Double Bass My bass goes sharp

[bassbuddy]

Oddest circumstance lately - gigged this weekend, and both nights everytime I checked my tuning I'd gone sharp. Huh? Flat, that I can understand, but not this.

Ideas?

 

[willroland]

Is it humid out? Do you have a fully carved bass? I know down here in the deep south, in the summertime it takes about a set before my bass settles down. It just sucks up the moisture and expands, going almost a quarter tone sharp. This year, its been so dry so I don't have that problem.

 

[Jazzdogg]

My current band often plays "winter" gigs outdoors at a seaside venue where it's not unusual to come back from a break and find my strings have constricted in the cold and gone sharp. The same thing has happened when I've been positioned in the path of an air conditioning duct indoors.

When we play outdoor gigs in the daytime, I will sometimes find my strings stretching and going flat if I'm forced to play in direct sunlight. I've also learned not to get close to gas-fired space-heaters when playing outdoors; warms hands, and bass, and strings...

Of course, there's always the possibility that one of your bandmates is fond of so-called practical jokes. I used to work with a keyboard player who would substitute inconspicuously broken drumsticks when the drummer wasn't looking - usually when he knew the drummer would need to make a quick switch from brushes to sticks mid-song. On more than one occasion, he de-tuned my bass just before we went on stage after a break

 

[bassbuddy]

Jazzdog, that's just mean!

It's a laminated bass, so I can't imagine there's a whole lot of movement going on. It is fairly humid, for whatever difference that makes. I'll tune up at the start of a set, and check my tuning toward the end of the set, and darn if it hasn't gone sharp again. Which is a real drag, because whatever intonation problems I have usually manifest themselves as playing sharp to begin with - ouch!

 

[Silversorcerer]

Jazzdog, that's just mean!

It's a laminated bass, so I can't imagine there's a whole lot of movement going on. It is fairly humid, for whatever difference that makes. I'll tune up at the start of a set, and check my tuning toward the end of the set, and darn if it hasn't gone sharp again. Which is a real drag, because whatever intonation problems I have usually manifest themselves as playing sharp to begin with - ouch!

I have the same experience when the weather is warm. I think the wood warms up and expands a lot more than the metal strings. But on my nylon string guitar, the strings go sharp as I am playing, but not the wound ones, just the plain nylons. So what are your strings made of??

 

[John Wentzien]

Check the nut-slots (and string-tree if you have one) and make sure the string isn't getting hung up in there. A little pencil lead in the slots might help lube it up a bit.

 

[bassbuddy]

Right now I'm using the Eurosonics; I'm not sure of their overall composition, but I believe they have enough metal in them to work with magnetic pickups, so that may be the explanation there. The nut and bridge slots are fine, but I probably should put a little graphite in there.

 

[Jazzdogg]

I played an outdoor gig on electric bass last night. As the weather cooled off, my strings began creeping sharper, requiring me to re-tune every set (FWIW, I'm playing Thomastik-Infeld jazz-flats).

My guitarist said he doesn't have that problem, and suggested I upgrade my tuners. However, I think the phenomenon may be related to the fact that bass strings have far more mass than guitar strings, making them more responsive to temperature changes.

Does this sound plausible, or do you think my tuning machines may be at fault?

 

[Marc Piane]

It is my understanding that faulty tuning machines will only cause the strings to go flat. The gears slip. If the bass is going sharp I'd suspect something else.

 

[Jake deVilliers]

Jazzdog, that's an obvious case of shrinkage!

Maybe your guitar player plays really skinny strings because my guitar strings sharpen as they get cold, just like bass strings.

 

[Jazzdogg]

Thank you, Fingers and Jake; it's nice to have a sounding board like TalkBass. Perhaps I'm not completely nucking futs after all!