Strange "Chorus-ey" sound on upper frets?

[conebeckham]

I've got a Tune Zii3 that's my main axe, and I love it. I'm also not shy about basic set-up and truss rod tweaks. The bass has titanium-reinforcement in the neck, apparently, though I'm not sure how this works.

Anyway....I switched strings to DR Longnecks a while back, and changed string height, etc., and messed with the action a while back. I've got it set up now just the way I like the action--it's pretty low, but not super-low...

the only problem is, there's a strange "sibilance" playing above the 15th fret or so, on D string and all other lower strings....(Puh-leez, no jokes about "why are you playing up there anyway? )-
It's almost like a "chorus" sound....like two notes together, slightly out of tune, and sounds a bit "choked"-but the notes sound, and sustain.....

I've checked intonation at the 12th and 24th fret and all seems fine, actually.

Any idea what might be going on here? I was thinking maybe resonance of the neck reinforcement? Or is it something else?

[Jim Nazium]

My guess would be it's the strings. DR strings don't have the silk wrapping at the end, and if you look in the package they have instructions for bending the string before cutting it so the windings won't come loose. They also recommend that you use a peg winder and don't wrap the string around the post when installing it. If the wrap wire comes a little loose, it will cause that "chorus" effect you're describing. Been there, done that.

[moles]

Have you checked to see whether its the string length below the fretted note sounding out? Just to clarify - if you're holding down a note on the 15th (F on the D string), then the string from the nut to the 14th fret may be ringing slightly - depending on the amount of neck bow that you've now dialed in during your setup.

[mikezimmerman]

One other possibility that I've seen is that the pickups are too close to the strings. The magnetic pull can also have that effect. Try lowering the pickups.

Lastly, I've also experienced this problem many times when trying taperwound strings on a bass that was not originally set up with them. In most cases, I had to go back to non-tapered strings. My suspicion is that if the taper extends too far past the saddle, it creates some weird overtones, but I can't be sure.

Mike

[bassybill]

No, not likely to be an issue with the neck. It sounds like a textbook case of "stratitis" to me. The clues here are the fact that you've lowered he action, it's only noticeable when fretting high up and it also affects heavier strings more. It's caused by the pickup magnets actually pulling too strongly on the strings as they vibrate and affecting the frequencies produced.

A quick google for stratitis will get you suggestions for setting up to avoid this.

EDIT Mike beat me to it.

[Steve Bennett]

Make sure you have a good witness point where the string breaks over the bridge saddle. Push down on the string to make a nice clean angle, not a hump.

[elgecko]

Yup, sounds like the strings are too close to the pickups causing the magnets to deflect the strings, resulting in an audible "waver"

[kalle74]

DR Long Necks are designed for basses with long scales (35 and up), AND for thru-body-stringing. I don´t know about Tunes that much, but if your string´s tapered portion is over the pickup, that will cause the problems.

[conebeckham]

Thanks folks! Sounds interesting, and I will do some more research based on your suggestions. Maybe I'll try stringing with non-tapered strings. First I'll lower the pups though, to see if that's the scoop.

[conebeckham]

..oh, and thanks Kalle74 for the pointers on Longnecks. I didn't know they were specifically for long necks....my Tune is a 34" scale, with regular bridge to peg stringing...no through-body option.

[Andrew Jones]

+1 on P.U's are too close to the strings.



Aj