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  #1  
Old 01-03-2017, 02:07 PM
Bax Burgess Bax Burgess is offline
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Default Thuddish notes over body.

A guitar with a 14 fret to the body, bolt on neck. Moving up the board, fretted notes begin to tighten up at the 13 fret, with full on dullness from the 14 to the soundhole. What contributes to this?
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  #2  
Old 01-03-2017, 02:17 PM
Alan Carruth Alan Carruth is offline
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I'm sure you'll get lots of responses saying that it's the bolt-on neck, as if that were totally obvious. It certainly could be part of the problem, but without a LOT more information that's not certain. I've seen (and made) enough guitars with bolt-on necks that don't have any semblance of that trouble to be confident that it's not a kiss of death to tone and sustain above the body joint.
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Old 01-04-2017, 12:26 PM
Bax Burgess Bax Burgess is offline
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I'll figure that the structure is likely fine - the sole problem being a dropoff of the extended fingerboard, lending increasingly sharp notes. I have in mind to pull the first four, over the body frets, then refret with a taller crown. I then have to wonder if different fret material would sound out of sorts.
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Old 01-06-2017, 09:32 AM
Bax Burgess Bax Burgess is offline
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Not going to happen - my trying to work with higher frets. Too much dropoff of the fingerboard extension over the soundhole. I'll be depending on a luthier to fashion a new fingerboard. Nice guitar, though - a made in Mexico, Ehlers 15.
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Old 01-06-2017, 10:56 AM
redir redir is offline
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Well first of all, what does thuddish mean? What does tighten up mean, and what does dullness mean?

It's hard to use descriptive terms when regarding tone. I think dullness might make sense to most people. Is dullness a drop in volume? Sometimes you will see that but only one one fret because it's loose. To describe it as getting dull as you go up the neck is hard to understand.

I think I would categorize thuddish with dullness but tightening up is too abstract.

If the bolt on neck was loose I could conceive in my mind that would cause a problem. But that would also be very obvious.

I guess the obvious question is how old are the strings and what gauge are they? Also what type of guitar is it (body size shape)?
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Old 01-06-2017, 11:27 AM
Bax Burgess Bax Burgess is offline
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The neck is firm, fretboard straight, until the second fret over the body, at which point the board begins to curve downward as it extends out over the soundhole. By tightening up, I'm referring to the strings' reduction of movement, on the highest frets over the body, and the aural consideration that entails. However, that may be secondary to the increasing sharpness of the notes as they approach the end of the fingerboard, though, overall it probably adds to the disflavor of those notes - the thuddishness/dullness of the 'bum' note. The strings are a player in this as well. In addition to their being 11/52s, they are tuned down to CFCfac, which is doing them pretty spare favor as far as clarity, but it's a preference that I have settled on. And the guitar itself is a mini jumbo - 15" across.
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Old 01-06-2017, 12:23 PM
redir redir is offline
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Ok so as the fretboard starts to fall away the action is getting really high. If it's harder to fret notes there then could it be possible that you cannot fret it well enough to get a good tone? I've seen this with players who come in with super high action. They are not physically strong enough to fret the notes and as such they don't ring true.

It's a big enough guitar too so it could be perhaps that those high notes, short length of string which are light gauge and furthermore tuned slack, don't have enough energy to drive that top.

IDK I'm just guessing here.
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  #8  
Old 01-06-2017, 02:02 PM
charles Tauber charles Tauber is offline
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Not sure how helpful this is, but...

I had an Eastman guitar in for some setup work. I noticed that if I played the bass E string at the 12th fret - an E note - it had a very, very short sustain, a "thud", and almost no harmonic/overtone component to the note. If I played the same pitch on the A string, 7th fret, it had considerably more duration, less "thud" and more harmonic component. If I played the same pitch on the D string, second fret, it had far more sustain, far more harmonic content.

I found it sufficiently interesting that I recorded these three notes in Audacity to more clearly examine the response I was hearing.

I didn't find a cause and effect and eventually chalked it up to a "mediocre instrument". Not very insightful, but I found it interesting as it is rare to find an instrument with that striking a difference in response when playing the same pitch on different strings.

I've also had instruments that had a "thud" like response on notes fretted over the top - the fingerboard extension. I theorized that those notes were physically unsupported by the interior structure and the string's energy just dissipated. I did a few tests with soundpost-like pieces to attempt to bolster those specific frets, but didn't conclude anything specific, as in cause and effect. One of the places where I've seen this most is in fingerboards that are fully unsupported that extend into the soundhole, for extra frets for the top one or two strings.

In short, it probably has little to do with the situation you are encountering, but thought I'd throw it out there in case it stimulated some thoughts that might be relevant.
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  #9  
Old 01-06-2017, 02:34 PM
Truckjohn Truckjohn is offline
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I was also thinking insufficient fretboard support over the body. Does it have a "Popsicle brace" under the fretboard?
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  #10  
Old 01-07-2017, 12:53 PM
MC5C MC5C is offline
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So I just tried this on a flat-top 17" jumbo I happen to have out. It had clarity on most notes above the 12th fret, except for high G and F# on the low E string. They were dead and thuddy. One thing I do when looking at a dead note is sing that pitch into the soundhole of the instrument, if it resonates strongly back at me that tells me it's just the body resonance robbing the note of power, and there is little that can be done with it. But all the other notes were clear up to the end of the fretboard. So I would say look at the body resonance and see what it tells you. But - I suspect the main problem is lack of tension in the strings so no power at all with such a small mass of string available to vibrate. Your string tension is likely around 15 lbs per string, tuned that far down with such a light set. That's about half normal tension, so the instrument just doesn't stand a chance of working properly
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