Why "Wobbly" Notes?

[Eyesee7]

Any idea what causes this effect? I have an early 80's Ibanez Musician "bean" bass. The F note at the third fret of the D string "wobbles" in certain situations. The same note played at the 8th fret on the A string does it also.

If I play this note as a single note by itself, it doesn't wobble. However, if I first play the E note and hammer onto the F, it wobbles. If I play a run of lower notes up to and ending with the F, it wobbles. If I play a run of higher notes down to and ending with the F, it doesn't wobble.

The intonation at the 12th fret on all 4 strings checks out.

 

[FretlessMainly]

"Wobbly" is too ambiguous a term. Does that mean::

1. the pitch changes?
2. the tone changes?
3. the volume changes?
4. a buzz comes and goes?

Y'know, we'd like to help, but...

 

[Eyesee7]

Yes, I should have been more descriptive. Have you ever tuned two adjoining strings using harmonics? When the two strings are in tune they vibrate harmoniously together. When you move one string sharp or flat, there is this discordant "wobble" or vibration. It kind of sounds like that. It's hard to describe.

It's not really a change in pitch, volume or tone. It's like the difference between a string vibrating evenly as the note decays versus a note decaying unevenly. Damn, it's hard to describe. But it's noticeable. It sounds like a sour note, but not an out-of-tune sour note.

And I'm not doing any sort of vibrato on the note either.

 

[Stick_Player]

Yes, I should have been more descriptive. Have you ever tuned two adjoining strings using harmonics? When the two strings are in tune they vibrate harmoniously together. When you move one string sharp or flat, there is this discordant "wobble" or vibration. It kind of sounds like that. It's hard to describe.

It's not really a change in pitch, volume or tone. It's like the difference between a string vibrating evenly as the note decays versus a note decaying unevenly. Damn, it's hard to describe. But it's noticeable. It sounds like a sour note, but not an out-of-tune sour note.

And I'm not doing any sort of vibrato on the note either.

The "correct" term is beats.

When you play the "F" (on the D or A-String), is your low E-string also vibrating? Make sure ALL the strings you are not wanting to sound are muted.

 

[Eyesee7]

The "correct" term is beats.

When you play the "F" (on the D or A-String), is your low E-string also vibrating? Make sure ALL the strings you are not wanting to sound are muted.

Thanks, I'll check to see if that's what's causing it. Sounds like a possibility.

 

[sammyp]

funky room acoustics? do you play this bass in a variety of rooms with the same effect?

 

[miiitch]

sometimes that happens to me as well, from 12th-24th fret on the F string.

reason in my case: technique (not pressing down the string correctly)

 

[JimmyM]

Pickups too close to the strings might be a cause.

 

[J Posega]

Sounds almost like you aren't muting all the rest of the strings, and you're nearly setting off the E harmonic on your other strings.

 

[4dog]

Mebbee sympathetic overtones,,,mebbee

 

[RedMoses]

sounds to me like

A. the intonation of your bass is off (provided you are in tune)
or
B. You have some uneven frets

 

[Russell L]

I bet it's the thing about another string vibrating. You said it doesn't do it under some circumstances, so I bet that's the cause. Heck, I guarantee it.

 

[Anonymatt]

Could be what they call a "wolf tone". Maybe you could search for some stuff on that. Has to do w/ the frequency of the note itself and the geometry of all the resonating stuff happening on the instrument. The wikipedia entry is neat. Just like it says, I've got one at G# on my upright. I forget where they are on my electrics. I think most people just get on with their lives and stop hearing it so much. You don't get it descending? Maybe it has to do w/ stopping the note either right on the fret or behind?? Fun stuff, don't let it kill you.

Cayce, SC in the house! I lived there while flunking out of USC.