Need help with wolf tone...

[Troisnoir]

If I'm using the term properly, I seem to half a substantial wolf tone in my guitar.

More specifically, I get a loud resonance/vibration in the guitar, specifically the top. It happens to be an F note, and it doesn't matter where I play the pitch, I still get the resonance. It's louder on my open G string (I tune down to D standard tuning), but I can duplicate it on other strings at the appropriate fret.

Assuming I don't have a loose brace or part (doesn't appear to so far), is a wolf tone something that can be corrected after the fact, that is, after the guitar has been completed? (That would eliminate design changes, etc.)

Or do I just have to live with it?

FYI: As I have been troubleshooting this over several years, I have altered the neck angle, saddle height, pitch I tune to (D, Eb, E), string guage, string break angle over the saddle, etc.

These changes seemed to affect the volume/pitch/severity of the wolf tones, but nothing ever eliminated them.

Also, I get some sort of resonance, usually, on the high E, the B and the G strings, with varying volumes/intensities, and not necessarily all at an F note. But the strongest occurrence is at F.

If nothing is actually broken or defective, is there anything I can do?

[Ned Milburn]

Originally Posted by Troisnoir

If I'm using the term properly, I seem to half a substantial wolf tone in my guitar.

More specifically, I get a loud resonance/vibration in the guitar, specifically the top. It happens to be an F note, and it doesn't matter where I play the pitch, I still get the resonance. It's louder on my open G string (I tune down to D standard tuning), but I can duplicate it on other strings at the appropriate fret.

Assuming I don't have a loose brace or part (doesn't appear to so far), is a wolf tone something that can be corrected after the fact, that is, after the guitar has been completed? (That would eliminate design changes, etc.)

Or do I just have to live with it?

FYI: As I have been troubleshooting this over several years, I have altered the neck angle, saddle height, pitch I tune to (D, Eb, E), string guage, string break angle over the saddle, etc.

These changes seemed to affect the volume/pitch/severity of the wolf tones, but nothing ever eliminated them.

Also, I get some sort of resonance, usually, on the high E, the B and the G strings, with varying volumes/intensities, and not necessarily all at an F note. But the strongest occurrence is at F.

If nothing is actually broken or defective, is there anything I can do?

The wolf tone will be more related to the soundboard design (thickness & bracing) as well as the body volume and sound-hole. Other than altering one or several of these, it will be difficult to rectify the wolf tone as you describe. Eliminating wolf tones and creating a "balanced" instrument is a pursuit of guitar makers.

What type of guitar is yours? If a hand-crafted instrument, the builder may wish to know your feedback. If not (and if the monetary worth of the instrument is not terribly high) it may be best to learn to live with it.

You may find, however, that different total amounts of tension may strengthen or weaken the wolf tone.

[Troisnoir]

You may find, however, that different total amounts of tension may strengthen or weaken the wolf tone.

That really seems to be what I'm finding. That would account for the changes as I increase or decrease tension via string gauge, the pitch I tune to, and saddle height.

I have a Taylor Grand Symphony, (the rosewood/sitka model) which is pretty loud and bassy anyway, and then after tuning down to D standard, the overtones and richness just jumps out. Perhaps I'm pushing things to their limits. I don't remember any problems in this area when I first got the guitar (back when I tuned to E, using .013's).

Thanks for the help!

[Ned Milburn]

A good way to understand a guitar and its particular strong and weak resonances is to play each strings harmonics up to the triple octave and beyond. A good guitar should be able to pump out the G# (3 octaves above the fundamental) pretty easily on the low E. The differences between guitars often crop up when checking the 5th to string and through to the 1st. You will find that as the string pitch gets higher, the ability to get strong high harmonics (near the triple octave, about a third of the way from the 2nd to the 3rd fret) is lessened. But a well resonant guitar should be able to get the triple octave and above for the 6, 5, and 4 strings. The 3rd string and beyond is where things start to fade.

If you try this with different string changes and tunings, you may find the response change slightly.

[redir]

Have some one play the F note and find the part of the top that is vibrating the most and then stick a piece of Blu-Tack gum on it and see if that solves the problem. If it does then stick some gum on the inside of the guitar. Start off with very small amount and work your way up. You don't want to add any more then necessary.

[arie]

Originally Posted by redir

Have some one play the F note and find the part of the top that is vibrating the most and then stick a piece of Blu-Tack gum on it and see if that solves the problem. If it does then stick some gum on the inside of the guitar. Start off with very small amount and work your way up. You don't want to add any more then necessary.

have you talked with Taylor? wolf notes are a result of the build and are not your fault. they might have something to say about it -or not


as a wolf note is "a sustaining sympathetic artificial overtone" (isn't wikipedia great!) the goal is to change the resonant frequency of the top by either dampening that particular note, or adding mass, or taking mass away. i wouldn't recommend shaving wood or anything, but you can add mass easily to try to tune out the note. the ancient ones would use lumps of clay to try to dampen out a wolf note.

here's an attenuator on a cello:



these guys have rubber tubes inside that dampen the string. although on an acoustic guitar we just don't have that room behind the saddle, we do have that room behind the nut. and while it won't really do anything for fretted notes, it might help with the open ones.

[Alan Carruth]

arie wrote:
"as a wolf note is "a sustaining sympathetic artificial overtone"..."

Well, I would not put it that way.

Wolf notes are the result of strong interactions between resonant modes, whether of the string, the air or the wood. In the most likely case, when you get a strong resonance in the structure or the air that matches a note you're trying to play, you can get a wolf if the conditions are wrong. That's what happens on the 'cello. Wolf notes are more of a problem for 'cellists because the string is bowed: we tickle the wolf and walk away when we pluck a string, they tie it down and torture it. On the guitar the usual 'wolf' notes are caused by a strong resonance of the top or the air (or, more likely, the two working together, just to make things more complicated!) at a pitch you are trying to play. These often occur right around G on the low E string (~98 Hz) and the open G string pitch at ~196 Hz.

The lower one is the 'thuddy G', fabled in song and story. The top extracts the energy from the string and turns it into sound very quickly, so you have a note that's twice as loud for half a long. The one in the range of the open G string can do the same, and, of course, if you have both of those pitches matched on the same guitar G notes become really problematic. The exact pitch of both of these varies, of course, and your F is certainly within range.

Either of these can also cause the sound to 'warble', due to some tricky interactions with the string. If there's a 'tap tone' on the back as well that matches the upper resonance things can get really strange.

The first thing you need to do is determine what's causing the problem. This can be the hard part. One weapon that's really handy is poster adhesive: sticky clay-like stuff that's used to hang papers up and deface walls in college dorms. It's better than modeling clay in that clay has mineral oil in it, which can leach into wood. The object is to stick a wad of stuff onto an active area of the resonant mode, which drops the pitch due to the added mass. When you get the pitch out of range of the played note, the 'wolf' should go away.

Sometimes a good way to fix this sort of thing is to alter the low 'air' resonance that couples with the top and helps determine the pitches of the modes. You can do that by covering part of the sound hole.

Once you find an effective spot the thing is to see how little added mass or sound hole restriction you can use to just fix the problem. Then you can figure out how to get the same effect in the most elegant way. For example; if adding five or six grams of mass to the bridge works, you might try switching from plastic to bone bridge pins. If some mass placed over a brace on the inside of the box works, maybe shaving that brace down a little to reduce the stiffness will have the same effect.

One caveat: wolves can come and go. Despite what Bob Taylor says, guitars _do_ 'play in', and sometimes that makes enough of a difference to eliminate a wolf. Even changes in humidity can alter wolf tones, which can make finding them frustrating! When all else fails, a heavier bridge might just do the trick by itself. You'll lose some power, and gain some sustain, and that might not be what you're after, but nobody likes a wolf, and it might just be worth it.

[redir]

Originally Posted by arie

have you talked with Taylor? wolf notes are a result of the build and are not your fault. they might have something to say about it -or not
.

I'm not really sure what you mean? Does Taylor have an article on Wolf notes that I might have missed?

[arie]

i have no idea about whether taylor has any articles on wolf notes. my point was (for the OP) to merely ask them their opinion (it doesn't hurt to ask right?) regarding returning the guitar, possible fixes, etc... seems like a possible first step.

[redir]

Originally Posted by arie

i have no idea about whether taylor has any articles on wolf notes. my point was (for the OP) to merely ask them their opinion (it doesn't hurt to ask right?) regarding returning the guitar, possible fixes, etc... seems like a possible first step.

Oh I see so you meant to quote the OP

[arie]

sorry for the confusion. i meant to address your tack gum method. i think it would work pretty good -far better then clay.

[Troisnoir]

Thank you all for all the input - very helpful.

I believe part of my problem may be that I'm tuning down. The guitar may not have been designed for that.

Some problems troubleshooting my guitar may be, as noted above, changes in humidity.

I tried changing to a significantly higher saddle, and tuning up to Eb to stiffen the strings. Not only did it alter the wolftones somewhat, it changed the tone of the strings noticeably. We'll see if this works/lasts.

I will definitely try the sticky stuff technique if this doesn't go away.

Full disclosure: in addition to tuning down, I also have a bone nut and saddle, bone pins, and jumbo frets. I've modified this guitar fairly much.

I think I'll still have a qualified luthier check the bracing for gaps/looseness, just to make sure.

Thank you all again for your input, I've learned a lot!

[aadvark]

They can definitely 'play in', on a new guitar... but I would for sure try going back up to concert pitch and going with lower tension strings instead.

Thanks for the other excellent comments in this thread!

If you think wolf tones are problematic, try working out Shepard tones! (Wikipedia will get you there).

[John Arnold]

On the dreads I build, I like for the top resonance (and the resultant air resonance) to be higher than an F. Between F and F# seems to work OK. Any more flexible, and the 'looseness' of the top tends to aggravate the wolf tones. As you have found, lower tunings will also tend to make it worse, since it reduces the string tension on the top.
With that in mind, instead of adding mass (which lowers the frequency), I would concentrate on increasing the stiffness. Adding height to the braces or adding more tall and thin braces is the way I would approach this.
You may also help it by replacing an ebony bridge with a lightweight rosewood one.

[aadvark]

Thanks John,

this is why we defer to the experts!