

Yet the buzz and flat tone still persist. I kept the violin strung and correctly tuned for the past two days, and it still has a buzz, but the tone is nicer when plucked. My violin seems to have a thinner top and shorter sides than others, which might account for the flat tone, but the culprit of the buzz is still at large. If you have any ideas about how to fix this beautiful yet terrible-sounding violin, please tell me.

 

Photos:

https://goo.gl/photos/1oPhpr6bm9ddbvbd8

 

Thanks,

A.T. Shamblin

 

[uncle duke]

If it were me I would check the fingerboard height above the belly again to make sure the back is not giving away, assume I have inferior quality belly wood and put a glob of plumbers putty or tape a weight to the underneath cove side e and a string area and see what changes that would make. 

 

Are you sure the saddle crack area didn't go farther in.  Note- I'm not an authority but these are things I would check.  Also, is the fingerboard ebony or other type of wood?

[Michael Richwine]

Does it buzz only on open strings, or on stopped strings as well?

[atshamblin]

Does it buzz only on open strings, or on stopped strings as well?

The open strings have a slight buzz, but when it is stopped the buzz is very noticeable.

[atshamblin]

If it were me I would check the fingerboard height above the belly again to make sure the back is not giving away, assume I have inferior quality belly wood and put a glob of plumbers putty or tape a weight to the underneath cove side e and a string area and see what changes that would make. 

 

Are you sure the saddle crack area didn't go farther in.  Note- I'm not an authority but these are things I would check.  Also, is the fingerboard ebony or other type of wood?

The fingerboard is rosewood, and when I press on it, the buzz becomes less noticeable. The fingerboard height is within MENC specifations, and the back seems to be solidly glued. I'll try regluing the fingerboard this weekend and see what that does to the tone. 

Thanks for your help!

[Brad H]

It sounds like the fingerboard playing surface is not properly shaped/scooped.  Most often, I find that humped fingerboards go hand in hand with  neck surfaces that are humped.   Are you sure the neck surface was flat before gluing on the FB?

[franciscus]

In the pretty extensive list of repair in the OP, I have not seen the bass bar mentioned. I do not think that the problematic bass bars cause the buzz often, but it is not impossible.

[MaestronetLurker]

Check the fingerboard with a 6" straight edge to see if there are flat spots or bumps that don't show up with a longer straight edge.

Also, quoting MENC spec tends to lump you together with the low end junk violin dealers with adds such as "exceeds MENC specifications". They published those specs in the 1950's and if you call them today to get a copy of the specs they will have no idea what you're talking about. The numbers may be fine, but the people that I have seen quote them are not quality dealers. Also, there's a difference in spec between steel core strings and synthetic core strings. If you are using steel string specs with a Dominant string, for example, then you'll have a buzz. Synthetic strings are wound with metal, but are not what they mean when they say steel string.

Synthetic string spec E 3-3.5mm G 5-5.5mm

I'm also suspicious of the button on that violin. If it is t grafted into the back, then you don't have enough strength there. Can't tell from the photo, but it doesn't look like what I expect from a button graft.

[atshamblin]

It sounds like the fingerboard playing surface is not properly shaped/scooped.  Most often, I find that humped fingerboards go hand in hand with  neck surfaces that are humped.   Are you sure the neck surface was flat before gluing on the FB?

 

 

Check the fingerboard with a 6" straight edge to see if there are flat spots or bumps that don't show up with a longer straight edge.

Also, quoting MENC spec tends to lump you together with the low end junk violin dealers with adds such as "exceeds MENC specifications". They published those specs in the 1950's and if you call them today to get a copy of the specs they will have no idea what you're talking about. The numbers may be fine, but the people that I have seen quote them are not quality dealers. Also, there's a difference in spec between steel core strings and synthetic core strings. If you are using steel string specs with a Dominant string, for example, then you'll have a buzz. Synthetic strings are wound with metal, but are not what they mean when they say steel string.

Synthetic string spec E 3-3.5mm G 5-5.5mm

I'm also suspicious of the button on that violin. If it is t grafted into the back, then you don't have enough strength there. Can't tell from the photo, but it doesn't look like what I expect from a button graft.

 

The fingerboard is shaped right, but the neck surface curves upwards very slightly near the headstock. 

That's interesting about the use of MENC standards. At the shop I work at, we use them as guidelines, and I shaped the bridge with the synthetic string specs in mind. I put the button in place for cosmetic reasons, wood gluing it to the back and hide gluing it to the neck. This violin was not worth quite enough to me to go through the process of cleating the button's joint with the back.

[MaestronetLurker]

The fingerboard is shaped right, but the neck surface curves upwards very slightly near the headstock. 

That's interesting about the use of MENC standards. At the shop I work at, we use them as guidelines, and I shaped the bridge with the synthetic string specs in mind. I put the button in place for cosmetic reasons, wood gluing it to the back and hide gluing it to the neck. This violin was not worth quite enough to me to go through the process of cleating the button's joint with the back.

I'd say that calling the pegbox a headstock is also a faux pas in the violin world for what it's worth.

The button joint you describe is worthless for the strength of the neck. Without a proper neck joint there's no point in troubleshooting tonal issues. Unlike a guitar dovetail the violin requires the button as an integral part of the joint.