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Old 30th November 2012, 09:10 PM   #61
LeonvB is offline LeonvB  Netherlands
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Quote:
Originally Posted by BrianDonegan View Post
AC Ground (Earth) SHOULD ALWAYS BE CONNECTED TO YOUR EQUIPMENT CHASSIS. ALWAYS. NO EXCEPTIONS.
I think that's not going to do anything unless your chassis is made of metal. And even with an aluminium chassis grounding the chassis entirely can be difficult when the parts are properly anodized.

Grounding or double insulated is the requirement for any appliance.
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Old 24th May 2013, 05:38 PM   #62
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to legato 3 common mode DC discussion. I built up my new B-IIIse and Legato 3 combo on some MDF for testing/tweaking purposes.

With the nCore 400 stereo amp, the Legato 3 needs caps: it will not work with either no pin 1 connection to G, or with pin 1 connected to G. Popped some 2.7 uF Mundorf zns in series with the output, and it plays fine with this amp. Too bad, I was really hoping the differential input of this amp woudl work without caps.

Pass Labs confirmed that my Pass X150.5 should be fine with the common mode offset, so I will give that a go next.
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Old 24th May 2013, 05:46 PM   #63
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to legato 3 common mode DC discussion. I built up my new B-IIIse and Legato 3 combo on some MDF for testing/tweaking purposes.

With the nCore 400 stereo amp, the Legato 3 needs caps: it will not work with either no pin 1 connection to G, or with pin 1 connected to G. Popped some 2.7 uF Mundorf zns in series with the output, and it plays fine with this amp. Too bad, I was really hoping the differential input of this amp woudl work without caps.

Pass Labs confirmed that my Pass X150.5 should be fine with the common mode offset, so I will give that a go next.
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Old 24th May 2013, 07:28 PM   #64
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for the double post, I had an internet glitch on my end.
Another data point: The Legato 3 works fine with the Pass Labs X150.5 with no coupling caps and the ground connected to pin 1. I suspect it will work fine with all the Pass Labs X and XA amps then, as they all seem to use the same input (voltage gain) stage.
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Old 24th May 2013, 11:50 PM   #65
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I have a dual mono BIII/single Legato build. Balanced out with ground disconnected would work fine with a Krell KSL pre amp, but not with the Krell KRC-HR. With the KSL I also had to turn volume down before changing source on pre amp or I'd get nasty pops through the speakers. I ended up reconnecting ground and using coupling caps. No more pops changing sources now.
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Old 24th May 2013, 11:54 PM   #66
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listening to the DAC with no coupling caps into the Pass, and then with some caps in place… I sure would like to avoid them.
Or… anyone have a recommended coupling cap which will not break the bank, I have used Mundorf Supreme, and it is good, but what is closest to no cap, still affordable (ie not Duelund VSF Copper) and reasonably sized...
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Old 25th May 2013, 12:13 AM   #67
sandyK is offline sandyK  Australia
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Hi Barrows
I once used 4.7uF Auricaps at the input to my Class A amplifier. They were markedly more transparent that ordinary 4.7uF polyprops that I bought from Jaycar, which appeared to give a false kind of soundstage.
The attached link will give you a general idea of their size and pricing .
They are also polarity conscious for best results.Something to do with the start and finish of the winding of the foil internally.
Kind Regards
Alex

Auricap
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Old 25th May 2013, 09:52 AM   #68
RollE2k is offline RollE2k  Sweden
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I would recommend ClarityCap MR for good neutral caps, they also don't cost THAT much - but they are quite big.. just look for them at PCX.
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Old 25th May 2013, 02:10 PM   #69
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Alex and Roll...

I see that Audience has the new version "XO" of the auracap, which is supposed to be improve on transparency. A nice thing about these is that they are available in a 200V model, which is quite compact as well.

I am considering the Clarity MR as well, so far everyone seems to like these for a transparent, "no cap" sound. It is not too big in 1 uF, about 25mmx40mm or so.

One "sonic signature" I would like to avoid is anything which enmphasizes high frequencies, or has a tendency to harshness or grain. I am not looking for added warmth, but I really do not want added coolness. This is a highly resolving solid state DAC after all.

It also appears that much of the "problems" associated with coupling caps may be caused by vibration. Since this is DIY, taking a little effort to make the caps more immune to vibrations might be a good step. I know the Clarity MRs address this through heroic construction details. Perhaps the Aura XO caps could be made into two cap modules, potted in a block of epoxy, and then mounted via sorbothane damping layers...
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Old 29th May 2013, 01:42 AM   #70
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Do not fear the caps.

I have had great luck with Solens and even Dayton's high grade caps.
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