If you want a bright tone for slapping, go with DR HI-BEAMS. These strings meet slap criteria and answer all your questions. Oh, and tape strings aren’t close to ideal for slapping.
But keep in mind that it’s actually the player that delivers the final tone, not necessarily the strings. For example, master slapper Victor Wooten uses DR Pure Blues on his bass, and he makes those nickel strings wail.
Lastly, DR strings aren’t expensive, so you could try these two options for yourself without breaking the bank.
Well best and brightest strings are the Optima gold.
40 is about the thinnest I’d use for my liking. Anything lighter takes more skills and control to make it sounds good.
Victor Wooten and Sunny T use super light gauge and as you can hear their tone. it’s highs high and lows low, of course much has to do with the quality of the basses they are using, not to mention that they are a bit better than us mortals.
I prefer the standard gauge for slapping. The thicker the gauge actually “feel” better because of the feed back. Slapping with super light gauge and get too excited you’d get terrible tone and the thin slapping tone, and the popping is twangy. Not till you dial it down and light touch then it will start to sing. So moral of the story is standard skills, standard gauge.