Problem with a brand new banjo, 11" calfskin head, hookless rim. 1st string goes sharp 7th fret onwards. All other strings intonate fine. Tried with capo, still the same so not the nut. Tried different bridges and strings still the same. Any help with this would be appreciated.
quote:
Originally posted by Kieranf777Problem with a brand new banjo, 11" calfskin head, hookless rim. 1st string goes sharp 7th fret onwards. All other strings intonate fine. Tried with capo, still the same so not the nut. Tried different bridges and strings still the same. Any help with this would be appreciated.
Thanks but I have tried most avenues for correcting intonation. I have been playing 15 years and haven't come across one this stubborn
Change the string, the one you have is likely false.
If it's a new banjo it might be under warranty, in which case you should be able to get your money back or receive a new banjo that plays correctly. If this isn't the case, read on...
Could you please list what checks you have made? These are what I always try:
- Bridge placement
- Straightness of neck
- Is the fretboard in the same plane as the bridge and head? Had some problems when I didn't tighten the nut for the neck-pot connection properly, leading to a slight neck twist and all kinds of interesting problems
- Action too high maybe on the 1st string?
- Fretting too hard? Perform intonation with the lightest force needed to fret cleanly
Unless the frets are placed incorrectly (extremely rare even on low-end banjos), maybe some frets need to be recrowned to move the apex of the fret a little? This is probably a luthier job – but if it's a decent banjo, you'll probably want to hand it to a luthier anyway for some hands-on troubleshooting.
So far I have tried
Bridge placement and rotation
Different strings
Capo to rule out the nut
Head tension
3 different bridges of various heights
Lighter fretting
It's a high end banjo with an ebony wedge through the dowel stick that holds the neck to the pot. It's imported from the USA so perhaps something went wrong during transit.
"1st string goes sharp 7th fret onwards. All other strings intonate fine. Tried with capo, still the same"
What happens when you put the capo at the 4th fret? Same sharp on 1st string, others OK?
"Bridge placement and rotation "
Does this mean that no matter where you put the bridge, the 1st string is always sharp?
If you are using an electronic tuner, and information on how sharp the 1st string is, compared to the other strings with accurate intonation?
Do others hear the sharpness of the 1st string?
Well when I moved the bridge toward the tailpiece enough the 1st string intonates correctly and the rest are flat.
However earlier today I reduced the head tension and installed a 5/8 bridge. After a few hours to settle it has greatly improved which is weird because I thought it would get worse with less tension. Thanks for the assistance anyway. I'm glad it wasn't the frets or neck.
"However earlier today I reduced the head tension and installed a 5/8 bridge. After a few hours to settle it has greatly improved"
So lets take a look at what changed:
1. The head tension lowered, which would reduce the strength of the high notes and also lower the string height.
2. 5/8" bridge, which would reduce the string height, and also possible change the tone of the 1st string and other strings.
3. The string height itself (due to #1 and #2), which by being lower decreases the sharpness of the string when fretting it.
One thing to check with a new banjo is if the fingerboard is parallel to the head -- i.e., the neck is not twisted. If the neck is twisted such that the 1st string side is lower than the 5th string side, then the string height on the 1st string would be the greatest of all the strings and thus more likely to go sharp when fretting.
I don't know without having the banjo in my hands. Normal "scientific" investigation is that if faced with a situation that appears to be impossible, most likely some data points are being overlooked. You changed something with the head tension and new bridge that contained some new data points. 
You mention that the first string got sharp after the 7th fret. And that you did bridge placement. Sounds like you didn't do bridge placement correctly. To place the bridge properly, First measure from the nut to the 12 fret. Use a ruler of a piece of string. Then take that same measure and extend it from the 12 fret toward the bridge. The innermost edge of the bridge where the 1st string rests should be equal to the length from the nut to the 12th fret. After doing that, put the 1st string into tune (D4). Once the 1st string is in tune, press down at the twelfth fret and see if it is still in tune for a D5. If it is sharp, move just the edge where the 1st string rest towards the tailpiece a bit, maybe an 1/8". Test again. Still sharp? Move it a bit more until the 1st string is in tune both open and at the 12th fret. Now if the 1st string was flat at the 12th fret you would nudge the end of the bridge holding the 1st string closer to the next, and testing until both open and 12 frets are in tune.
Now you need to get the 4th string in tune. Check the fourth string and get it in tune. Now press at the 12th fret. If it's sharp, nudge the end where the 4th string rest towards the tailpiece, taking great care not to change the position of the end where the 1st string rests. This is very crucial, otherwise you'll have to go back and retune the 1st string again. I'd suggest that when you're adjusting the bridge for 4th string tuning that you use one hand to hold the bridge at the 1st string in place while moving the end with the 4th string.
Keep adjusting the end of the bridge with the 4th string by nudging it toward the tailpiece until it is no long sharp. Now if the 4th string is initially flat, as with the 1st string, nudge it towards the neck. When you have your 4th string perfectly in tune open and pressed at the 12 fret, go and make sure your 1st string is still in tune. If not, make a minor adjust to that end of the bridge.
Once you have the 1st and 4th strings in tune, you can tune the 2nd, 3rd and 5th strings. It's not unusually to have the bridge at a angle to manage intonation. This is necessary because the lower tone strings are thicker.
Hello,
Site down the third string. This should be a straight line. If not, the tailpiece needs to move until it is centered.
The puzzle is that only the 1st string is out of tune, and only from the 7th fret up. All the other strings at all frets are ok, according to the poster.
I have had confusing tuner readings similar to Kieran's that were caused by sympathetic vibrations from adjacent strings. The solution was to dampen all the strings except the one being tuned.
That's another good data point. Is the sharpness being heard, measured, or both?
In this case it was irritatingly sharp by ear and only the first string. No amount of bridge fiddling solved it. Turns out simply decreasing head tension worked. It is a relatively unusual design being hookless and dowel stick with a wedge which is why I posed the question on here. Thanks to all for input
