SEX 10,000 uF 10V capacitor upgrade ...

[audiblesoundwave]

Hi everyone,

Does upgrading those Electrolytic Capacitors in SEX have any sonic improvement?  If it is, any brands and types should be consider?  Same or higher voltage? 

My apology if this has been discussed before!

Thanks,
Milton

[Paul Birkeland]

The single blue 10,000uif (10 or 16v, can't remember) electrolytic cap back by the power transformer won't matter too much. 

The big black electrolytics in the power supply are already quite expensive and fairly nice caps, but the other two radial leaded caps per channel can be upgraded with some positive sonic consequences. I think one is a 1000uf and one a 47uf.  I recommend increasing the voltage rating of the 1000uf cap from 35v to 50v (more easily facilitates switching to the 6EM7 in the future).

As for upgrades, I would look around at Digikey at Panasonic replacements.  I think I last used an FC radial for the 1000uf cap and an EE or ED radial for the 47uf cap (450v is desireable).
-Paul

[Grainger49]

A 30uF@630V Obbligato Polypropylene Film in Oil cap costs $19, a 70uF@630V Obbligato Polypropylene Film in Oil cap costs $29.  Shipping is a separate item.  A poster, NiceTom, tried them at my suggestion and loves them in his SEX amp.

Here is a link:

http://www.diyhifisupply.com/catalog/35

Again, no affiliation, just an appreciation of the product.

[audiblesoundwave]

Hi Grainger,

Are you suggesting to upgrade the 47uf Electrolytic capacitor to either the 30uf or the 70uf Obbligato Film Oil Caps?

Thanks,
Milton

[Grainger49]

Yes, downstream of the diodes, first capacitors and Rpsu, increasing the 47uF capacitor will be fine.  Dropping it to 30uf (1/3 less)  with a much better capacitor won't hurt.  But for the price the 70uf will be a deal!

[Paul Birkeland]

I suppose Rpsu could always be replaced with a power supply choke for each channel.  I wonder how the paralleled halves of the stock SEX choke might work for that duty...

[Grainger49]

Possibly a Hammond 154G, 9H, 700 ohms, 300mA?  I'm just looking at the specs.

[Paul Birkeland]

That choke would work, but seeing 9H at 300ma makes me think it would be a huge choke.  Other than using the stock plate chokes (which should work just fine), as would the Hammond 155G, 156G, and 157G.  The 155H, 156H, and 157H would probably work fine too.  You will have a little extra B+, but not too much.