Black Gates out, conductive polymer in...

[sharpi31]

I've had 2200uf caps in my Lite Dac-AH (passive mod) dac PSU for over a year. I have always been happy with the sound (a big improvement over the stock caps).

Today I received some NCC PSC 470uf caps (conductive polymer). I pulled out the two BGs and threw in two NCCs.

The two caps sound very different. I'd say that there is a bigger difference than changing teflon coupling caps for PIO. Initially the NCCs sounded less dynamic, had a tighter punchier mid bass and a crystal clear mid and top end. After an hour or so the dynamics seem to be coming back and the bottom end seems to be getting weightier.

Not sure which I prefer yet - the BGs were very rich and warm but not as transparent... I'm going to leave the NCCs in for a while and see what happens :-)

[sharpi31]

Since installing the dac with BGs, I have tweaked preamp tubes and coupling caps to get the best balance.

When I swapped in the NCCs the mid and top end became far more obvious. Not in a bad way - good recordings sounded good but poor recordings sounded edgy and unsettling. After a day or so I decided to look at my choice of tubes and coupling caps, hoping that I could retain the increased clarity of the NCCs while getting back some of the richness of the BGs.

I'd been using a Siemens silver plate preamp tubes and Jensen PIO coupling caps. This combo worked well as the tubes lifted the top end and the caps sweetened things nicely.

After swapping in Valvo tubes and russian teflon coupling caps I achieved a far better balance with the NCC caps. My system still highlights the differences between good and bad recordings in a way that it never did before, but the edginess has all but gone. Separation and focus from top to bottom are far improved.

Conclusions? Not easy given the number of variables but I'm more than happy that my system now sounds better than ever.

[Peter M.]

The difference in value of the caps is possibly more responsible for the difference in sound than the type of cap.

[sharpi31]

Great minds and all that....

I've just added another pair of NCCs in parallel with the first. The BGs were 1000uF (not 2200uF as I thought) so now the value is very close to what it was before.

Increase in solidity but the clear/open mid and top remain. The difference between the NCCs and the BGs hasn't diminished.

I've got a few of these spare (470uF 16V NCC PSC) so I'm happy to send a couple if someone wants to give them a go... No cost :-)

[sharpi31]

I've just replaced the cathode bypass cap (previously Nichicon) in my Hawthorne Spud amp with 2x 470uF 16V NCC polymer caps.

Again, the polymer caps have a far more open top end than the electrolytics. They sound more focused and extended but also smoother than the old caps. Detail is far better too.

Has anyone else tried these NCC conductive polymer caps?

[dweekie]

I'll join in so that you won't feel so lonely in here

I have one of those Spud amps and have been collecting parts to upgrade. I've been planning to use the Elna Silmics in that position, but maybe I will try out those NCC polymer caps instead. Let me see if I can find some to order.......

[dweekie]

Digikey carries them; I'll put them in my next order.

I'm a bit curious how they'll do around voltage regulators as stated in the datasheet.

http://www.chemi-con.com/files/PSC.pdf

[sharpi31]

Hi Dweekie,

Email me your address and I'll send you a few in the post.

[theAnonymous1]

Aren't these just OS-CONs with a different name?

Compared to Panasonic FM series of the same value they have 4.7x the ripple current rating. ESR is higher but that might just be due to fact it is measured at 300kHz vs. 100kHz for the FC.

[sharpi31]

I think the oscon SEP and SEPC caps are solid conductive polymer (the other ranges are older organic technology).

Most reports suggest that SEP and SEPC are way better than the older oscons.