B&W 803D crossover caps


I am considering an upgrade of the crossover capacitors in by B&W 803Ds, particularly the mid and HF coupling caps.

I took out the top bass driver to find out what caps were installed. It looks like for the diamond tweeter B&W uses a Mundorf Supreme silver/gold, 4.7 mfd 1200V. For the mid driver there are two; a 47 mfd Mundorf MKP 400V series coupling cap (in series with the driver) and a 10 mfd Mundorf Supreme siver/gold bypassing cap (parallel to the driver).

I was thinking about changing out all three, but have a few concerns.

I was going to replace the 10 mfd, 4.7 mfd Supreme silver/gold with Supreme silver/gold/oil. Would there be enough of a difference in these two types to justify the cost? I also do not want to make the upper end any brighter.

I am also concerned about the long term reliability of oil filled caps, as some failures have been reported in warmer environments. I wonder if B&W did not use the silver/gold/oils for that reason.

The biggest impact I suspect will come from the replacement of that series 47 mfd MKP. I would probably use either the Mundorf MCap EVO (Al metalization), MCap EVO oil (Al/oil), or the MCap EVO silver/gold/oil. All three are the same size for 47 mfd, and will fit to replace the MKP. Barring the issues about oil, which might be the best sounding? Again, I want to avoid too much enhancement of the upper midrange.
dhl93449
John:

I wanted to thank you publicly for generous offer. I will try those Carity caps when I get them.
Thanks DH for the link. I found it interesting but did not see any post mods pics?
Dhl: My project was really different than yours, and it is not a direct comparison at all. Sorry if I failed to make that clear.

Tweeter upgrade was only drivers. I had already started with the S/G/O, so my only variable was the driver.

Midrange upgrade was only capacitors. I originally had a single Solen cap and replaced it with six Mundorf M-Cap Supremes. No further comparison. I went about as far as I could go, given the large cap values of the mids. I think that set me back about $900.

Sorry I have no direct comparisons between other caps.
Giving it another try to help here, after re-reading your scenario. For my project, I read all the cap shootout opinions and took my chances. My beryllium tweeters really like the SGO, but I cannot say more. Absoutely zero objections.

For the mids, I read in more than one cap comparison report that M-Cap Supremes shine in the midrange. After a lengthy break-in, I can agree, although I hear more lower-mid pronouncement than upper-mid (in my rig and in my room- an extremely important qualification that cannot be ignored). I also seem to recall reading that M-Cap Supremes, in crossover applications, yield a better result than EVO, which led me to the M-Cap Supremes for my midrange caps. For about $200 per speaker, you can try two 18uF plus one 10uF, which will yield nearly your 47uF target. To me, it makes sense to try that one first. Took about 20 hours to sound decent, and 50 hours to sound good. After that, they just kept getting better, with more sound and detail coming through. But that was compared to the Solen cap.

Good luck, and please keep us posted.
Ptss:

If you are referring to the Spectral posts, there are three parts because WB forum had a limit on photos per post.

Here are links to all three parts:

http://www.whatsbestforum.com/showthread.php?18147-Spectral-DMC-10-mods

http://www.whatsbestforum.com/showthread.php?18148-Spectral-DMC-10-mods-part-2

http://www.whatsbestforum.com/showthread.php?18149-Spectral-DMC-10-mods-part-3