Wolf Tone Anecdotes And Fixes

[mot]

I have a wolf on my favorite guitar. It's on the open B. It's not very noticeable when I strum, but when I play single notes it's sometimes annoyingly obvious to me. I try to avoid the first four or five frets of the B string because that's where it is the worst.

I have some pieces I am working on where I really can't ignore it anymore. The current string set up is Elixir nanos 12-53.

What are some ideas you know to help mitigate a wolf in the strings? Any great wolf stories?

I come from a fiddle background too, so I have tried small adjustments here and there and am considering trying different strings too. Curious about your thoughts before I go somewhere that may make a permanent change to the guitar.

TIA.

[Osage]

This can take a while but it's what I do for customers if all other normal things like strings don't work. I learned it from a well known classical builder.

Have a friend play the wolf note. Take you finger and move it around the top of the guitar, pressing firmly. This can take a while but at some point, you will usually find a spot where the wolf note either goes away completely or is greatly reduced. Mark this spot on the top so you know where it is. Take a piece of modeling clay or something similar about the size of the tip of your finger and stick it to the top in this spot. Play the guitar and see if the wolf note is still tamed and if everything else is still sounding good. If it is, Glue a small wooden cleat about the same size as the piece of clay to the inside of the top in the exact spot where you had your modeling clay. Once it dries, you should be in business.

[Osage]

Or just bring it to a luthier.

[Alan Carruth]

'Wolf' notes are generally tied to resonances of the air or the structure. These are normally pretty restricted in range, so it's hard to see how a problem that shows up over four or five semitones is a 'wolf' in that sense. There is a type of wolf that's intrinsic to plucked or struck strings (but not bowed ones) that can show up on every note of the string, or over a wide range of notes. It should clear up if you tune the string up or down a little bit: say a half semitone or maybe even less.

If the problem really is mainly on that open B, you could try loading the top or the bridge with a lump of poster adhesive to see if it changes it. This sort of thing can be hard to track down even when you have it on the bench; via e-mail it's a matter of luck, since there are a lot of possibilities.

[mot]

Originally Posted by Alan Carruth

'Wolf' notes are generally tied to resonances of the air or the structure. These are normally pretty restricted in range, so it's hard to see how a problem that shows up over four or five semitones is a 'wolf' in that sense.

It's most notable on the open B and still there though not as evident on the fretted C of the first fret. I don't notice it at all when I strum an open Cmajor7 or E chord. I usually just avoid the first several frets when I am playing single note tunes. Otherwise I will stop thinking about it and play the open B instead of the much more pleasant sounding B on the G or D strings.

I'll try poking around to see if I can find the where the wolf can be tamed. I'm thinking strings might make a difference too. It doesn't have to be mitigated much.

[BlueStarfish]

If it really is a wolf tone (as opposed to fret buzz or a binding nut or some other issue), and it’s on the open B (B3, ~247 hz) then it most probably means that the guitar top has a natural resonant frequency close to 247 hz. You mentioned C4 also has a somewhat lesser issue. So maybe the natural resonant frequency is somewhere between B3 and C4, a little closer to B3? Tough to say for sure. Could be something else entirely, you’ll have to tinker a bit.

Fortunately, it’s cheap to experiment with some ideas to see if you can tame it a bit. Here are three cheap ideas that helped me a lot with a guitar I’ve got with a wolf tone at G#3 (208 hz).

Idea 1: If you mainly play plugged in, set your notch filter on your preamp or amp to 247 hz. This obviously won’t help playing unplugged, but should help playing amplified.

Idea 2: Swap out your bridge pins for some brass ones (which are heavy and add mass to the soundboard, potentially bringing the resonant frequency down a bit).

Idea 3: Take a look at the following website: https://krentzstringworks.com/

The website is selling a wolf tone eliminator device for cellists, which they call a “modulator.” They want $150 for the device. You shouldn’t buy the device — you don’t need it. Cellists need something like that because they have f-holes, but flat top guitars have big round sound holes instead, you can stick your hand inside a guitar. So you can go buy $8 worth of coated rare-earth magnets at Home Depot or on Amazon, and apply the same basic technique shown on the how-to video on the website. Put one magnet on the outside of the soundboard, on on the inside, and move it around a bit until you find the sweet spot that most tames the wolf. Once you’ve found that spot, you can either just leave the magnets in place, or if you don’t like the look, you can use some putty to fix the inside magnet in place (and then stick the outside magnet on the inside too, if you need that much extra mass).

[BlueStarfish]

One additional thought for you. If it is truly a wolf tone, it should manifest regardless of what string you play the B3 on. So you should hear it at least some if played on the 3rd string too. You mention that B3 sounds much better. This makes me suspect it’s not actually a wolf tone but some other issue.

[mot]

Originally Posted by BlueStarfish

One additional thought for you. If it is truly a wolf tone, it should manifest regardless of what string you play the B3 on. So you should hear it at least some if played on the 3rd string too. You mention that B3 sounds much better. This makes me suspect it’s not actually a wolf tone but some other issue.

It's not obviously manifesting on other strings. This is good information. Comments from a luthier about my violin years ago led me to think that a wolf could be unique and manifest itself on one string even though another string may vibrate at the same frequency. There were lots of other conversations about post positioning and bridge, but my take away that a wolf can also appear on other strings if it's the same note though usually it's weaker or perceptually nonexistent.

I going to have to investigate for a while. I have some of those kid magnets, so that won't be a problem to use to test.

Thanks much.

[Alan Carruth]

A customer of mine turned up a 'wolf' note on a guitar that he'd had for several years that really baffled us. It was at D, third fret on the B string, but no other D note had the problem. We spent several hours running down the usual suspects. Finally we ran a spectrum analysis of the plucked note, and saw that the 3d, 6th and 9th partials were 'split'; showing up as closely spaced double peaks. Sure enough, there was a top resonance at about 880 Hz that was very active at the spot where the B string crossed the saddle. The top was moving enough 'vertically' at this pitch that the string didn't 'see' the saddle as a stationary point in that plane. It 'thought' it was a bit longer or shorter than it should have been, and made a different pitch. In the 'horizontal' plane the saddle was a good stop, and the string made the 'correct' pitch when it was vibrating that way. Since you always get both types of motion in a normal pluck the string produced two pitches for that partial, and the difference between them sounded like a buzz. A couple of shavings off one of the tone bars fixed it by moving the stationary 'node' line closer to the B string crossing.

I got some humble pie for dessert. A student had a similar problem on one he'd made, but when we checked it out it was not the same thing. Anyway, wolf notes are pitch linked, but may or may not be string linked.

[mot]

I'll figure it out eventually. I put a flat wound 016 on it on a lark. That seemed to affect the wolf in a good way. I was worried a flat wound B would be too quiet compared to the rest. It blends in nicely and is plenty loud enough still. I might just leave it at that for a while.

Going to play with magnets next.

Thank you everyone for the help so far. Gives me more to ponder.

Also, I might have to take a jaunt over to NH sometime. I'll wait to the weather is a little better though.