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  #1  
Old 12-12-2016, 11:04 PM
t_wang t_wang is offline
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Question An annoying resonance

Hi...first post here, and hoping for a bit of help. A short while ago, I purchased an inexpensive acoustic/electric, an Ibanez AEG12II. Not exactly top drawer, but had some good points. Has the thinner acoustic body, easy to hold, seems decently put together, electronics work well. I was especially fond of the crisp clear voice, and the neck was the best I have had for quite a while. But....now after about 6 months, there is a rather disturbing resonance on the open B string, which also occurs when the same B is fretted on the G string. My first guess was something loose inside, so I loosened the strings, pulled the pins, and had a look around inside with a mirror. Then I got my hand in there and tested all the bracing. Everything seemed tidy and solid. Next, I made sure that the wiring was dressed up inside and not flopping around, then re-installed string ends and pins and retuned. Still gets that overtone on the B.
At this point, I cannot find the culprit for this resonance. The strings are the originals, which were advertised to be D'adarrio, and are starting to lose their bright sound. Could it be as easy as replacing strings? Or is it more of a structural dilemma? I would be grateful for any advice to troubleshoot this problem. I do like the guitar, but if it's hopeless, I'll let it go. Thanks
in advance.
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  #2  
Old 12-13-2016, 03:53 AM
Bill Yellow Bill Yellow is offline
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Do you get the buzzing when a jack plug is inserted, or only when not?
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Old 12-13-2016, 07:24 AM
Earl49 Earl49 is offline
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Try weaving a piece of felt or cloth between the strings above the nut. Could be that simple.....
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Old 12-13-2016, 10:53 AM
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Change the strings. It's quick and easy, and there's a reasonable chance they are the problem. From what you posted, the strings are six months old.
There are other possible causes, but the strings are the first thing to check, especially if they're six months old.
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Old 12-13-2016, 11:09 AM
jbbgibson jbbgibson is offline
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I agree. Go for the strings first. As strings age they develop more overtones. One way you can see this is with electronic tuners. As they get older the note on the tuner appears to "bounce around" the target note and is harder to dial in.

The overtone when fingering the B note on the G string could very easily be sympathy overtones produced on the actual B string.

Another, less common source can be either the saddle or nut. If either does not have a good edge then some unwanted contact can occur. Check the saddle to see if it is rounded too softly at the top. If the curve is not sharp enough then the vibrating string can be making contact just in front of the saddle edge and producing something that sounds like an overtone with a slight buzz. Same thing can happen on the nut end. I see both of these conditions mostly when inexperienced people try to make changes to them.

My saddles use an edge with very little rounding. In fact it can be hard to tell its there unless you look close.
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Old 12-13-2016, 12:53 PM
Alan Carruth Alan Carruth is offline
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Since the problem is pitch related, it could be some sort of 'wolf' note: it may have developed a resonance at that pitch which 'plays badly' with the rest of the guitar. It could also be any on of a number of things such as you have already checked. I've had terrible buzzes caused by very small loose parts, and these can be a nightmare to track down. The only consolation is that, once found, such things are often easy to fix.
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Old 12-13-2016, 01:39 PM
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I'm wondering if it could be sympathetic coupling. Specifically, the open b string (or fretted b note on the g string) setting the low E string in motion. That b note frequency is 3 times the frequency of the open E.

Try damping the low E string when you play the b note.

There is a similar relationship to other notes and other open strings. The high e string frequency is 3 times the frequency of the open A string. The a note on the 5th fret of the high e string is 3 times the frequency of the open D string. One of my guitars has a high level of this sympathetic coupling and I can hear the open E, A, or D string vibrating if the 'related other note' is played.
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Old 12-13-2016, 04:55 PM
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Thread title is a great description of Yoko Ono.

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Old 12-13-2016, 05:43 PM
Arumako Arumako is offline
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Quote:
Originally Posted by Bob Womack View Post
Thread title is a great description of Yoko Ono.

Bob
Was seriously engaging this thread, feeling all kinds of sympathy for t_wang! Wasn't expecting "her" to turn-up here! Jeez...just about snorted coffee out of my nose! LOL!
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  #10  
Old 12-13-2016, 09:50 PM
t_wang t_wang is offline
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Wow, thanks for all responses, some good stuff there. I ruled out the jack; saddle and nut are actually quite crisp, so no wobbles there. It WAS a wolf tone of sorts as suggested by Alan, and I did notice the sympathetic effect on the other strings, especially the low E, as rightly mentioned by ChuckS. Interesting that even when the other strings were dampened, the B tone would still have a heightened 'muddy' sound. Anyway, I changed out the strings, and installed silk n steel in place of light gauge bronze, and it seems to have diminished quite a lot. I can live with it now. So thanks much to all, I am grateful for the combined knowledge infusion.
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  #11  
Old 12-15-2016, 03:51 AM
buyemblind buyemblind is offline
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Quote:
Originally Posted by jbbgibson View Post
I agree. Go for the strings first. As strings age they develop more overtones. One way you can see this is with electronic tuners. As they get older the note on the tuner appears to "bounce around" the target note and is harder to dial in.

The overtone when fingering the B note on the G string could very easily be sympathy overtones produced on the actual B string.

Another, less common source can be either the saddle or nut. If either does not have a good edge then some unwanted contact can occur. Check the saddle to see if it is rounded too softly at the top. If the curve is not sharp enough then the vibrating string can be making contact just in front of the saddle edge and producing something that sounds like an overtone with a slight buzz. Same thing can happen on the nut end. I see both of these conditions mostly when inexperienced people try to make changes to them.

My saddles use an edge with very little rounding. In fact it can be hard to tell its there unless you look close.
This happened to me, the soft wrap on the nut side of the saddle. took me forever to find it.
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