It had to happen eventually... capacitor upgrade question for the Mainline

[Paul Birkeland]

Thanks for the pointer to the "Mundorf Capacitor 15.0uF 250Vdc MCap® Classic (MKP)"
I gotta ask, though, if this cap is significantly better, why not include it in the base build? It's only $10.82/ea. I assume they would be a little cheap in bulk or wholesale.

While there may be bulk pricing, I bet if we ordered 50 of them it would take 6+ months for them to arrive.  The caps that we get come right from the manufacturer and are nearly always in stock.  They are also metalized polypropylene, just like the Mundorf caps. 

Is it "better" or just different than the included caps?

I have no idea, you'll have to smoke it and see.  These are the Mundorf caps that best fit the phyiscal space.

mcandmar mentioned on page one that a high quality mundorf cap ("supremes at a minimum") would be warranted.
The "Mundorf Capacitor 15.0uF 600Vdc MCap® Supreme" is 41mmW x 106mm L - would that fit?
The "Mundorf Capacitor 10.0uF 600Vdc MCap® Supreme" is 36mmW x 106mm L - better fit?
The 10uF are $57.40/ea at MadiSound. (+$6 to $9 shipping)
https://www.madisoundspeakerstore.com/supreme-caps/mundorf-10.0-mfd-supreme-caps/

With your Mailine assembled in front of you (you will hopefully build the amp with the stock parts first), you can cut out a piece of paper that's the footprint of the cap in question and make that judgement call for yourself. 

What's the  sonic difference between using the 10uF vs the 15uF?

There will be slight differences in the bass response, either will work nicely. 

[AllanMarcus]

Excellent ideas Paul. Thanks for the explanations.

What sort of celebration will you have on your 10,000th post? :-)

[Tom-s]

In my Mainline i went for Mundorf Supreme 10uf SGO's (because i thought they would just fit when i measured on pictures). These just did not fit, by 1mm or so. You can secure them a bit higher up in the amp with some zipties.
They were a bit too expensive not to try. They sound good.

[AllanMarcus]

In my Mainline i went for Mundorf Supreme 10uf SGO's (because i thought they would just fit when i measured on pictures). These just did not fit, by 1mm or so. You can secure them a bit higher up in the amp with some zipties.
They were a bit too expensive not to try. They sound good.

Interesting. Thanks.

These?
https://www.partsconnexion.com/MUNDORF-71366.html

a little too pricey for me, but good to know if these are 1mm too big, then 44mm should fit.

[Paul Birkeland]

What sort of celebration will you have on your 10,000th post? :-)

I hadn't noticed!

It's good to know the SGO caps don't fit. 

Mundorf isn't the only company making capacitors BTW, there are other choices.
https://www.partsconnexion.com/DYNACAP-64040.html
https://www.partsconnexion.com/JENSEN-78830.html
https://www.parts-express.com/jantzen-audio-10uf-400v-z-standard-capacitor--027-282
https://www.parts-express.com/audyn-cap-q4-10uf-400v-mkp-metalized-polypropylene-foil-crossover-capacitor--027-118
https://www.parts-express.com/audyn-cap-plus-10uf-800v-double-layer-mkp-metalized-polypropylene-foil-crossover-capacitor--027-141

Still, I could post 100 different high end caps that would fit, and a bunch of people will buy Mundorfs that don't fit and eventually do damage to their amplifiers.

[Alonzo]

Uhh, not just the Mundorf's that don't fit.  I went the beeswax route....

[Tom-s]

Insetting. Thanks.

These?
https://www.partsconnexion.com/MUNDORF-71366.html

a little too pricey for me, but good to know if these are 1mm too big, then 44mm should fit.

Can't say for sure 44mm will fit. Depends a bit on how you mount the output transformers.
You can move them around a bit on their rubber rings.
I see no reason to go for 15uf vs 10uf?

Edit: when on a budget.. K75-10 250v 10uf is a bit on the large side of things. But is a possible upgrade from standard caps/mundorf supremes.

[JamieMcC]

The 10uf  Audyn interlink Plus capacitors are a nice fit in the Mainline ;-)

[AllanMarcus]

The 10uf  Audyn interlink Plus capacitors are a nice fit in the Mainline ;-)

Do you mean this one?
https://www.parts-express.com/audyn-cap-plus-10uf-800v-double-layer-mkp-metalized-polypropylene-foil-crossover-capacitor--027-141

[JamieMcC]

Do you mean this one?
https://www.parts-express.com/audyn-cap-plus-10uf-800v-double-layer-mkp-metalized-polypropylene-foil-crossover-capacitor--027-141

Yes those ones in your link, I picked a used pair up off of ebay to try out in my Mainline for £15 the pair! Worth keeping an eye on used listings lots of interesting options turn up in the 8uf-15uf area for a fraction of the cost new. 


Will see if I can get to the amp to take a pick for you later.

[JamieMcC]

Ok found a pic, I have not cut the leads to size to permentently fit the Audyn caps as they have only been fitted temporarily otherwise I would have trimmed the leads shorter so the capacitors sat closer to the underside of the top plate  with a bit of Velcro added for further support. They do fit in the space nicely and their leads are pretty sturdy which helps when it comes to keeping the caps in place.

[AllanMarcus]

Ok found a pic, I have not cut the leads to size to permentently fit the Audyn caps as they have only been fitted temporarily otherwise I would have trimmed the leads shorter so the capacitors sat closer to the underside of the top plate  with a bit of Velcro added for further support. They do fit in the space nicely and their leads are pretty sturdy which helps when it comes to keeping the caps in place.

thanks for the picture. Very nice.

I may have missed it, but what effect do those caps have on the sound?

[Paul Birkeland]

I'd vote for the Audyn caps as well.  I've used them a bunch lately. 

[Deke609]

@PB: What is that in your second pic?  A monoblock tubeless amp?  With 2 power transformers?

Edit: mistook what I now assume is an OT for a PT. Assuming 1PT, 1 OT and 1 Choke, what's the other transformer?

[Paul Birkeland]

Power transformer, output transformer, plate choke, and power supply choke (not necessary at all, but the holes were already there).