Tuning issue

[Phil Redman]

When I tune my bass using harmonics the open G string ends up being flat. Is this a setup issue?

Thanks,

Phil

[Jake deVilliers]

Relax on the couch and explain further.

Can you describe your tuning procedure and what you mean by flat? Flat as compared to what?

[robobass]

Tuning is not black and white. I was taught to tune pianissimo with the bow, and that plucking or letting the string ring free would allow the upper harmonics to go sharp. In practice, I find that the pitch produced from light bow pressure is slightly lower than if I bow at forte or pluck the string. This effect can be more pronounced on a stiffer string, like a Spiro, than on something softer, like a Helicore Orch. or an Obligato. Also, I find a more pronounced difference on a softer bass like my Pfretchner 4-string than on my very stiff Poellman 5-string. So, what to say... you have to adapt the way you tune to the way you play, the strings you use, and the characteristics of your bass. Setup is probably an issue, but a lesser one. Also, when tuning I try to always damp the strings that are not involved at the moment. Sympathetic vibrations will cloud the process!
Hope this helps.
Robobass

[CPike]

Originally Posted by Phil Redman

When I tune my bass using harmonics the open G string ends up being flat. Is this a setup issue?

It could be a bad string or a wolf tone (or a combination). Over time, strings can become "false" due to uneven stretching. After I put my extension on, a slight wolf tone appeared on my E tuning harmonic that was never there before. When I tune the open E or 1st partial, the tuning harmonic is unstable (wolf) and sounds very sharp. My workaround is to close the D capo, and match harmonics with my open D - then close the E capo and kinda "split the difference". Right after I put the extension on and this wolf appeared, I assumed it was a false string - because I had used an old one to fit the extension. But, when I put a new string on the wolf was still there.

My suggestion to you (if a new string doesn't solve the issue) would be to use the tuning harmonics to get close, then play a harmonic double stop G+D at the 1st partial, then another double stop - open G + 1st harmonic D - and try to find a happy medium. Keep in mind that any tuning method is a compromise at some level.

Chris

[Muusers]

it could be a setup problem yes

check if your string is octave-true
with a TUNER check if the harmonic above the 12th fret is the same as the 12th fret pressed, if it's not octave-true (so not the same reading from the tuner) you need to adjust the bridge setup a notch.
if it is octave-true, get new strings

D

[robobass]

Originally Posted by Muusers

it could be a setup problem yes

check if your string is octave-true
with a TUNER check if the harmonic above the 12th fret is the same as the 12th fret pressed, if it's not octave-true (so not the same reading from the tuner) you need to adjust the bridge setup a notch.
if it is octave-true, get new strings

D

I don't think this bass has frets, but thanks for the advice anyway
Robobass

[Phil Redman]

Thanks for the comments. I suppose I do need to be willing "split the difference" in this case. I'm pretty sure the strings are fine. The problem existed when I was using Velvet Animas but does seem a bit more pronounces now that I've moved to Spiros.

Cheers,

Phil

[Gearhead43]

On an instrument with a straight bridge, like a DB, it shouldn't be possible for each string to be "Octave-true" (his term, not mine) , like a guitar with movable saddles for each string.

One must adjust slightly with the ear/fingering to play in tune, right? - of course there's no such thing as perfect intonation on a fretless instrument, either.

I've never had this explained to me, to my satisfaction anyway.

Being new to the DB, I practice with a tuner clipped to my bridge to help train my ear.

[Andrew McGregor]

The bass has a pretty low string tension compared to the amount that can be added by the energy you put in the string vibration. So, as you play louder the string goes sharp, and you find yourself fingering further back to compensate (low F is particularly spectacular for this, it can move by whole centimetres depending on the volume).

Add to this that the effective length of the string depends on the harmonic (in such a way that the harmonics are always slightly flat), and you get an instrument that is fun to tune. Just come to an agreeable compromise, be rigorously consistent, and get used to playing it that way.

[Alex Scott]

just tune the g string again. Do you tune the E last and then the g is out of tune? It is because the tension of the neck changes with the other strings and they stretch the g string flat. It always happens to me too.