D string going sharp

Dfyngravity · 11-03-2009, 07:24 AM

I am having a problem with my D string. The top D string (closest to the G) goes sharp as I fret it. Both are tuned perfectly but the top one is going shape. I typically play J74's but I just switched to the Labella JM11 strings which are smaller in gauge and flatwound, so I wouldn't think it would be catching on the nut or bridge slot but it must be. I used a little wax to grease up the slots but that didn't do anything. Do I really need to widen the slots even though I am using a smaller gauge? Do you think it is catching on the bottom of the slot as it probably sits a little deeper in the slot since its a smaller gauge? Any thoughts out there?

Dave Cohen · 11-03-2009, 09:32 AM

The E-1st and A-2nd strings are the same with the J11s as they are in the J74s, but the D-3rd and G-4th are flatwound and considerably smaller on the JM11s. You may need a differently compensated bridge saddle for the JM11s to get the best possible intonation all the way up the fingerboard. On the D-3rd, have you compared the harmonic at the 12th fret to the fretted note at the 12th fret with a tuner?

http://www.Cohenmando.com

hank · 11-03-2009, 10:09 AM

Sounds like you've already done this with wax but if you have one of the pieces of extra D string you cut from the post you can use it like a rasp/file in the bridge and nut slots after cleaning out the wax and replacing with graphite (tube or pencil lead). I do this when tuning seems erratic and suspect binding. Seems to free the slots of any burrs and bond the lubricant. It's possible this particular string is defective. If it was intonation wouldn't it affect both D strings?

Dave Cohen · 11-03-2009, 10:26 AM

Hank is right about the defective string(s) thing. I didn't read your post as carefully as I might have. I just had that happen with some LaBella wound 0.014" A strings. Replaced 'em w/ some 0.014" plain steel strings, and they were in tune w/ each other. I'm speculating that the smaller the flatwound string diameter, the more difficult it is to get consistent quality control. Had the same thing happen w/ some D'Addario flatwound 'dola strings once. That may be why T/I charges so much for theirs - the extra effort put into quality control.

http://www.Cohenmando.com

allenhopkins · 11-03-2009, 10:39 AM

Quote:

Originally Posted by Dfyngravity

I am having a problem with my D string. The top D string (closest to the G) goes sharp as I fret it. Both are tuned perfectly but the top one is going sharp.

Not sure I understand the problem. You say that the two D strings are tuned in unison when you don't fret them, but when you fret them, one string sounds sharp (the G on the 5th fret is closer to Ab), but the other doesn't?

String binding in the nut slot wouldn't cause this. What happens with string binding, is that there's more tension on the string in the portion between the tuning peg and the nut, and as you pick the string, it "works" in the slot and the extra tension is transferred to the portion between the nut and the bridge (the portion that sounds), and the string goes sharp. That doesn't sound like the problem you're describing.

What you seem to be getting is improper intonation on one of the D strings. Could be an improperly compensated bridge saddle, or a defective string. If two D strings sound in unison unfretted, but show a discrepancy when you fret them, the problem is that the length of string between the fret and the bridge is varying between the two strings, IMHO.

sloanypal · 11-03-2009, 10:50 AM

I just put a new set of JM11's on last night and had the same problem with the D strings. They could be tuned in unison but one would go sharp when fretted. I had two sets so I swapped out that string. It was indeed a defective string.

Dfyngravity · 11-03-2009, 03:03 PM

I figured it was a defective string. I initially thought it was the string because to the naked eye it almost looks as if the two strings are slightly different in gauge, but I am not certain. But then I though maybe it was something with the nut or saddle so I greased em up but nothing. I am going to try and switch out the problematic string and see what happens....thankfully I bought two sets.

Dfyngravity · 11-03-2009, 03:22 PM

Well I changed the string and it seems as if that did it. Hmmmm I really do like these strings, but I am not sure if I want to buy two sets everytime....

DougC · 11-03-2009, 03:35 PM

This seems to be a common problem with a number of brands. (string not in tune - bad string)

EdHanrahan · 11-03-2009, 03:58 PM

Ted Eschlimann (spell?) who runs JazzMando is here on the Cafe, and with a great reputation. I'd approach him.

Ted Eschliman · 11-03-2009, 04:36 PM

D-string problem. Definitely the string. I'll take care of anyone who bought strings from me who might be having this problem. Please email me.

Dr. Dave is correct; these strings are hard to make, but that's not an excuse for them to be faulty. I've got Labella backing me up on this; it's a credit to their reputation to make things right.

DerTiefster · 11-04-2009, 10:37 PM

I had a problem on a mandola recently, but on the bass strings. I'm a physicist and was intrigued by the issue, so I inquired a bit more. In my case, the strings were as close to identically tuned as I could get when open, but were about 2 Hz (maybe 3 Hz) apart when fretted on the 12th fret. I estimated this frequency difference from the beat frequency (the wah-wah-wah warble you hear plucking both was 2-3 ocsillations per second). Length x frequency is constant for constant tension and string mass, so at middle C this is a 1% variation in frequency. I looked at the bridge to see whether 1% of the distance from 12th fret to bridge was a reasonable thing to attribute to an asymmetry in the two bass strings (pushing close to a couple of millimeters). It wasn't, so it had to be the string. I then loosened the strings and without detaching them from the posts or tailpiece, flopped them into each other's nut and bridge slots. The formerly flat string remained flat, so it could not be the instrument and had to be (one of) the strings. I'll find out soon which one.

I mention this for people who suffer from such things so they can make these estimates and conclude for themselves in their particular case just what the problem is. I hope it's helpful for someone. I fussed with my particular issue for quite some time before I sat down to really tease out the truth.

11-03-2009, 07:24 AM	#1
Dfyngravity Ben Beran Join Date: Jan 2004 Location: Richmond, VA Posts: 1,079	D string going sharp I am having a problem with my D string. The top D string (closest to the G) goes sharp as I fret it. Both are tuned perfectly but the top one is going shape. I typically play J74's but I just switched to the Labella JM11 strings which are smaller in gauge and flatwound, so I wouldn't think it would be catching on the nut or bridge slot but it must be. I used a little wax to grease up the slots but that didn't do anything. Do I really need to widen the slots even though I am using a smaller gauge? Do you think it is catching on the bottom of the slot as it probably sits a little deeper in the slot since its a smaller gauge? Any thoughts out there? __________________ Give me my mandolin and a beer and I'll be content

11-03-2009, 09:32 AM	#2
Dave Cohen Registered User Join Date: Sep 2002 Location: Richmond, VA Posts: 1,084	Re: D string going sharp The E-1st and A-2nd strings are the same with the J11s as they are in the J74s, but the D-3rd and G-4th are flatwound and considerably smaller on the JM11s. You may need a differently compensated bridge saddle for the JM11s to get the best possible intonation all the way up the fingerboard. On the D-3rd, have you compared the harmonic at the 12th fret to the fretted note at the 12th fret with a tuner? http://www.Cohenmando.com

11-03-2009, 10:09 AM	#3
hank Henry Lawton Join Date: May 2009 Location: Greenwood, Ar Posts: 286	Re: D string going sharp Sounds like you've already done this with wax but if you have one of the pieces of extra D string you cut from the post you can use it like a rasp/file in the bridge and nut slots after cleaning out the wax and replacing with graphite (tube or pencil lead). I do this when tuning seems erratic and suspect binding. Seems to free the slots of any burrs and bond the lubricant. It's possible this particular string is defective. If it was intonation wouldn't it affect both D strings?

11-03-2009, 10:26 AM	#4
Dave Cohen Registered User Join Date: Sep 2002 Location: Richmond, VA Posts: 1,084	Re: D string going sharp Hank is right about the defective string(s) thing. I didn't read your post as carefully as I might have. I just had that happen with some LaBella wound 0.014" A strings. Replaced 'em w/ some 0.014" plain steel strings, and they were in tune w/ each other. I'm speculating that the smaller the flatwound string diameter, the more difficult it is to get consistent quality control. Had the same thing happen w/ some D'Addario flatwound 'dola strings once. That may be why T/I charges so much for theirs - the extra effort put into quality control. http://www.Cohenmando.com

11-03-2009, 10:50 AM	#6
sloanypal Registered User Join Date: Jul 2007 Location: Minneapolis, MN Posts: 20	Re: D string going sharp I just put a new set of JM11's on last night and had the same problem with the D strings. They could be tuned in unison but one would go sharp when fretted. I had two sets so I swapped out that string. It was indeed a defective string. __________________ Sloan Hamilton 2003 Gibson F9 1971 Gibson EM200

11-03-2009, 03:03 PM	#7
Dfyngravity Ben Beran Join Date: Jan 2004 Location: Richmond, VA Posts: 1,079	Re: D string going sharp I figured it was a defective string. I initially thought it was the string because to the naked eye it almost looks as if the two strings are slightly different in gauge, but I am not certain. But then I though maybe it was something with the nut or saddle so I greased em up but nothing. I am going to try and switch out the problematic string and see what happens....thankfully I bought two sets. __________________ Give me my mandolin and a beer and I'll be content

11-03-2009, 03:22 PM	#8
Dfyngravity Ben Beran Join Date: Jan 2004 Location: Richmond, VA Posts: 1,079	Re: D string going sharp Well I changed the string and it seems as if that did it. Hmmmm I really do like these strings, but I am not sure if I want to buy two sets everytime.... __________________ Give me my mandolin and a beer and I'll be content

11-03-2009, 03:35 PM	#9
DougC Registered User Join Date: Jan 2008 Location: Minneapolis, MN Posts: 185	Re: D string going sharp This seems to be a common problem with a number of brands. (string not in tune - bad string)

11-03-2009, 03:58 PM	#10
EdHanrahan Wayfarin' Stranger Join Date: Dec 2008 Location: Over the Hudson & thru the woods from NYC Posts: 188	Re: D string going sharp Ted Eschlimann (spell?) who runs JazzMando is here on the Cafe, and with a great reputation. I'd approach him. __________________ - Ed "What our group lacks in musicianship is offset by our willingness to humiliate ourselves." - David Hochman

11-03-2009, 04:36 PM	#11
Ted Eschliman Chief Moderator/Shepherd Join Date: Sep 2002 Location: Lincoln, NE Posts: 3,339 Blog Entries: 2	Re: D string going sharp D-string problem. Definitely the string. I'll take care of anyone who bought strings from me who might be having this problem. Please email me. Dr. Dave is correct; these strings are hard to make, but that's not an excuse for them to be faulty. I've got Labella backing me up on this; it's a credit to their reputation to make things right. __________________ Ted Eschliman About Us www.JazzMando.com Author, Getting Into Jazz Mandolin Facebook: FFcP support group Twitter: @FFcPmandolin

11-04-2009, 10:37 PM	#12
DerTiefster the little guy Join Date: Jan 2009 Location: S.E. Virginia Posts: 153	Re: D string going sharp I had a problem on a mandola recently, but on the bass strings. I'm a physicist and was intrigued by the issue, so I inquired a bit more. In my case, the strings were as close to identically tuned as I could get when open, but were about 2 Hz (maybe 3 Hz) apart when fretted on the 12th fret. I estimated this frequency difference from the beat frequency (the wah-wah-wah warble you hear plucking both was 2-3 ocsillations per second). Length x frequency is constant for constant tension and string mass, so at middle C this is a 1% variation in frequency. I looked at the bridge to see whether 1% of the distance from 12th fret to bridge was a reasonable thing to attribute to an asymmetry in the two bass strings (pushing close to a couple of millimeters). It wasn't, so it had to be the string. I then loosened the strings and without detaching them from the posts or tailpiece, flopped them into each other's nut and bridge slots. The formerly flat string remained flat, so it could not be the instrument and had to be (one of) the strings. I'll find out soon which one. I mention this for people who suffer from such things so they can make these estimates and conclude for themselves in their particular case just what the problem is. I hope it's helpful for someone. I fussed with my particular issue for quite some time before I sat down to really tease out the truth. __________________ Michael Tiefenback