What makes them different. Can I use either.
- Bronze (or copper) roundwounds are louder than anything else acoustically, but don't work so well on electric (magnetic-pickupped) instruments (only the steel core can be sensed by the pickups because bronze, used for the windings, is non-magnetic, as is pure copper);
"electric" strings (nickel- or steel-wound - the above-mentioned GHS PW Bronze are included, because only the outermost wrap is bronze, whereas the intermediate layers and core are steel) are less loud acoustically (not per se, but because copper or bronze have been proven to be the loudest);
- yes you can use either, because acoustic bass guitars have, well, hollow bodies, duh, and (not-so-duh) piezo pickups, which sense pressure (ferromagnetic content or lack thereof being irrelevant).
For example, the above-mentioned Thomastik-Infeld AB344 set - but also other similar, less expensive sets - have no steel nor nickel (core is nylon, wrap is bronze) but work great with piezos.
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Point #2 (use whatever you want)* having been established,
popular and strongly argued-for choices for ABGs are:
- bronze rounds (as comes stock) for a bright, downtuned-acoustic guitar tone; if you can find them, Elixir Nanoweb coated bass bronze strings are a little smoother than normal uncoated rounds
- nylon tapewounds (lower acoustic volume but a double-bassy tone)
People also use:
- their favourite "electric" rounds or, for less finger noise, processed rounds (pressurewounds, groundwounds aka semi-flats)
- flatwounds (similar to nylon tapes in that these are relatively quiet but reminiscent of upright bass in tone and feel)
- nyloncore rounds.
I've been using Savarez silverplated-copper nyloncores for some years, but am looking to try a new, nyloncore flatwound set by Galli.
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* [whatever you want, but within reason:
- very stiff strings would require some finagling of setup - a tighter truss-rod for a straighter neck, a lower bridge saddle - to achieve correct intonation (if at all possible);
- heavy-tension strings (which tend to also be stiff, see above) may cause behind-bridge top-bellying, bridge-lifting, or both.]
