Acoustic Bass Problem

Congrats on getting an acoustic bass. They're great. I'll have to get one one day.

Anyhow, it might be something as simple as the strings being old. When they stay on a guitar or bass for awhile - like when the bass is sitting in the store or its packing box, the strings can stretch out and become 'false;' meaning they the material of the string is no longer 'even' along its full length. There's sections that maybe develop over time where the metals more stretched out and some places where it's less stretched. It gets uneven that way and can make the string be off at the 12th fret.

You might try getting a fresh set and putting them on.

If you've already done that, then the saddle where the strings go over the bridge may be slightly out of adjustment. If it's adjustable then you can do it (or someone else might) by turning the screws and moving the litttle pieces. Most acoustic basses don't have adjustable saddles like that so it might have to be done by a guitar technician.

It might just be the strings though.

Take care.

It sounds like the intonation is out to check this play the E string open and fret the A on the second seventh and fourteenth frets they all should be the same note if not it is out if intonation. The idea of changing strings is a good one. You can also look at the bridge to see if it is lifting from the body see if the saddle is sitting square in the bridge. You said nothing about buzz so your neck is more then likely fine, but if the action is real high the neck angle could be off. To see if this is the problem look at the butt of the bass where the neck meets the body of the bass and see if there looks like there is and space there if so you will need a neck set done I do not know where you live but go to a good music store in the area, one you know the professional musician go to and ask if they know a good guitar tech someone will let you know who to go see. Good luck and I hope you get it fixed there is nothing that will annoy you more then having an axe that will not go in tune

Intonation changes with different string gauges on a bass more than on a 6-string guitar. See if you can determine if the strings installed are the recommended size.

Laz