Best Capacitors for Crossovers

I am now in the tweaking stage of trying different caps in my crossovers for my DIY homemade 2 way. I presently have and will soon try a 5.6uf 800 vdc +/- 2% Jantzen Audio Silver Z-cap.

I see that Mundorf, V Cap get a lot of accolades, and the Dueland are quite pricey.

Does anyone have a favorite?

I am trying to cross over at about 4500HZ at 6db.


This is the Tweeter I’m using.

Aurum Cantus G2Si Ribbon Tweeter


  • High 96 dB sensitivity is great for efficient designs
  • Excellent high-frequency extension, can be used as a supertweeter
  • Extremely fast transient response allows reproduction of the finest details
  • Smooth and effecient frequency response from 1,700 to over 20,000 Hz

I highly recommended Jupiter copper foil caps. I prefer them to Duelund and have tried both. Far superior to Mundorf in every way, but most especially in the mids and micro details. The Jupiter cap is very linear with no part of the sound spectrum highlighted.  I find the top of the line Mundorfs a tad boosted in the highs. The Duelunds a tad bumped in the upper mids. The Jupiers are so smooooth! 
You might want to try DIYAudio, but in the "affordable" boutique crossovers my favorites so far:

Clarity MR (now CMR)
Clarity ESA
Mundorf MKP
Mundorf Supremes

Yeah, I list the Supreme’s lowest due to an artificial Disney-like sheen or scintilation. It is NOT natural, you don’t hear it when listening to live music, but if you like it, do it! :) Magico is enamored of the entire Supreme line and why I’m not enamored of Magico. :) Clearly I’m in the minority.

Solen’s have been such a mixed bag now I refuse to even look at them. I hear good things from the top line models, but meh, not about to try them.

I also like Audyn Truecopper (Bypass values only)

The Mundorf MKP is a great upgrade for many, and the prices are hard to beat.
@grannyring Thanks for that. I've been seriously considering the Jupiter line, especially since Soniccraft has them on sale often.

I have a pair that sounds very nice, but I am thinking about completely re-doing the crossover design, and Jupiter caps in the tweet would be just the thing. :)


Post removed 
Technology before brand.

There are two main types of quality caps: metallized, and film-and-foil. The former are cheaper, the latter better: by better, I mean smoother, more refined, more detailed.

Dielectric thickness doesn't matter very much, but metal thickness does. Just about anything thick enough to be wound up on a spool is thick enough for sonics, but a deposited conductor is a different matter.

Construction is also important. The larger the capacitance, the more the cap can suffer from inductance. MIT Multicap have a connection scheme that minimizes this. Duelund has a flat pack topology which is just about optimal.

Polypropylene tends to sound pretty good, but compared to styrene, is dull. PTFE (teflon) sounds a little bright compared to styrene. Styrene is, to my mind, the most neutral of the conventional dielectrics. These are the films.

For metal, the best is one which connects easily (usually solders easily). Those are silver, copper, and tin. These are the foils.

Now to the brands. I have used many, and MIT are my favourites. Solen f&f are less expensive but less good in my opinion, except for their PTFE f&f, which are as good as anyone's. Relcap makes a good capacitor. For the very best sound, I use MIT RTX series, which is a styrene / tin capacitor.

YMMD. Hope that helps.

Munforf supreme is a good standard ,med vost nice imdging warm natural presentation for a xover for Tweeter 
Without question I have used many times the Munforf Silver oil.slightly warm and natural.Very good image depth and air . Best value hands down rated very high 
Is the Audyn True Copper caps.  Very large using a lot of Copper foil 
Big and bold nice and rich, open and excellent image depth 
Go to Humble homemade hifi capacitor tests .very accurate Tony has helped me several times while living in Europe.  How much room also is important. 
Inductors always loved the Jantzen  inductors from Denmark.
With resistors Mills are warmer, but for resolution the ohmite gold are very good 
As are thd Munforf white reference . The best and warm may be the Path audio 
Made in Poland .the same company that make the Khozmo volume attenuator. 
Solder very important . WBT,CARDAS,, Mundorf, Johnsons 4% silver very good 
And a best buy. Wire I use Neotech 0- Crystal Copper Teflon wire .

Concerning the new ClarityCap CMR and CSA ranges, it would be a conflict of interest to comment on their performance relative to other brands. However, it seems fair to mention that these models are qualitatively different from other metalized film capacitors with respect to their copper litz end caps. This contrasts with other metalized film caps(e.g. Mundorf, Solen) that use traditional tin-zinc end spray to bridge the metal film layers at the capacitor ends. End sprays atomize and oxidize upon deposition, forming grain boundaries of variable impedance and phase anomalies that worsen with diameter. The performance advantage of a copper end relative to tin-zinc increases with diameter. This particularly favors use in applications involving higher capacitance and larger dimensions as found in crossovers.

I just finished replacing 6uf and 17uf MR with CMR in my much-modified Merlin VSMs. This was a big step up.

ClarityCap OEM Sales

Thank you all for your opinions and suggestions for web site reviews. They have been very helpful. I will try to obtain some of the caps suggested for comparison.


For a tighter connection, I soldered with silver solder silver spades to the cap leads. After everything is connected, one of the caps does not work!

Now, I don’t know if the cap was dead from the get-go.

But, can the heat from the use of the soldering iron ruin the cap?

While I admire technology, I believe in results. I can take pretty much any DAC chip, put it on a circuit board and make it sound like garbage. Same for most technology. Beryllium tweeters, AMT, etc. can be implemented well and poorly.

I think knowing about the capacitor tech is good, but results are results.

And as always, let your own ears be the judge, not me nor a website.



Hey @dgarretson

When will CSA range become available in the US?

I'm happy to note the CMR is already orderable from Parts Connexion.



Possible but unlikely.  Avoid shortening the leads, and make sure your iron is hot enough, and the tip wide enough.

Melting solder should take like 5 seconds or less! If you are sitting there for half a minute waiting for solder to melt, then yes, you could definitely have injured the cap.
If you are going to compare caps, I would use screw in terminals or even speaker binding posts. You'll definitely hear relative differences that way.
@dgarretson Technically, it is only a conflict of interest when you serve two masters. Promoting your own wares over another may be biased, but not a conflict of interest. :)

For instance, if you were being paid by a rag/mag to do "unbiased" research on capacitors, but were also being paid by Clarity, that’s a clear conflict of interest, especially if undisclosed.


I have a 3rd order filter for some of the most revealing tweeters in the world on the way, the Mundorf AMTs. I’ll post when I have them in circuit.

They behave practically as if they are massless and are easy to integrate with drivers thanks to a very smooth frequency response and flat impedance above resonance.




I think I did have to hold the soldering iron for quite a while to get the solder to flow into the spade hole. The spade hole was impossible to crimp down. Later I learned that with a hammer I could bend the spade hole small enough that only a little of solder was needed.

Yep. Sorry my friend. Temperature controlled soldering iron with a large tip FTW!! :)
I should have added, this is the soldering station I use, from Aoyude. Includes various sized tips, which have been a god-send. Cheaper kits don't usually include extra tips. Hakko is the usual standard for soldering stations, but I think Parts Connexion may a knock-off even cheaper. Just make sure you get a variety of tips.

But for your testing, I'd really encourage you to stay away from soldering. :) Screw down terminals will be fine.


Unlikely you ruined the cap by heat to be honest. It is possible, but my goodness you would have to turn it up to 800 degrees or more and hold it there for a long time. By long I mean over a minute or two. 

Also, the best sounding resistor I have used is made by Path Audio. I think Parts Connextion sells them. Very good indeed and a tad expensive to be sure.

These new CMR caps from Clarity look interesting. Love to know if they sound as musical and lovely as the Duelund and Jupiter copper foils caps? While the V-caps are rated very well I never liked their uber detail and relative thin sounding character. I hope the Clarity CMR cap is not from that sonic camp? 
Vaguely, caps are often not rated to withstand more than 200 degree environments, electrolytics and film. Of course there are exceptions, and higher temp caps. Also, this is usually rated lifetime. LIke, 10,000 hours at 105C or something. The cooler they stay, the more life. The hotter, the faster they can die. Using high temp caps also means longer lasting in the same circuit.

I think this is very much in the scale of temperature we are talking about. Even low temp solder can’t melt until it reaches 360 degrees or so. So yeah, holding a soldering iron to the leads for a while can really damage a cap. I usually have my iron around 620-650 depending on how much metal has to heat up, BUT....

The time of exposure matters a lot. A quick hot iron can expos parts to less total thermal energy than a slow one, and therefore the internals of the cap will heat up less.

Anyway, this is all theory. :) The fact that the cap that failed was in fact exposed as I was worried about kind of explains it in my mind. :)

The cap is dead anyway. Try again and make sure you can solder fast. Lesson learned.



Side question: what do you guys recommend for a tweeter protection cap in an active system? Protection for DC on amp turn on, or eventual active crossover malfunction.

A good rule of thumb in an active system is the protection should be set two octaves below the tweeter crossover point. For my case, xo is 2000Hz so I'm looking at 500Hz. The calculations show the ideal cap for my tweeter and for 500Hz would be 65uF, which is large and expensive. Several of the top lines mentioned here don't even have caps this large.

Since it was only for protection I initially thought a less expensive cap would do. But the whole signal goes through it. What do you recommend?


Well, I received a replacement cap this morning, and this time no solder. It works!

But, as usual the sound is kinda bright. But there are some very good quality's. It's been quite a while since I have had new woofers, tweeters, crossover, wire etc. Any idea how long it will take for my Frankenstein project to sound it's best before I move on to a different arrangement?

I also have seen some breakers designed to reset after an overload event. Are these worth installing before the cap or tweeter?

About 2-3 days of continuous play.

You may be better taking this thread over to DIYAudio where you can post images like schematics and measurements.


Please let me know the components you are using. What caps and resistors etc.  This will help me better tell you what to expect and break in based on my experience with these various parts and brands.


*The Tweeter that is used =

Aurum Cantus G2Si Ribbon Tweeter, 6 ohms.


  • High 96 dB sensitivity is great for efficient designs
  • Excellent high-frequency extension, can be used as a supertweeter
  • Extremely fast transient response allows reproduction of the finest details
  • Smooth and effecient frequency response from 1,700 to over 20,000 Hz

*Capacitor that is used=

5.6uf 800 vdc +/- 2% Jantzen Audio Silver Z-cap.

*The Inductor that is used =

Jantzen Cross Coil Copper foil .27mh, 99.99 pure copper windings, 14 gauge, 500 watt rms

*Woofer that is used =

6.5 inch mid bass/midrangeWoofer.

This speaker is rated at 150RMS. It produces solid mid-bass and midrange response.

This woofer has an impressive frequency range of 60hz-7000hz.).

  • 1’’ Kapton voice coil Stamped steel basket Strong black paper cone Cloth edge Suspension
  • Bumped & vented pole piece
  • 8 ohm impedance
  • 30 oz. magnet

Specifications: • Power handling: 150 watts RMS/400 watts max

• VCdia: 1" •

Impedance: 8 ohms

• Frequency response: 60-7,000 Hz

• Fs: 94.3 Hz

• SPL: 88.5 dB 1W/1m

• Vas: 0.15 cu. ft.

• Qms: 2.97

• Qes: 1.27

• Qts: 0.89

• Xmax: 6.5 mm

• Magnet weight: 30 oz.

*No resistors.

Nice! Well that tweeter matched with that particular cap will give a very detailed sound that will certainly start off hot sounding. The Jantzen silver cap is known to be very detailed and tipped up in the highs. Even after burn in that personality will prevail. 

I have had great luck matching ribbon tweeters with copper foil caps from the likes of Jupiter. I had that combo with Raal ribbon tweeters and it was wonderful. I think burn in will be closer to at least 100-150 hours to be honest. 


Thanks for the info. I also wired the cap with the tweeters using .9999 silver cable. I know that when I had the Von Schwekert’s speakers as new they sounded pretty tight for about a month. I even ran one out of phase and moved the speakers together face to face for several weeks.

I am not too concerned at this time though. I know wire takes at least 200 hours to flesh out and what I am using is all new wiring, caps and speakers.

With my Pass Labs amp, I don’t want to play it continuously so it may take a month to fully develop. So, at that time I may experiment further with other caps.

NIce. I like silver, and copper, but really not impressed by silver/copper for speakers.


"Lustformusic" gave you great information; and that design came courtesy of  GREG TIMBERS; a very senior speaker engineer/designer at JBL. A great guy responsible for some of JBL's greatest speakers. From personal experience I can say he is a exceptional gentleman who really cares about music reproduction and customer satisfaction.My hat remains off to Mr. Timbers.
For wire I highly recommend a brand new affordable wire made by Duelund that copies and betters the wonderful NOS Western Electric copper stranded wire. Parts Connextion sells it for $10 a meter and it is very special. I have wired my complete system with the Western Electric NOS wire popularized by Jeff Day. This wire has caused many of us to sell of thousands of dollars worth of Aphile cable for better sound with the WE16 NOS cable. Well, the NOS WE16 wire is now gone and sold up! But Duelund has made a match that according to Jeff Day that is even a tad bit better. 

Forget all all you may have heard about stranded or tinned wire and buy some. I had to empty my brain of past experiences and reading on tinned and stranded wire, but when I opened my mind and heard this stuff I was taken back. So open and musical. You have to hear yourself to know. Check it out.


Active crossover is an idea. I was thinking of eventually getting a DEQX unit.


I read the attachment lustformusic added. I'm not sure I totally understand the concept. I need to read it again.

I am getting very good soundstage wide separation along with a pretty deep presentation. The upper frequencies are definitely pronounced at this point however.


I may try some of that wire.

Hey Ozzy, what caps are you trying right now?

If you are going to try 1 brand at a time but can’t burn them in, it will take you a while to try 2-3 brands. :)

Totally worth it to find another amp around the house to use for burn-in.



*Capacitor that is used=

5.6uf 800 vdc +/- 2% Jantzen Audio Silver Z-ca

Cool, never tired them. Troels Gravesen loves them, but he's sponsored. :)



I am using an active xo, and while I hesitated for a long while because of the digital processing involved, which rang so much as heressy within my preconceived notions, I am not going back. I'm still learning and perfecting the implementation - still haven't time-aligned my 4-way - yet it still sounds so much better. And in my case the setup is cheaper than the 2-channel I was running before.

DEQX, from what I read, is an excellent unit. If your only source is digital, then there are cheaper options that are more involved but also more flexible.

Just a little more info. I put the speaker crossover's in wooden boxes and made them external to the speakers. Seems like all speakers should come this way. Especially for tweakers (Like me).

Also, has anyone tried the speaker breaker from Parts express to protect tweeters? Now, I wired the tweeters using ultra pure .9999 silver wire, so I am reluctant to add a breaker with its crappy wire to the connection.

Best Capacitors for Crossovers

I am now in the tweaking stage of trying different caps in my crossovers for my DIY homemade 2 way. I presently have and will soon try a 5.6uf 800 vdc +/- 2% Jantzen Audio Silver Z-cap.

I see that Mundorf, V Cap get a lot of accolades, and the Dueland are quite pricey.

Does anyone have a favorite?

I am trying to cross over at about 4500HZ at 6db.


Best bang for buck Ozzy is the Solens. I was told by someone in the know that a few of the "boutique" branded caps are just re-badged Solens.

Cheers George

Ozzy, it’s really rare an audiophile blows a tweeter, unless you use a very low order filter and it’s too low an F.  In additon to the filter, there's usually resistors padding them down, so you have to work kind of hard to blow them.  Leave extraneous things like that out unless you are making a party/pa speaker.




I have tried the Solens and they are ok but they seem to compress the dynamics. The caps I am using have silver leads and silver wiring


I do like to play the Pass Labs amp pretty loud sometimes. I'm crossing over the tweeters at 4500hz. There frequency rating is 1700-20000+hz, 6 ohm and have a 30 watts rms rating .I have not added any resistors. First off, I am not sure what they contribute. Can someone explain? Is it for equalizing the levels between the tweeter and woofer?

I have been using the Purist break in disc quite a bit and I do believe the brightness is toning down.

I have tried the Solens and they are ok but they seem to compress the dynamics.

Really? I found the opposite, with all of them, when used in my ESL xovers, and even in my Plasma tweeter xovers, especially I found the SILVER METALLIZED POLYPROPYLENE to be vey good, but everything has to be perfect to handle these babies, because they’re so fast and clean.

Which ones did you try?, as there are quite a few models (8 I believe) that can do the job inside a speaker xover.

Cheers George
I've used those in my crossover with great success on a similar tweeter.

Now I'm waiting on some to arrive for my power amp.

Good luck.