are you talking about the black nylon tapewound strings? i have a set on a jazz bass (fretless) and i like them. they do sound warmer than steel strings, but they aren't as bold/defined either. i have no problems with volume, though i'll admit they aren't loud strings. the ones i have are fenders, mostly because they were cheap (25$), but they sound nice enough. worth a shot if you're keen to try tapewounds.
Matt