B&W 803D crossover caps

Ptss:
Sorry if I misinterpreted your comments. Mine were based on an experience I had a few years back with B&W regarding a delamination problem I had with some 804s speakers I had. The finish on the top of the speaker (Cherry) was splitting and cracking and I felt this was a manufacturing defect but B&W would not agree. They were arrogant and condescending which left a bad taste in my mouth. They also tend to believe that their engineers have the last word in innovation and if they did not think of it, well then it will not be an improvement. Ergo I would be loath to contact them about any potential component replacement as I can pretty much predict their response.

You mention JBL and I was going to point out that I also re-built the crossovers in my JBL L212's, as well as the power amp in the sub. I did not use crazy audiophile components (just good Dayton polypro caps and air core inductors) and the sonic results were amazing. I had previously modded these by mounting the drivers on solid walnut plates to time align them. That mod is documented on the JBL Lansing Heritage site (under DHL or DHL93449 no sure which) a few years back.

http://www.audioheritage.org/vbulletin/showthread.php?32862-Modded-and-restored-JBL-L212-speaker-system

http://www.audioheritage.org/vbulletin/showthread.php?33993-L212-Sub-amp-rebuild

The post on the WB forum is under the Spectral Manufacturer's section of the forum.

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

DHL,

I wanted to thank you as well for your thoughtful reply. I will be interested to learn how your project goes and hope that you will post updates to this thread.

I wanted to make one more comment about the capacitors I discussed which were in a bit of disagreement with Tony Gee's observation. For me the Mundorf S/G/O tilted things upward too much whereas I found the Clarity MR to be very well balanced. In my system the latter was the superior performer and based on that experience I would not recommend the former to anyone wanting to avoid adding emphasis to the high frequencies. Face's and/or Undertow's comments on this topic a few years back on the Capacitor Log thread make for good reading as well. I agree with you too that it'll ultimately come down to system synergies and personal preferences, I simply wanted to relate my experience for your consideration.

All the best,

John

John:

The more I look into this and the more reviews I read, the more opinions differ.

Looks like the 47 mFd will probably be the Mondorf EVO. Al/oil or SGO I am not sure yet. Some say (ie Tony Gee) that the Al oil are better for midrange which is the application here. On a purely material basis, I prefer the use of silver metallization over Al due to it's conductivity. No one else makes a cap this size that even comes close to fitting.

For the Diamond tweeter coupling cap, I could use the Clarity MR, as it is very reasonably priced. I cannot find anyone with stock on the 630V part, only the 400V part, which Parts Connexion carries. Do you know of any stocking dealers for these? Any opinion about 630V vs 400V? I have heard one should use the highest voltage rating is a series (Tony Gee again).

I would also consider the Jupiter for this application if it weren't for the very high cost of these ($520 pair). If I don't like them, I may not be able to re-sell them if they have been soldered in a circuit. I was speaking with (Jerry??) at Jupiter and he was very knowledgeable, but had no direct experience of the copper foil/wax units being used with B&W diamond tweeters. He also made mention that a source he knows (that likes to cut apart caps to see what's in them) tells him Mundorf "oils" actually have no oil in them. I find this surprising, but perhaps they use extremely small oil films that are not easily detected.

Dhl: I have a bit of recent experience, although with a different speaker. This summer I threw caution to the wind and did some nice crossover upgrades to my Tyler Woodmere speakers. I wanted to share my results in a dedicated thread, but I wanted to give you my thoughts now, so that you could have a bit more information to help you.

I swapped out the SEAS Millennium tweeters for the new SEAS Beryllium tweeters (exact size and fastener swap). I already had the Mundorf Silver/Gold/Oil tweeter cap. I am very, very pleased with the result. I did, naturally, swap resistors also, to match sensitivity as required. I won't go into a long rant, but this is super nice now. Multiple high freq instruments now are played simultaneously with realistic separation and space of each. Nothing harsh or tinny. And the presence is superb.

The tweeter mod was so nice, it made me long for better-defined midrange, especially upper mids where they are approaching high frequencies, as the mids did not measure up to these great high freq notes. Midrange caps are 120 uF, and I bit the bullet and bought six Mundorf M-Cap Supremes which total that capacitance. Yep, they are a big bunch of caps that take a lot of space. Well....was it worth it?? Hell Yes! A good bit of break-in was required, and right off the bat I only noticed more separation in upper mids. But as they broke in, I am getting a ton more definition, air and bass. Much more lower midrange/upper bass coming through now. The midrange drivers are 7", and in the big Woodmere enclosure I get gobs of bass. That is the biggest adjustment for me. I keep asking myself- is it realistic, or just bigger? Those big midrange caps are nearly broken in now I reckon, and I think it is both bigger and more realistic. I accomplished exactly what I was hoping to do in keeping up with the new tweeters.

Best part is that these improvements, while significant, do not ruin the overall sonics of the Woodmere speakers. They have simply been woken up. I could not be happier. Hope this gives you a bit of confidence to try your luck.

DHL,

It's funny how these reviews go. I think at this level of capacitor it must come down to system synergy and personal preference.

I have experience only with the 630VDC version of the MR and that's the one with which I would stay. For my friend's crossover project a few weeks ago I ordered a set of MR's from PartsConnexion. They didn't have the ones we needed in stock but it only took them a couple of days to get them from their distributor. If PartsConnexion is indicating a longer delay for the values you need then you might give MadiSound a call. HifiCollective in the UK might be another source.

You mentioned the various conductive materials in your post. As I know you are aware, the MR is an aluminized polypropylene cap. I prefer the tone of the copper film caps more, but as you also mentioned in your note the cost of admission to those caps is high. To me, short of making the jump into those caps, the MR is the best out there.

I reread your original post and it looks like you need a 4.7mfd for your tweeter? I have a pair of MR 630VDC in that value that I don't use anymore since moving the crossover to Duelund CAST. I'll send you an email offline to discuss further.

Cheers,

John