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Old 24th June 2005, 08:59 AM   #11
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Ok, here goes.

I've got the caps, RCA's and binding posts in my hot little hands. The transformers I've ordered and the case I've begun gutting and modifying for the new amp.

The caps I went for are Nichicon KG Super-throughs 50V 10000uF, a total of 4 or 2 per module. I got them stupidly cheap, and they are very good so I will see how they go. Thing is, even if I decide to change, I can always do something else with them. The only thing wrong with them is their physical size, but it's something I can accomodate.

The RCA's are Vampire ones, with some Cardas binding posts, so I just need to sort out the new back panels. The transformer I went for was a 30V 160VA as recommended

Now, I have a pair of these lying around:
http://www1.jaycar.com.au/productVie...Max=&SUBCATID=
Problem is, while they do fit, it would be a lot easier if they weren't so big. My case is an old tuner one, and consists of a ventilated base, with a closed top. Given that the amp will never be enclosed in a cabinet, would it be okay to cut said heatsink in half and use half to cool each UcD180 module?

Cheers,
Nathan
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Old 24th June 2005, 09:07 AM   #12
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One-sixth of this heat sink for each module is fine.
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Old 24th June 2005, 09:19 AM   #13
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Haha I just wasn't sure with the partially enclosed case, half it is then, works out fine because half is only a little bit longer than the module itself.

Thanks for that Bruno.
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Old 27th June 2005, 10:17 PM   #14
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Default Two questions for Bruno:

Quote: Use "slit foil" caps (available only as 10000uF so that answers that question).
>http://www.dnm.co.uk/capacitors.html>

1) are you recommending us to use T-network caps? If so, a diagram with connections will be needed.

2) aren't all pricier BHC big can caps made with "slit foil" configuration?

I've searched at BHC's site and couldn't find the info.
I buy at RS-export and they only carry ALS30-31 ALS 40-41.

Many thanks

Mauricio
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Old 28th June 2005, 06:40 AM   #15
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Default Re: Two questions for Bruno:

Quote:
Originally posted by maxlorenz
1) are you recommending us to use T-network caps? If so, a diagram with connections will be needed.
Although they are clearly technically better, I don't find the improvement of the T networks significant in listening tests.
Quote:
Originally posted by maxlorenz
2) aren't all pricier BHC big can caps made with "slit foil" configuration?
No. Slit-foil is only used on the caps made for DNM. It should not stop you from trying the standard ones out as well. Often different electrolytics made in the same factory sound quite similar.
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Old 28th June 2005, 10:15 AM   #16
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Yay! Modules arrived. Two more questions.

I've always been told that a soldered connection is always going to be better than a "press fit" (?). Is it okay to solder the connections directly to the spade terminals?

Also, which ones are the input coupling caps on the new UcD180 modules?
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Old 28th June 2005, 11:12 AM   #17
Pasi P is offline Pasi P  Finland
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Default Re: Re: Two questions for Bruno:

Quote:
Originally posted by Bruno Putzeys

Although they are clearly technically better, I don't find the improvement of the T networks significant in listening tests.

I have ordered T-network caps to see how they perform anyway.

One minor question. Do T-network caps need any special attention to power supply. Only separate inputs and outputs as descriped in BHC documentation?
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Old 28th June 2005, 11:31 AM   #18
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Default Re: Re: Re: Two questions for Bruno:

Quote:
Originally posted by Pasi P
One minor question. Do T-network caps need any special attention to power supply. Only separate inputs and outputs as descriped in BHC documentation?
You have to use separate secondaries and separate bridge rectifiers per power supply side to get the best from them (so you only join the grounds at the "outputs" of the T caps).
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Old 28th June 2005, 03:34 PM   #19
Pasi P is offline Pasi P  Finland
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Default Re: Re: Re: Re: Two questions for Bruno:

Quote:
Originally posted by Bruno Putzeys


You have to use separate secondaries and separate bridge rectifiers per power supply side to get the best from them (so you only join the grounds at the "outputs" of the T caps).
Sorry, i did not exacly understand.
I thought it as in picture attached, but do i have to connect GND(IN) and GND(OUT) together?

(sorry about bad picture )
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File Type: jpg ucd power supply2.jpg (69.2 KB, 740 views)
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Old 28th June 2005, 03:46 PM   #20
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Almost OK. This is what I meant:
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File Type: jpg ucd power supply3.jpg (59.0 KB, 834 views)
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