Great question, i once had heavier gauge strings on this year's ago. I have replaced the nut since then though. This bass is really a beater to be honest.. Sounds and feels great but I'm definitely willing to do some work on it if needed.
Tapes aren't for me honestly. Id prefer a roundwound but i would consider trying out flats on this though. I've never seen acoustic flats before.
A possibly unnecessary note but here goes anyway: you don't have to have "acoustic" strings on an acoustic bass guitar. Not mandatory for tone, much less for structural reasons (the top/bracing and neck only care about tension, not winding material).
The above being said, if as I suspect "acoustic flat" = bronze flat, here is an exhaustive (in all senses) writeup on what the bass string market currently offers as far as bronze strings:
-bronze roundwounds
-coated bronze roundwounds
-Elixir Nanoweb Coated Acoustic Bass (80/20 bronze; unlike competitors, they coat the finished string instead of the windings, so they're a bit smoother to the touch)
-(processed rounds) GHS Pressurewound Bronze, available in a sole 4-string long-scale set, the 4L-RBB, and a separate low B, RBB120
-(clear nylon tapewounds) La Bella 760G and 750G Gold White Nylon Tape Wound ("gold" being actually Golden Alloy i.e. 80/20 brass/bronze; they also make Copper White Nylon sets, the 760C and 750C)
-(black nylon tapewounds) Warwick Black Nylon Tapewound Bronze (
4-string sets plus
single B)
-(flatwounds proper) 760FGS Deep Talkin’ Bass Gold Flats.
Regarding how acousticky they sound, if at all, when installed on an ABG: I seem to remember, in a nutshell, that one does not find them to be especially better-projecting or -sounding than steel or nickel flats, unlike what happens with roundwounds of the same materials. They are flatwounds, and of the thumpy sort, which seems to matter more than the flat ribbon being bronze.
[Paging @Karl Kaminski to either confirm or correct what I remember having read about Deep Talkin' Golds on ABG.]
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All the above having verbosely been said,
On my 32" scale I use and love the
Savarez 4CB640R set. They're nyloncore roundwounds, like the Thomastik-Infeld Acousticores, only
- silverplated copper instead of phosphor bronze
- higher-gauged, for a more familiar feel, or a less odd one I guess
- a lot less expensive.
In fact, they're so inexpensive I believe any ABG player should try them just to get an idea how nyloncores sound and feel. However closely or not they compare to the T-Is, they may just be a temporary detour from them, or could serve as a gateway to them.
A 34" version exists, called 4CB640RL.
[A caveat: they come with no ball-end, so they need their (nylon, hence fairly pliable) plain ends to be tied into knots, or to old ball-ends.]