I have had this idea for about a year but never tried it out for real until now. I have written about the bridge plate I do in spruce before on this forum and it's working great. But one thing didn't seem right. Between the ball end of the string (resting on top of a thin hardwood reinforcement around the string pin hole) and the underside of the hardwood bridge there was a whopping 7 mm of soft spruce. It was like having the ball end resting on a spring.

What I just did was to drill 8 mm holes through the spruce top (3 mm) and the spruce bridge (another 4 mm) and fill the hole with a stiff piece of a round birch dovel. I did this as an afterthought, next time I will drill the holes and glue the dovels before I glue the bridge. You only need to support the upper part where the ball end rests, the goal is to have only hardwood between the ball end and the bridge. May not be a good idea to have all the force from the ball end pressing on the birch dovel, it might make the bridge come loose...

I was amazed by the volume when I got the strings on the old European parlor. By far the loudest parlor guitar I have ever restored! The tone is clearer and the attack snappier too. Especially the two unwound strings sounded better.

This is a success and I'm sure any guitar with a standard maple bridge plate and a 3 mm spruce top will benefit even if my setup is unusual with that much spruce between the ball end and the underside of the bridge :-)

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Quite a process, Roger. I trust this has a salubrious effect on the sound, as I respect your abilities in the restoration of old Parlour Guitars! It's facinating to watch your methodology which you generously share here on the Forum.
I have an inquiry on the picture, it appears you repositioned the cross brace nearest the sound hole. It appears also to be new. Is this a sound improvement thing? I love the old ladder braced guitars, though they don't stay straight real well here where I live , with a very high humidity!

I do my own variant of ladder bracing. I always replace the old top bracing, I have found that the combination of old wood in the guitar and new wood in the bracing is a great combination. New wood is tough and strong, the old wood is brittle but have a better sound.

In Sweden we have the opposite problem, low humidity in the winter time, I don't know if my restorations will hold where you live.

I do an A frame around the soundhole. It's mostly for strength, the sound is not affected that much.

Been playing on the guitar a couple of days now. This guitar really have a lot of bite, each string delivers in spades when plucked. Better sustain is added to the list of new properties. The only drawback is that the volume is to high for me and my sensitive ears, after playing with my pick my ears gets a little numb... I haven't found anything bad to say about the tone though. It's all there, only louder and not as warm and cozy as before.

Next time I will make smaller 6 mm birch dovels to try to tame the volume, sometimes enough is enough.

What shall I call it? "Dovel booster", "Turbo plugs" or maybe "Eleven dovels"?


I decided to call it "turbo plugs" :-) Here are some slides of the finished victim of my experiment.

She looks very beautiful Roger.  I like the look of the black neck.  Is that ebonized, or stained?

It's black spirit varnish.

There is a quite interesting story behind it. Almost all European parlor guitars from 1870-1920 have this black painted necks. Never understood exactly why until I happened to restore an expensive Italian very fine parlor guitar from 1839. The neck was all covered in black ebony veneer! Amazing work considering it had a rounded pear shaped head for wooden pegs and an ice cone heel. The smooooothest neck I have ever played :-)

This black neck obviously became in fashion as a mark of quality and instead of gluing an shaping hard ebony veneer people made a cheap version with black varnish instead. The maple necks on these did not have a natural nice color as the mahogany necks in the old US made parlors from the same time, another reason for the black painted necks.

I wonder if it's a hangover from the veneered necks you see on old bowlback mandolins?

One last note. After a few more days of playing the "new" sound of the strings went away and the volume dropped with it. The high frequencies are boosted the most, still got more trebles than I'm used to. It mellowed down the volume nicely. Oh, it's sold now an on it's way to the buyer :-)

Thanks, I wish more people had the same attitude. I do a lot of things that are controversial in many eyes, but I do my best to respect the original builder - if the instrument deserves it. Everything I do I do for the sole purpose to improve the guitars sound and playability.

I have one customer in USA who has two GammelGura. He loves them both. Well. There is no problem shipping guitars between USA and Sweden except the cost of the shipping. And the fact that I have a queue of about 20 guitars to restore right now. Feel free to contact me ;-)

Got some feedback from the customer. I'm happy to say that he heard exactly the same thing as I did, more volume, clear tone and snappy response from the strings. He also noted great sustain high up on the fretboard (I never venture that far).


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