XO capacitors, do they matter?

Marbles · « **on:** 3 Apr 2005, 03:22 pm »

I'm having a set of speakers built, and the builder doesn't really beleive that XO caps make that much of a difference.

My questions are, in your opinion, do different caps sound different?

What in your opinion are the best sounding XO caps.

Speaker design is a 3-way 10" woofer. 5 inch mid, ribbon tweet.

Thanks

JoshK · « **Reply #1 on:** 3 Apr 2005, 03:42 pm »

Is it Dennis Murphy?

JoshK · « **Reply #2 on:** 3 Apr 2005, 03:53 pm »

The reason I ask is because DM has a lot of experience building speakers, and there is nothing quite like experience. I think that it comes down to personal opinion a bit. Another very respected speaker designer in the DIY arena is Jon Marsh who frequents htguide.com and he is a believer in using high quality caps in key locations only and not throughout the xo.

I myself haven't done any experimenting, but I don't really take manufacturers word on the matter as gospel because they have an agenda when it comes to premium xo. They add another $60-200 in premium parts and the end result goes up $2000+. Doesn't exactly equate with me. I'd rather swap out parts inside the XO myself, or bypass the tweet cap with a premium cap. That is another option, bypassing a standard cap in the tweeter location with a nice one.

As far as which caps are best, I think this is going to come down to taste. Some like AudioCap Thetas, some like Sonicap Platinums, some like VenHaus' premium caps, TRTs, etc, etc.

zybar · « **Reply #3 on:** 3 Apr 2005, 04:13 pm »

Quote from: Marbles

I'm having a set of speakers built, and the builder doesn't really beleive that XO caps make that much of a difference.

My questions are, in your opinion, do different caps sound different?

What in your opinion are the best sounding XO caps.

Speaker design is a 3-way 10" woofer. 5 inch mid, ribbon tweet.

Thanks

Hmmm....wonder what that speaker might be?

I had the same discussion and he wasn't too sure about the cap changes either. I am probably going to try the VH Audio caps.

I am going to have the crossover put in an external enclosure so that things can be easily modified and/or bypassed alltogether.

George

Marbles · « **Reply #4 on:** 3 Apr 2005, 04:23 pm »

In all honesty, it was a passing comment that the maker mentioned, and I just wanted to get opinions before I went back to him.

He is more than willing to make any changes I have requested.

I got the opinion that he really doesn't think speaker cables make much of a difference, but he is willing to work with Robert Schult to have Ridgestreet Audio internal cabling, and to use Cardas Patented binding posts.

I was thinking that as long as I'm looking at every little thing, I might as well look at the XO caps at the same time.

He DID mention the option of external XO boxes, but internal looks much neater.

Occam · « **Reply #5 on:** 3 Apr 2005, 04:32 pm »

No expert opinoin by a suggestion - Have your crossovers housed in boxes external to the speakers. Wooden cigar boxes are nice for that task. Then, if you decide you wants to play slap and tickle with your crossover (or go line level crossovers and multimaping) its made quite a bit easier.

You might also consider compromising your old school speaker builder and involving him in the selection of caps, i.e. send him a couple pair of Vishay MKP1837.01uf (Mouser <$2ea) and suggest he try them for bypassing series caps and ask his opinion.....

Marbles · « **Reply #6 on:** 3 Apr 2005, 04:39 pm »

Quote from: Occam

No expert opinoin by a suggestion - Have your crossovers housed in boxes external to the speakers. Wooden cigar boxes are nice for that task. Then, if you decide you wants to play slap and tickle with your crossover (or go line level crossovers and multimaping) its made quite a bit easier.

You might also consider compromising your old school speaker builder and involving him in the selection of caps, i.e. send him a couple pair of Vishay MKP1837.01uf (Mouser <$2ea) and suggest he try them for bypassing series caps and ask his opinion.....

Love the slap and tickle line

Great suggestion on the "involving him in the selection of caps"

Thanks..

Really once the XO is set, I doubt I do any experimenting. The speaker will have two sets of binding posts so I can easily bi-amp, but not tri-amp.

The passive XO is supposed to be VERY good in stock form and the only playing I plan to do will be with room correction software, and not with speaker correction...

Occam · « **Reply #7 on:** 3 Apr 2005, 05:28 pm »

Marbles - I realize that you might not be that interested, but for the less sanguine out there -

A great low cost source for great sounding caps are industrial motor run caps. I've been mucking about with a rather generic Amtrad 15uf motor run polypopelene in oil, $4, (in a different application) was bowled over. While an external crossover box might be intrusive, your options for crossover implementation, as they could well change with evolving technolgy/fashion, is not nearly as constrained.

One man's take on crossover caps (including oils) -
http://home.zonnet.nl/geenius/Cap.html

PSP · « **Reply #8 on:** 3 Apr 2005, 08:44 pm »

I just put Sonicaps into my GR-Research Paradox 3s and it was a huge improvement. I'd listened to the stock P3 (with Blackhole 5, no other mods) for almost two years. I was able to buy the Sonicap upgrade from someone whose P3s had been damaged by UPS in shipment, but I didn't put the caps in for many months (too many other audio projects). In the meantime, I'd read a several exhaustive threads on the Madisound forum in which cap swaps at two large DIY meets were apparently inaudible to most folks attending. Many people concluded that they would be using cheaper caps in future XO designs.

So, it was after reading/studying this thread that I went ahead and put the Sonicaps into my P3s in place of the stock Axons... truly, I expected nothing. I was just being thorough, completing a job I'd long intended to do. What I got, to my great surprise, was a very significant improvement in instrumental timbres, loss of just a little edgeiness with an increase in resolution and inner detail. I was (and am) honestly thrilled with the result.

Some of the folks at the DIY meets (who couldn't pick capacitor swaps) are among the most respected people doing DIY speakers these days. I beleive and respect what they reported. They were very careful with methodology... but two months ago in my listening room I heard a big improvement that I really didn't expect to hear. Don't ask me why, and don't ask me to go back to the old caps either!

Peter

EProvenzano · « **Reply #9 on:** 3 Apr 2005, 09:14 pm »

Here's a nice solution I've seen in the past....
Have your designer mount the XO on to a removable access panel on the back of your speakers. You get the clean look you want and can still access the XO with ease.

Good luck!

Ribbon tweet, 5" mid, and 10" woof hey? hmmm....sounds interesting

brj · « **Reply #10 on:** 4 Apr 2005, 08:51 am »

Not that it matters to the original question, but isn't the mid for the speaker in question just over 7 inches? (i.e. Seas W18EX is 18 cm.)

I have to admit that I'm curious about people's cap suggestions as well, although I don't specifically know what brand/type of "high quality crossover components" are standard in the speaker. (The quote is from the website.)

The concept of externally housed passive crossovers appeals to me, as it simplifies later experimention with active crossovers/bi or tri amping/speaker correction/room correction. Housing the passive crossovers in an easily accessible compartment in the speaker itself would be even better aesthetically, provided that it is just as easily bypassed at a later date.

StevenACNJ · « **Reply #11 on:** 4 Apr 2005, 10:42 am »

I have rebuilt several pairs of factory speaker crossovers. Mostly replacing Solen & Bennic caps.

I use all Sonicap's with a Sonicap teflon to bypass the tweeter cap. I have also used Mundorf Silver & Oil Supreme as tweeter bypass caps.

Here is a link for cap test results, it has been posted previously, but it is interesting reading.

Good luck with your new speakers

http://home.zonnet.nl/geenius/Cap.html

skrivis · « **Reply #12 on:** 4 Apr 2005, 01:36 pm »

Quote from: Marbles

I'm having a set of speakers built, and the builder doesn't really beleive that XO caps make that much of a difference.

My questions are, in your opinion, do different caps sound different?

What in your opinion are the best sounding XO caps.

Speaker design is a 3-way 10" woofer. 5 inch mid, ribbon tweet.

Thanks

I don't agree that caps have a "sound" unless they're simply the wrong cap for the circuit and throw things off so that the circuit no longer works properly.

One problem with a lot of the "magic" caps is that they're huge. That adds inductance, and can also make them more prone to being microphonic.

For x-overs, it depends upon the value needed. Polyester film caps do quite well in x-overs. I suppose you could try bypassing electrolytics with film caps for larger values, but it hasn't been proven to me that this will make a huge difference.

Wire is wire. Any beneficial effects of using "magic" wire is going to be so many orders of magnitude below the very real problems with most speakers that it's meaningless.

For instance, many speakers use steep slopes for x-overs or the enclosure itself. Not a good thing... It's likely that this will completely bury any improvements you might try to make "after the fact" by trying to patch it up with wonder caps and vampire wire, or space shuttle coatings...

markC · « **Reply #13 on:** 4 Apr 2005, 09:27 pm »

I swapped out the stock caps in my soliloquy's for sonicaps. Great improvement in clarity and presentation. In fact the new cap mod brought out the short commings of the top end of my ss amp-I sold it and replaced it with hybrid.

jackman · « **Reply #14 on:** 5 Apr 2005, 12:01 am »

I have been holding off on answering this question becaues I'm not sure. It depends on what you have in your speakers. I like the Sonicaps that were in my Ellis and liked the Audiocap PPMF's that were also in the previous version of the Ellis. I've tried some really slick Audiocap Theta caps on some speakers I have (tweeters) and really like the sound but I don't know if I would pay the $42 per cap (10uf). I believe you reach a dimishing return after the Sonicaps in a speaker.

Dave Ellis has always been a proponent of better caps in the CDP. Maybe the high $$$ caps have a better impact in your CDP versus the speakers. Plus, the values are lower and more economical.

Occam · « **Reply #15 on:** 5 Apr 2005, 03:28 am »

Quote from: skrivis

...One problem with a lot of the "magic" caps is that they're huge. That adds inductance, and can also make them more prone to being microphonic. ...

How would the inductance of these large magic caps be a problem when used in a x-over? Over what frequency range would this added inductance be problematic? How much inductance are you talking about? Could you work out an actual example with ballpark numbers?

Thats quite interesting that these large caps are more microphonic. I'm quite familiar with microphony with many ceramic caps, but this is a new one, and I'd like to learn more. Could you provide a reference, a URL?

TIA,
Occam

skrivis · « **Reply #16 on:** 5 Apr 2005, 04:15 pm »

Quote from: Occam

How would the inductance of these large magic caps be a problem when used in a x-over? Over what frequency range would this added inductance be problematic? How much inductance are you talking about? Could you work out an actual example with ballpark numbers?

Thats quite interesting that these large caps are more microphonic. I'm quite familiar with microphony with many ceramic caps, but this is a new one, and I'd like to learn more. Could you provide a reference, a URL?

TIA,
Occam

That's what I get for posting before I've had my coffee.

ESL is probably not a factor in crossover networks like it is in active circuits. Microphonic caps aren't likely to cause problems in crossovers either.

I once calculated the resonance frequency of a large Wonder cap to be 25 KHz, but I imagine most caps will have more sane values for this. (>250 KHz I imagine.)

I checked figures for some film caps on the net, and it looks like 15-50 nF is common for ESL. That isn't going to have an appreciable effect on the crossover network. However, it is an unintended consequence of swapping caps, and you might just replace caps with low ESL with others that have high ESL if you're not careful. I suppose the slight effect could account for some of the differences people hear when swapping caps.

I think a good general statement would be that ESL should be as low as possible, but other factors may be more important in a crossover.

As for microphonics, I first noticed this in a guitar amplifier. A friend had an amp with some problems and it was mainly a preamp tube that was microphonic. (It can sound like reverb, can cause squealing, and can even sound like a voice coil has become detached on a speaker.) After replacing the tube, I rapped the chassis to see if there were still problems.
What I found was milder than a bad tube, but still audible. I traced it to some large film coupling caps. I replaced them with, I think, Sprague Orange Drops of the same value and the problem went away.

Guitar amps often have the speaker in the same cabinet as the amp, and the preamp can use insane amounts of gain, so it's probably more noticeable with them, but I wouldn't be surprised to find that it can have an effect with stereo equipment too.

SteveC · « **Reply #17 on:** 22 Apr 2005, 05:00 pm »

The angry mob, with limited (albeit very technical) experience, has not convinced me that XO caps don't matter. Setting aside knee-jerk opposition, subjective hysteria and other insidiously self-serving rationalizations; I bet they do. It's OK to use better-quality caps, and tighter tolerance is also desirable. I like Mundorfs.

_scotty_ · « **Reply #18 on:** 22 Apr 2005, 09:24 pm »

SteveC,which Mundorfs did you use. I have been considering substituting
them in place of Hovlands.
Scotty

SteveC · « **Reply #19 on:** 22 Apr 2005, 10:33 pm »

Scott;

I'm using some silver/oils for smaller values and mids' highpass, but mostly the regular Supremes.