Switching from rounds to flats -- what should I do?

I've read that when you switch from roundwound strings to flatwounds, you will have to adjust the truss rod regardless of the strings' gauges. How should I change my setup once I put the strings on? Is it safe to string flats through the body? The strings in question are Lakland Joe Osborn flats. Thanks a lot!

[Trevorus]

I generally don't string through the body with flats, ad it will increase the break angle, and expose the shar edges of the windings. This could hurt if you play near the bridge. Also, you could do a good setup on it, which is always good when you change string type. Definitely do an intanation adjustment.

[jetsetvet]

Really you shouldn't change any adjustments on your bass when switching strings until you have actually switched the strings. I have never played Joe Osborn flats but I have heard that they are fairly low in tension by comparison with most flatwounds. I have a bass strung with Thomastik flats and they are the lowest tension strings I have ever played.

In most cases when switching from rounds to a similar gage set of flats, tension will increase, and a tightening of the truss rod will be needed to maintain the same amount of relief in the neck as before. But when first using the Thomastiks, I actually had to loosen the truss rod, in order to maintain a bit of relief. So, I would not advise you to adjust your truss rod first, unless you are certain that the tension of the new strings will be significantly greater or lesser than it is now.

I would also think that, as with the truss rod, you cannot really make pre-emptive saddle adjustments for string height and intonation, before actually stringing up with the new strings.

It's interesting too that different makes of strings of similar gages can significantly vary in tension, and resulting feel. I recently tried a set of Ken Smith Burner Nickle-Plated rounds in 40-100 that I had thought might be lower in tension than I am used to with 45-105 D'Addarios, but the tension stayed about the same, as did the neck relief. Surprisingly nice strings, these Smiths. I never would have tried them, had I not seen a new set for sale at a garage sale....$5....great grab. Good deal at the regular price too......

http://www.juststrings.com/ksb-aa-bbl.html

Also, as far as using flatwounds on a bass with a string-through-body bridge, I would say to go for it. I own a Travis Bean bass that is a string-through bridge and have had Ernie Ball and LaBella flats on it with no problems.....oddly enough, I have never broken a string of any kind on this bass.

Thanks for the advice, guys. I wasn't going to set the bass up before changing strings; I just didn't know what to expect. I'm sure the Joe Osborn with flats will sounds great.

[SGT. Pepper]

Those strings are pretty low tension for flats. You may not need to do anything adjustment wise.

Cool. Are they still higher tension than most roundwound strings? I was hoping that switching to flats would give me greater tension but it looks like I might have picked the wrong string.