Weakness on the high E, 12th-15th fret?

[Craig Bumgarner]

I'm having a consistent problem over a number of guitars with a certain weakness on the high E string, frets 12 through 15. I've tried a lot of things to fix, but to date, not much luck.

The guitars are all 14 fret to body steel string guitars with a cutaway. When the E string is played hard with a rigid pick at the 12-15th, it sounds like they are fretting out. I question if this is really the case, or if it is, how it can be happening. The frets have been dressed, none high. I've tapered some relief in the finger board between the 12th and end of the fingerboard, so strung up, the fingerboard is straight over the body joint. I've used a neck jig that holds the neck in the strung up position for leveling frets. Necks are generally fairly stiff, 25-26mm at the 11th fret and CF rod reinforced. No visible hump at the neck join. Action is not particularly low, 2 - 2.5mm at the 12, high E. Raising the action actually seems to make it worse????

Strings are fairly light, the E is .010" but the scale is 670mm, so this is not a "slinky". Putting an .011" on does not help.

The only thing I can think of is that this area is over the most solid part of the guitar, the heel and neck block and maybe this is somehow absorbing the string energy. If so, I don't know what to do about it.

I'm out of ideas, any thoughts on this would be appreciated.

[Bob Gramann]

Is the saddle firmly seated all the way across? In other words, could you have a systematic error where the saddle slot isn't flat on the bottom?

[Craig Bumgarner]

Is the saddle firmly seated all the way across? In other words, could you have a systematic error where the saddle slot isn't flat on the bottom?

These are Selmer style guitars using a floating bridge like an archtop guitar and while saddles are sometimes used, I don't. Solid ebony or rosewood. The top edge of the bridge is slotted like a violin bridge. That doesn't mean the problem is not related to the bridge but the bridges are well fit to the top and the slots cut with a nut file of the appropriate size. Well, I say that, the string is .010" and the nut file is .012". Humm...... You would think the string would be thin enough to bite down into the wood and be secure.

[Bob Gramann]

And the fingerboard is firmly glued to the body? Selmer style is out of my range of experience.

[Craig Bumgarner]

And the fingerboard is firmly glued to the body? Selmer style is out of my range of experience.

When glued to the top, they are well glued. This is the standard Selmer style. I recently built two, going on three, with fully bolt-on necks. The bolt on necks are hump free at the body joint with no further work, but the problem persists with either method.

[Bob Gramann]

I've gone as far as I can go without having it in my hands. I would look for something loose somewhere in the loop between the fretted note and the bridge. If it's fine at fret 14 but weak at 15, I would look for a loose fret or a loose fingerboard extension or something soft or loose at the bridge. I don't expect this to have a positive answer but, if you tune the string to f and fret it at 14, is the note strong then? Good luck.

[Trevor Gore]

it sounds like they are fretting out...

Well, perhaps they are fretting out. Easy to check, use the old battery/LED trick. Wire up the battery and LED so a circuit is formed when the string hits the fret in front of the one you're playing on (LEDs (light emitting diodes) are faster and therefore more sensitive than old style flashlight globes).

[Al Dodson]

I don't think you want a slot at the bridge for the strings to pass through but just enough of a "nick" to keep them in place. I had a similar problem after changing strings recently (don't remember what string or frets). I do remember fooling around with the saddle slot fixed it.

[Michael Lewis]

Follow Al's advice and re do your saddle. If that doesn't remedy the problem then it may be frequency related. It may indicate some area needs to be lighter or heavier or stiffer etc. A lot depends on the mass and stiffness of your top and the same for the bracing. Maybe stiffening the back plate would help. Then again it may take a lot of little adjustments together to make it sing up high.

[Clay Schaeffer]

You could try inletting a small piece of bone unto the bridge under the e string, similar to what is done with ebony on maple violin bridges. The bone will give a harder wear surface and a more defined contact point.

[Craig Bumgarner]

Thanks Trevor for the LED idea. I had never heard of that, but rigged it up and tested. I can easily get the LED to light when I press down on the fret the wire is attached to but not getting anything when I play the fret below. Once or twice on a couple hundred hard pickings I got a tiny flicker (maybe, it is that tiny) but one once or twice. Trevor, what is the characteristic of the LED light when the string is fretting out? It occurs to me as I write this to try it in a dark room to be sure, but at this point I still thinking it is not fretting out.

Thanks Al and Michael regarding the bridge notch. It was about the depth of the string (.010") to start. I took the bridge top down so it was no more than half a string deep. The notch is now just a nick. No change though, I'm afraid.

I'm going to do some "research" on other guitars. Maybe it has more to do with my playing style than the guitar itself.

Craig

[Trevor Gore]

Trevor, what is the characteristic of the LED light when the string is fretting out?

Well, if your circuit is anything like as sensitive as mine (and why should it not be?) the LED lights pretty well immediately if there is any sort of problem. So I would be inclined to agree with you that that is not your problem.

Here's another simple test and depending how you installed the frets over the body may reveal a problem. Get a smallish, flat blade screwdriver (the one I use weighs ~ 40grams) and tap each fret with it, approximately under each string (i.e. six taps per fret). Listen for dead areas. You'll know it when you hear it. See if the dead-ringers correspond to the weak notes you hear on the first string (or other strings for that matter). Frets can un-seat for all sorts of reasons - e.g. not seating in the first place (especially problematic if fretting over the body), serial humidity changes, over enthusiastic fret dressing and the real sucker punch, over-heating them when power buffing them. Fixing "loose" frets usually involves glue. I run Titebond into the slots when I initially press the frets in, so never get those dead zones. If you only have a few dead areas, they can be fixed with CA, but that's not for the feint hearted.

[Craig Bumgarner]

Tevor, thanks for loose fret test. I'm very used to "percussion" testing, I use it all the time in my day job in a boatyard. I used the butt end of my pocket knife just now, all frets sound bright like knocking on a good piece of hardwood, no dead spots noticed. I press my frets into the fingerboard with a fret cawl, before gluing to the neck shaft. I have not been glued the full length of the frets when pressing but the ends of the tangs are exposed on the fingerboard edge and I fill in the little bit of slot left with CA, so I think the ends at least get glued.

[Trevor Gore]

I guess the good news is that that's another potential issue eliminated. I have no better news!

[Al Dodson]

Lets go back to the bridge again. Try less than 1/2 the depth of the string buried in a slot, especially on the unwound strings. Also, how wide is the bridge where the string passes over? I thinned mine to about 1/16" and then brought it up to a blunt point. My objective is to minimize the string to bridge contact. Good luck.

[Dick (DT) Trottier]

Hi Craig,
It could be you need a bit more relief, the problem on the nut end of the string. Try putting a capo at the 6th fret and see if the problem goes away.
Good luck...

[Matthew Atkinson]

Don't play up there!

[Michael Lewis]

In the first post you said these are steel string guitars, I assume a pin type bridge, not a trapeze type. If so, why are there notches for the strings in the saddle? You need notches in a floating bridge and in the nut but not a regular steel string saddle.

My guess as to the lack of lively response up high is too much material in a critical place. This could be just about anything, like braces that are too robust, too much mass in the bridge area, etc. There are a lot of unknowns here and we don't have the guitar in our hands to feel it's response.

Another reason for lack of high frequency response is too much internal damping, poor or loose glue joints, and lack of enough time spent vibrating. The use of a vibrator like a Tonerite or equivalent can help develop the potential of a structure to respond more efficiently. The process is called de-damping, and it can take several forms, like putting your guitar in front of speakers and turning the sound up, flexing the structure, and playing the tar out of it for a long while. Most musicians are familiar with "playing in" a new instrument, making it flex and move where it should when it is played. This is why older instruments can be so desired, because they have developed their potential over time. It is not how old the instrument is, it is how much and how hard it has been used.

[Kevin Bryden]

These guitars do have floating bridges Michael.

[Michael Lewis]

To quote Rosanna Rosanadana, "Oh, then never mind".<G>

Still, the dedamping exercise is pertinent.