Parallel Capacitors-Theoretical Question


I want to replace the capacitors in my speaker's crossover networks. My Large Advent's came stock with 13uf NPE's which I would like to replace with PIO caps. Unfortunately, PIO caps are unavailable in that value. What's the best way to get to 13uf, (12uf + 1uf) or (6uf + 7uf)?
This is a purely theoretical question and I realize either method would probably sound the same, but I'm wondering if there is a reason why one method would be preferred over the other. Are there phase, impedance or other issues associated with either method. I realize of course that I could simply use 12uf or 15uf and probably never notice anything given that the original 13uf NPE had a 20% tolerance, but in theory, what's the best way and why?
heyraz

Showing 5 responses by jburidan

I believe it's better to go with 6uF + 7uF.
Some cap makers have 6.2uF & 6.8uF values, e.g., ClarityCap MR (630V).
Since the engineers at Advent used a single 13uF cap, my guess is that they didn't want the high order harmonics. Using 6.2uF & 6.8uF would alter the harmonic structure somewhat; and using 12uF & 1uF would alter it more. I guess the choice would depend on what kind of tweeter is in the Advent, e.g., silk dome or metal.
I gather that the results of adding bypass caps are unpredictable. Some reviewers (Auw Jimmy, Jon L. & Tony Gee) make the analogy of usng spices in cooking. They experiment until they hit upon a sound flavor they like.
Kirkus, please elaborate on the statement that 6uF & 7uF caps together will be better than one 13uF. Isn't there a benefit to having two less solder joints in the filter?
Thanks,
Jay