Best Electrolytic Caps for Non-Polarized (nonpolar/bi-polar/bipolar) Applications

[FritzS]

But You could made this and bypass with a very good foil condenser. But don't use diodes.
Both electrolytic capacitors are identical, the total capacity is half of the individual capacity. This circuit is often used in the audio sector.
Marantz in the CD/SACD players in the output.
Marantz uses Elna Silmic for this.

 

[FritzS]

Look at here
Michael Percy Audio
https://www.percyaudio.com/

Parts ConneXion
https://www.partsconnexion.com/capacitors-ele.html

 

[richloh]

Due to space constraint but at least having isolated and rare reference of Nichicon EP bipolar 47uf 25v in other threads here and other forum, looks like I have to and will proceed with it at the below mounted power section with little airflow while keeping the Nichicon ES bipolar 47uf 25v in the preamp section mounted on top of the power section and directly below under the ventilated cover.

Yes, it is a 15 yrs old Kav-400xi and glad to find 125c gyc smd capacitor also ordered while non available for 47uf 6.3v ones in required 4mm diameter which I ordered Panasonic FP 105c at half impedence compared to others.

Other e caps will also give the usual audio grade nichicon @85c a miss and using Panasonic FC, FR or FM @ 105c while had ordered the 4x15000uf 63v mundorf power 125c per Canadian Marton Poulin's recap mod in view of again size constraint and only 85c options available from Nichicon, Wurth, Cornell etc. seen used to replace stock 8x 6800uf 63v Nichicon LS ones.

Cheers.

 

[richloh]

But You could made this and bypass with a very good foil condenser. But don't use diodes.
Both electrolytic capacitors are identical, the total capacity is half of the individual capacity. This circuit is often used in the audio sector.
Marantz in the CD/SACD players in the output.
Marantz uses Elna Silmic for this.

View attachment 1198203

Tks tks but 85@c and space constrain make this not preferred nor even doable even if soldered on solder side.

Will just use the UES for preamp and UEP for power pcbas respectively 🙏

 

[tiefbassuebertr]

Thank you for the internal images and your explanations in post #23 of Krell's KAV-400xi.
A lot of Krell devices manufactured after 2000 refurbishing I don't like because caps replace by better parts isn't possible due too small available space as you have already mentioned.
Another issue is the fact, that no logo is to find on SMD electrolytics - go to
https://www.diyaudio.com/community/...evices-for-surface-mounted-technology.161369/
That's an important reason why I always make sure when buying used amplifier equipment that it's an old device from 70th or 80th that doesn't have these problems.
An example is Audiolabor's ES200 power amplifier
https://old-fidelity-forum.de/archive/index.php/thread-23346.html
https://audiolabor.de/index.php/2015-08-05-14-38-29/es200
https://audiolabor.de/images/audiolabor/service/es200-service.pdf

 

[NormB]

I would just use Nichicon Muse UES series capacitors. They are without doubt the most inert sounding/behaving non-polar electrolytics available that I know of. Thats even comparing obsolete electrolytic capacitors ie. Rubycon Black Gate or Elna Cerafine.

I use them in all of my gear where a film/foil cap won't fit or would cost too much. Distortion measurements are close to a good MKP film cap for single digit voltage drop and in coupling applications between stages.

Well, since they're no longer mfd., the Nichicon Muse UES series ( specifically UES1H4R7MEM) does anyone have another recommendation for a NONpolar 4.7 uf/25-50V capacitor replacement?

BTW, I bought ten of these from a vendor in China (yeah, probably counterfeit), values range from 1 nF to 7.25 uF with five in the 5.1-5.2 uF range and comparing the outer film to Nichicon parts spec sheet it's a pretty good counterfeit, I think.

Thanks.

Norm

Photo from Technics ST-9038 audio output circuit. Have replaced IC with OPA2604 and am about to add decoupling caps to +/- rails, replace the 35 (?) year old coupling caps (the aforementioned BP Muse I've looked for) maybe roll in an OPA2134 IC for fun/clarity.

 

[richloh]

Plenty of legitimate Nichicon UES from reputed digikey, rs component, mouser, parts connexion etc.

Will not buy from China resellers to worry forever if genuine or not.

Cheers.

 

[richloh]

Another issue is the fact, that no logo is to find on SMD electrolytics - go to
https://www.diyaudio.com/community/...evices-for-surface-mounted-technology.161369/
That's an important reason why I always make sure when buying used amplifier equipment that it's an old device from 70th or 80th that doesn't have these problems.
An example is Audiolabor's ES200 power amplifier
https://old-fidelity-forum.de/archive/index.php/thread-23346.html
https://audiolabor.de/index.php/2015-08-05-14-38-29/es200
https://audiolabor.de/images/audiolabor/service/es200-service.pdf

Most welcomed and will update according as someone had finally and nicely shared schematics of kav-400xi (300il power is same).

These now available Nichicon gya and gyc at significantly higher 125 and 135c are newly introduced and should keep the hot krell happily running for a much longer time to avoid killing other electronics 🤞🤞🥳🥳

 

[NormB]

Had been advised by tech. elsewhere to up rating to 50v.

Figured hey, original spec cap at 25v worked/works, so found 4.7uF/25V BP Muse and ordered some.

I'm sure it'll be fine.

Tried deleting post - too late.

And @richloh - I had a moment's weakness. Will NOT happen again.

Thanks for all the fish!

NB

 

[richloh]

Hi Norm,

Some 50v are way too big ... UES are already oversized at same 25v in the kav-400xi as shown below and in not preferred longer leads wrt induction and other nasties .. for your consideration only.

Weak moments .. me always ... but spent enuff 35 years among china factories and recent decade with most but certainly not all chinese resellers to be aware to avoid if at all possible.

If needed, revert to ChiFi sellers that are quite a few and not 90% of resellers with just a web shops without knowledge of what they are selling ... manned probably by some ladies that part time as waitress or receptionist or students 😰

Cheers.

 

[dotneck335]

NOT the MUSE ES series, but.....
UDB1H4R7MPM1TD 4.7uF 50v 5x20mm ≥3000 available @ Mouser @≤$0.85 each

 

[NormB]

Thanks, @dotneck335 - Mouser had these in stock: https://www.mouser.com/ProductDetai...JUsDEtgP3lQ==&countryCode=US&currencyCode=USD

Plus they’ll most likely fit in the available space.

I’ve used MUSE before in other applications and liked what they did/didn’t do.

 

[NormB]

Hi Norm,

Some 50v are way too big ... UES are already oversized at same 25v in the kav-400xi as shown below and in not preferred longer leads wrt induction and other nasties .. for your consideration only.

Weak moments .. me always ... but spent enuff 35 years among china factories and recent decade with most but certainly not all chinese resellers to be aware to avoid if at all possible.

If needed, revert to ChiFi sellers that are quite a few and not 90% of resellers with just a web shops without knowledge of what they are selling ... manned probably by some ladies that part time as waitress or receptionist or students 😰

Cheers.

View attachment 1203029

I took pictures - I can’t find at the moment - of a REVOX PR99 output board I’d recapped where I didn’t like the close fit of the capacitors with a metal shield, so I put the caps on the bottom of the board, legs bent at 90 degrees a little like your UKA (blue) caps. Worked fine, no risk of ground loops.

BTW: I got a 100% refund from the Chicom vendor on ePay. Caps went right into recycling bin.

 

[richloh]

Hi, Anyone can share your knowledge on what brand/mfgr these non-polar capacitors used in input coupling of KAV-400xi ? Googled and searched even by image but failed to find any info. Thanks !

 

[NormB]

https://www.niccomp.com/

 

[richloh]

Hi NormB, Many thanks !!! Would not have been able to figure this one out and it seems not common in this part of Asia. With appreciation and cheers !

 

[NormB]

I had a similar issue with a trim pot earlier this year, STILL haven’t figured it out.

In your case, I did a search on Duckduckgo for capacitor manufacturers and capacitor manufacturer logos - I couldn’t tell if that was an “N” an “M” or a stylized Russian “L” except the rest of the cap was in English. Took about two minutes.

I did manage to find workable substitutes, but wanted to find SPECS on the part (wirewound, carbon, cermet element?), wattage, etc.

It’s from a Chicom Willsenton R8 amp biasing board.

Oh, and you’re welcome.

 

[NormB]

ANOTHER, more general question for the knowledgeable here:

TECH-cap is a somewhat defunct American capacitor manufacturer.

I have a TEKTRON 300b SET amplifier populated with their capacitors.

How do I find the SPECS/data on their caps? ESR, Ripple, Q, etc. I’ve exhausted the usual sources, Elcodis among others.

Thanks.

 

[richloh]

Hi NormB, Sorry to hear and wish I could reciprocate yr help but google lens search yield no success ... really hope some members can help advise like you did for my case. Good luck 🙏

 

[rayma]

I have a TEKTRON 300b SET amplifier populated with their capacitors.
How do I find the SPECS/data on their caps? ESR, Ripple, Q, etc.

Just post the schematic and you'll get suggestions for replacements.