[Wood]

You will need to add the larger decoupling caps. Best to remove the 10uf large SMD tants and put them there.
 
Those caps are ok, but you can get away with anything 2.2uf (smaller size is useful here) and above. MKP is usually preferred to MKT, but they are both good, try Bennic, Mundorf m-cap that kind of thing, some people have used Dueland!! Yes they are located at the top of the floating board.

 

[LosNir]

Can I get a few pictures? Thanks.
 
I have a pair of WIMA MKP10 Polypropylene Film 2.2uF/250V. Will this do the work well?
 
By the way, are the DC 30 Power Supply Caps really Panasonic FM? They look like cheapish 470uf. I replaced all of them (470uFx10) with real Panasonic FM 2200uF (x6).
I also took out the tantalum 0.1uF Filters and replaced them with WIMA MKS4 0.1uF and soldered them under the board (shortest path).

 

[Wood]

The wima will be an improvement over the tants, personally I don't like wimas in this position, and believe you could do better in a similar price range, I would even prefer those ero.
 
Nice call on the DC 30, reminds me I have to get round to that myself.

 

[marcelnl]

I would also not underestimate the DIR 9001 mod...

 

[LosNir]

Can you eloborate? Thanks.
 
I also wired up the 7.5v Rail within the Valab itself to the switch. So now when the power is on, the power led goes on, but the usb is still off until I turn the switch to "On".
 
 
Quote:

The wima will be an improvement over the tants, personally I don't like wimas in this position, and believe you could do better in a similar price range, I would even prefer those ero.

 
I thought I'd use the Wima's (MKP10) 2.2uF for the coupling caps.
 
 
Quote:

Originally Posted by Wood 
 
Nice call on the DC 30, reminds me I have to get round to that myself.

 
Thanks.

 

[Wood]

I think you were right to query the make of the caps in the DC30. I just replaced them. Those caps seem very light, in weight, and the print is bad quality, the gold has more red in it then the Panasonic trade gold.
 
I put in 2 Black Gate FK 1000uf  50v, one for each output supply. They are not burnt in and the total uf is smaller, 10,000 to 2000 so it is prob my imagination, but... I am sure the bass is tighter and the overall sound is more dynamic. But I would expect improvement with Black Gate FK anyway.
 
Bit tricky re-seating that transformer, but worth it.
 
Yes I mean the coupling caps too, I think the original are tants.

 

[LosNir]

Yup, it's a real nightmare resetting the R Core Transformer - An easier way is to cut off all plastic handcuffs so it easier to have access to the nuts. Then put new cuffs of course.
 
The original coupling caps are oil, doesn't it? I'm attaching a photo to point to what part I'm talking about:
 

 
This is my WIMA MKP10. Should be used to replace the ones which I bordered red (10uF)?
 

 
And here are some mods I did:
 

 

 

 

[marcelnl]

the caps you circled in yellow are the digital input caps, one for USB and one for the Spdif input.
I ripped out the in and output caps completely as my power amp has a coupling cap and I like tp live life danerously as far as the input signal goes.....what is better than a good cap....no cap
Personally I like the WIMAs and the EROs, but with a bit of tinkering you should be able to come to a much better alternative at low cost...just scrounge for NOS caps..give the russian teflons that are flooding ebay a go or try some good paper in oils (that is if closing the lid is not required)
 

 

[LosNir]

 
Quote:

the caps you circled in yellow are the digital input caps, one for USB and one for the Spdif input.
 

You mean Spdif and Coaxial, right?
 
Thanks for your reply. I replaced the caps with the Wima MKP10 2.2uF.
 
First of all, what is the difference of using 2.2uF instead of the original 10uF?
 
Second, if the Russian Teflons won't perform any better than the current Wima than I leave the Wima as it is.
 
Third, I'm attaching some more photos to reflect the changes I did:
 

 

 
1. As you can see I changed the coupling caps to Wima.
2. It's hard to notice, but I changed the power switch route to a shorter one, and I used a thicker cable as the previous one was very thin and probably won't handle high current - Just to be sure.
 
Can you please point out a possible mistakes I did? As you see I'm test-running it while it's open - and I don't want to assemble everything than find out I need to fix something
 
Thanks again.

 

[Wood]

Your board looks different to mine.

 

[LosNir]

It is unmodded?

 

[Wood]

Unmodded, however this is from the very first batch of DC30-W.

 

[LosNir]

Looks like I got a newer version then.
Well, I finished everything - It's closed now and doing some break-in

 

[marcelnl]

the russian teflons will be dfferent, hard to tell what you"ll like more....
2.2 uF may be limiting the bottom end of the freq range, but not in case your amp has a high enough input resistance.
If you come close enough to the freq range teh 2.2 uF will et through you may experience some phase problems, with 10uF the bottom end is so low that this will likely never happen.

 

[LosNir]

What frequnecy could that be? Under 30hz?