Quick demo of parallel vs. series wiring on a Duncan Hot Rails Strat bridge pickup. I recorded my Strat “Rosie” below direct into the computer. The Hot Rails bridge is wired series/parallel on the “tone” pot (actually a variable split pot).

THESE ARE NOT MEANT TO BE GREAT TONES JUST A COMPARISON. I played some snippets of an old Trapeze song, there are 4 snippets on the track. Parallel first, Series 2nd, Parallel again 3rd, Series 4th. I added a little doubler/slap effect to try and make it sound less crappy, the ONLY thing that changes during the clip is parallel/series. I’ve posted the same clip twice, direct and with a simulated “amp”.

This first clip is the guitar direct (no EQ) with some slight compression to smooth out the level (series is quite a bit hotter in output).  Recorded direct the tonal difference is pretty dramatic. Parallel first and then it alternates.
Direct only:

Next I used the same clip but added a basic guitar amp plugin to simulate what an amp does. Notice the difference is not so dramatic, the crunch of the “amp” helps the series tone be less muddy. Parallel first and then it alternates.
Amp plugin added: