B&W 802 D2 Capacitors Worth Upgrading?

@bossybilbo I wrote a blog post which was inspired by this discussion I think you'd find interesting.

@bossybilbo 

I found the Stereophile review, which thankfully was not written by JA.  The last page has a great description of the sound the B&W has stock, vs. the Revel Ultimas, which are in fact quite neutral.

It's worth reading as a guide to understand how the sound could change for you.

@bossybilbo

I love these speakers and in a way they have become a part of our home decor as well as the hifi system.

Welp, it sounds like you love the look but not the sound.  That's fine!! But it won't sound at all the same. It will sound much more neutral and laid back. 

I want to suggest you take future discussions over to DIYaudio where you'll get a lot of input from builders. 

I think you are taking a better approach than a cap replacement.  I'm going to write this up in detail in my blog, but looking at the original driver measurements I immediately thought of a DSP solution as being much easier than a passive crossover.  The mid and tweeter need a lot of EQ and that's why the author has to add so many more parts.

Tips:

• Consider a Hypex 3 channel DSP powered plate amp, perhaps in a custom box.  They have more than enough power. 
• It may be best to measure the speaker on mid-range axis.
• Always fix driver issues before setting high/low pass filters
• If you really want to stick to a 2-way amp per speaker, a hybrid approach using a passive woofer to midrange crossover. The woofer is probably the best behaved of all the drivers so needs least amount of parts.

Absolutely @erik_squires. I love these speakers and in a way they have become a part of our home decor as well as the hifi system. As such if there's a way to improve the sound by say "50%" but at a reasonable cost (meaning less than 25% of a new speaker) then it seems worth trying!

I'm a computer engineer by trade - after some careful consideration I've decided that I am going to attempt a DIY active crossover 2/8 setup with some reasonably priced class D amps. This will be closer to my background and allow for quick prototyping iterations. I plan to keep the drivers as is and remove all wiring harnesses and crossovers outright and fabricating my own - this will allow for easy restoration to OEM condition if/when I choose. I don't mean to derail the discussion but I came across that writeup along the way and thought cross posting here would be useful!

@bossybilbo That’s a really nice article and great write up on exactly how that speaker behaves in it’s original form.

This is the kind of perspective I think worth having before trying a complete 1:1 capacitor replacement. Don’t overhaul a crossover design you may not want to keep.

Which then brings me to a philosophical issue. Clearly, the new crossover fixes what many of us would see as deficiencies in the original design, but then I immediately have to ask, if you go through the exercise, are you going to be left with a B&W at all? I mean, if you bought the speaker because you wanted the B&W sound, and a speaker that performed like the reviews glorified, is this in the end the speaker you want? Or should you just sell the speakers and get yourself an excellent speaker kit and cabinets which performs as well as B&W you are going to overhaul?

BTW, there are definitely times when a new crossover fixes important impedance problems such as with several Infinity, some Focal and maybe in the future a Kef. In those cases the original frequency response stays about the same but the impedance is no longer as challenging. Worth doing, without hesitation.

I found this post and this 802D2 upgrade journey while asking myself the same question as the OP. The final replacement design is not documented in the writeup. However, they provide diagrams of the OEM crossovers and preform analysis of per-driver characteristics.

@allenf1963 , I think that part of the tubed pre in front of SS amp appeal might be related to heat and maintenance. Meaning that an amp that utilizes output tubes can run pretty hot and also requires occasional bias checks & adjustments and also that the output tubes are probably the tubes that are going to require the most frequent replacement, whereas the smaller tubes most often used in the pre will usually last a lot longer. A lot longer. Thus, a "hypbrid" set up of a tubed pre in front of a SS amp gives one a bit of the vacuum tube flavor without as much maintenance. Also, some might argue (and I might be one who would now also make this argument) that the preamp might have more of an effect on the sonic presentation than the amp.

About 30 years ago, I actually started out the opposite--a ss HT preamp in front of a tube amp. I didn’t think that my system really started to sing & sound delicious until a few years later when I upgraded to a tube preamp (a second hand Cary SLP-90) in front of my tube amp..

As far as other preamps (besides ARC) to consider, most everyone may tell you that whatever they are running with is the way to go. A few years ago I upgraded to a 6SN7 based Cary SLP-05 and it did impart sonic characteristics (more air and imaging resulting in a larger & more defined soundstage) that I truly enjoy, but it may not be everyone’s cup of tea.

Test 

This site needs more threads like this.  No BS, just straight up (good) audio advice .

Here's to Erik.

 I have a pair of 30 year old Klipsch Forte speakers.  I put all new caps in the crossovers and it woke them up.  Nothing fancy just new manufacture name brand caps.  So I think there is benefit in replacing caps that old but to the OP I don't think your speakers are old enough to warrant replacing the caps.   

Yes, thanks @erik_squires and all for all the purely informative feedback. Despite the inevitable few who sour the tone, I’ve always found Audiogon to be a place to exchange information and experiences. While I have great relationships with sales staff at my local dealers, I find I rarely get good good info from them. And sometimes their advice is downright terrible! I always find that once I sense there is a consensus on these boards, it’s usually worth paying attention. I never would have thought to audition the Diablo 300 amp, if not for these boards, and I absolutely love my amp!  I try to do my best to share my experiences as well.

Speaker capacitors are non-polarized, and using a polarized cap in a crossover is a Very Bad Thing. The best speaker caps are Metallized Polypropylene (MPP) because of their lower losses and self-healing capabilities. All Polypropylene (APP) caps have longer life but higher losses and are typically found in power supply use. Non-polarized Electrolytic capacitors are less expensive, but dry out and drift off value with age. Those are found in less expensive speakers. Newer NPE designs have improved a lot over what you'd find in a 40 year-old Advent. Back in the day, upgrading the high pass or piggybacking the low-pass caps in Advents was a common tweak with noticeable refinements in the midrange and high-end. 

Here are a couple of novice tips from another novice.

Capacitors have a direction, in/out. They have a label on them to tell you what end. goes where. If you install them in the wrong direction they may blow up. I had a friend had one go off in his face. That’s when he quit electronics.

Do not use flux!!!!  

Buy a quality iron that gets hot enough. It needs to be hot so that it will melt the solder on the board without getting the capacitor and surrounding components overheated.
I highly recommend that you go on eBay and buy a $15 amplifier/speaker kit for practice soldering.  Learn how to sweat a capacitor out of the board after you’ve installed it on your practice kit. (You Tube) You will need that skill to remove a cap from the crossover board without destroying adjacent components. Not as easy as it sounds. 
 

Bent

 

+1 @erik_squires great summation on preserving high quality speakers!

@allenf1963 In my mind the vintage AR and modern AR are very different sounding beasts, so be careful to ask which models people are recommending. I find the old AR + B&W to be a terrible but common combination resulting in a sound too lean and lacking meaningful punch. Modern AR sounds almost too neutral.

For vintage tubes you owe it to yourself to listen to Conrad Johnson.  Juicy, great imaging, maybe far too sweet for some.

I must say on these speakers if your want to change the Caps, it is your money and sounds like a guess. I would only say whatever grade of caps used, get the EXACT same grade, as like in Mundorfs', Not all are the same. I just replaced the Caps in my surround speakers from Solen to Mundorf, but I went for a lesser grade without looking at the reviews. Big mistake, I wish I had kept the Solen Caps. Just because you chose a brand name like Mundorf, that does not mean it is the best choice for that speaker and the engineers at B & W surely studied the qualities of the caps they chose when they designed their speakers. THat is not saying that you might prefer a different sound out of your speaks.

if you're going to upgrade to new internal wiring use OCC single crystal wire it has been proven for over 50 years now to be the best wire for audio far superior to anything ofc.

@erik_squires and ​​​​@mofojo,

Thanks for the input.  I acquired a beautiful pair of Klipsch Forte II with Crites Crossover upgrades a couple of years ago, and I'm trying to find a Vintage Preamp / Amp setup to hit the sweet spot.  I want a Tube Preamp (I've heard nothing but praise regarding Audio Research Company Tube Preamps, just trying to find the right one at a good price).  This will be a turntable only system for a 3rd listening room I'm putting together -- so I'm trying to be budget friendly on the Preamp and Amp. 

Any other Tube Preamps I should look at other than ARC, and any suggestions on an Amp to pair with it?  One route I have in my pocket already -- I bought two of the Nelson Pass Amp Camp kits a couple of years ago that are just waiting on me to build them.  I had thought about running them as Monoblocks with the Preamp.  Again, any thoughts?

Thanks, as always.

I’ve changed crossover components, so you’ll not get any disagreement from me.

If you are looking for an even better improvement, grounding the housing, and the front and rear plates is something I thoroughly recommend. Once the plates are grounded there is no contamination. It’s not until you experience the difference, that you appreciate the implications.

Of course tube preamp and ss amp is a popular combination. Get a good portion of that tube goodness distortion whatever and still have slammin bass. 
 

Also I agree don’t mess with the crossovers in the BWs unless you don’t like the sound and want to change somehow. The chances of improving it to your likeness is a pure crapshoot. 

Or too much heat in the room.

Hey @allenf1963 - I'm not sure if this is now standard, but the best example of this tube/solid state marriage is with very hard to drive speakers.  Electrostatics for instance are a classic reason for doing this.  A lot of tube amps will wilt in the high frequency range.  Some of my favorite combinations with Martin Logan speakers was with Conrad Johnson pre's and a solid state amp.  Of course, there are exceptions! So this is not an iron clad rule.

For some it's that tube/tube is too much flavor.  Too much euphonics together, so using tube/ss is like half way between. 

Yes for sure a great speaker to upgrade , great drivers and cabinet.

Xovers a bit bright I helped rebuild a few years back, even when they went with upper mundorf capacitors they are a bit brigh5 by nature.

and cheap resistors , path audio resistors highly recommended, 

the new Mundorf ultra a npbit more detailed but neutral capacitors  depending on your budget.

Hello NYEV!  I have never failed to get a serious improvement by replacing crossover capacitors. I have tried many serious brands. I like the Mundorf KRP series. They sound better than Solens, Auricaps, and several others. Replace any electrolytics with "real" capacitors also. You can get a huge variety of parts from Parts Connexion in Canada (no sales tax). They are quick shippers. I get all my "fancy" parts from them. Be sure to use rosin core solder. Happy listening.

Erik,

Fantastic job taking the time and patience to explain your answers to Nyev's original and follow-up questions, and doing so without an INKLING of bravado, elitism, or any air of superiority.  Sadly, this consideration of using basic skills of humanity is a lost art on Social Media -- especially this site at times.  Thanks for the audio lesson.

Now my turn.  Maybe it is just the ads, audio sites, or Audiophile setups that I tend to notice, but why do the majority of gear setups utilizing separates tend to have a Tube Preamp paired with Solid State Amps?  To me, it seems that if you are wanting the "Tube Sound and Experience", you would utilize tubes both in your Preamp and your Amp (along with your Phono Preamp).  What am I missing or not understanding?  If you can make it as easy to understand as your response to Nyev, I should be golden!

Thanks.  Allen

Good job Eric. 😁

FYI,

The white caps are Mundorf MKP.  Their low end film caps.  Quite smooth and dark, most likely in the woofer low pass.  The others are some version of Mundorf Supreme.

B&W as well as Magico are among their big OEM customers. Some of the B&W bookshelf speaker lines were different ONLY by the cap quality.

I personally find Magico and their new new supreme line, the Supreme Evo, to sound splashy, with too much fake color and air.  You can find prices at Madisound or Parts Connexion. 

Personally I'm a bigger fan of Clarity and Jupiter for any top builds I consider.

@erik_squires , thanks for confirming!  Interesting stuff for sure.

I just looked. They are all film caps. They will outlive you and me.

Leave them alone. You'll only degrade the value of your speakers.  Get a kit from Madisound and roll it to learn about caps and sound quality.

@erik_squires , thanks for the explanation.  The 802 D2's have two crossover boards - one for LF and one for HF/MF.  The HF/MF board has 3 caps, and the LF board has 2 caps.  All caps are VERY large.  Can't read the values for all caps, but I can see that some are 4.7uF and others are 100uF.

Here are links:

HF/MF Crossover

LF Crossover

Assuming the 100uF capacitors used by B&W are the electrolytic ones as you mentioned, is the advice to replace them with the exact same capacitors, or just caps with the equivalent values - after > 25 years?  

Thanks

So, the idea that caps wear out is about the electrolytics. They are wet and tend to dry out over time. Old caps, made in the 80’s and 90’s or before we know would leak/dry out in about 20 years. Newer electrolytics are actually more reliable than that.

In high end speakers these caps are rare but when used are usually for the high values (50 uF or more) and low frequencies because they are cheaper and much much smaller. Find your largest 3 caps and you’ll probably find your electrolytics.

Specifically, these will probably be bi-polar electrolytics, as those again are improved from before. Power supplies use polar electrolytics, which have terminals labelled.

@erik_squires lol, thanks and okay, sounds like it was a bad idea!  You mentioned I might need to check the electrolytic capacitors in several years.  Which caps are these, and how do I distinguish them from the film caps?  How do I check them?  

Hey Nyev,

No. Don’t do that. Change your speakers.

B&W 802s use mid-high end Mundorf film caps in most places. They are a distinct part of the B&W’s character. Also, those film caps will last hundreds of years. It’s the electrolytic caps that may go out after 25.

If you want to experiment with capacitor rolling pleeeease don’t use new-ish, high end B&W’s to start with!! 🤣 Get a kit speaker and play with it. You’ll have a lot more fun, do a lot less damage and learn a great deal more.

There are times when I strongly recommend people change their crossovers. Some of the Infinity speakers had notoriously bad impedance curves which new crossovers fix.  Focal uses Solen/Axon and even a modest replacement to Mundorf MKPs is a huge improvement.

In several years you might have to check the electrolytic caps in your speakers.  Until then I'd leave them alone.