Acoustic Bass string comparison?

[RustyAxe]

I have a 4-string, fretted Tacoma Thunderchief strung with the OEM strings (I think, bought it used). Those would be Elixers, same as D'Addario EPBB170 PB strings. I'm going to replace them with Thomastik-Infeld AB344 Acousticore strings. I know the TI strings are lighter gauge than the PB's. What I'm comparing is string tension, and whether I can expect to have to tweak the bass for the newer strings.

It's interesting to me that the lighter gauge TI's have consistently higher tension! Does that make sense? Can one determine the total string tension on the neck as simply being the sum of individual strings? If so, then the TI's will exert 23 more pounds of tension than the PB's. I thought TI's were less tension than other steel core strings. Any comments from those more knowledgeable than me? Thanks!

D'Addario specs

E - .100 - 18.23
A - .80 - 21.5
D - .65 - 25.26
G - .45 - 21.54


TI specs

E - .86 - 26.5
A - .68 - 27.3
D - .53 - 29.2
G - .41 - 26.5

[Parabolic Box]

You have kilograms (D'Addario) mixed up with pounds (TI).

[Darkstrike]

Acoustic Bass 4-string set Round Wound

Set: AB344 medium light | Set No.: AB344
----------------------------------------------------------ins- mm- lbs-- kp
AB34041 G 1st Phosphorbronze Round Wound on Nyloncore .041 1.05 26.5 12.00
AB34053 D 2nd Phosphorbronze Round Wound on Nyloncore .053 1.35 29.2 13.25
AB34068 A 3rd Phosphorbronze Round Wound on Nyloncore .068 1.73 27.3 12.40
AB34086 E 4th Phosphorbronze Round Wound on Nyloncore .086 2.18 26.5 12.00

Very strange.
By all accounts they are lower tension. But the numbers say different.


EDIT: Or what Parabolic said.

[RustyAxe]

Originally Posted by Parabolic Box

You have kilograms (D'Addario) mixed up with pounds (TI).

That might be ... I'll double check (can I get a job with NASA?). If so, then the PB's are

E - 40.1 lbs
A - 47.3
D - 55.4
G - 47.3

Total TI = 109.5
Total PB = 210.0

TI's exert HALF the tension of PB's? That doesn't sound quite right, either, though.

[Parabolic Box]

The TI's have nylon cores.

And, yes, you, too, can cause a crash multi-million dollar space probe to crash!

[Darkstrike]

The TI's are 109.5 not 86.5

[Darkstrike]

And the D'Addario's are 190.8.


Thats some bit closer.

[RustyAxe]

Originally Posted by Darkstrike

The TI's are 109.5 not 86.5

Yes, of course! I can't even read my own scribbles on the notepad, and picked up the wrong numbers. I didn't party last night, honest!

Thanks for pointing that out.

[Darkstrike]

No bother dude.