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wtfaidh 21st March 2009 06:37 PM


Originally posted by bro
I prefer small amps so that I can chuck them around in my small apartment. :)

I am afraid that my primary transformers (42V-0/0-42V, 1000 Watt) will not fit in a tihgt case... ;-)

Using a "Airport Express" for conveniance is a fine choise (I am using a SqueezeBox Myself),

But if you want to hear the NCD's sing : use a conventional CD player...!!!

Cheers, Eric.

bro 22nd March 2009 05:29 AM


Originally posted by wtfaidh

42V-0/0-42V, 1000 Watt

Does it hum? I could hear mine when I put my ear next to it. Would potting the center help?

I tend to agree on the CD player. Need to get a preamp to hook up my sacd player. :) hmm, more projects!


cdl 19th July 2009 04:13 PM

Status on EMC
I posted previously about my EMC problems in relation to DAB reception (and probably FM as well, but I don't use that currently). The problem with DAB is intermittent (mostly at sunrise and -set, and especially strong just after turning on the amp, tends to decrease when the amp has been on for a while). I also noticed that having a D-Link USB WAN adapter close to a speaker cable caused significant bandwidth deterioration (even with EMC kit), but moving it 1m away from the speaker cable solved the problem.

First test with the EMC kit was promising, but with long speaker cables attached, the problem was back, although less severe.
The other day I finally attached my new speaker cables (3m x4 for biwiring), which seems to further reduce the problem a bit, but it's still noticeable :-/

On the brigth side, reception is tolerable now. The following 4 things have reduced the EMC:

1) Moved DAB antenna away from the amp connecting it through some 4m of shielded cable. Carefully separated "noisy" speaker cables from the antenna cable in the "snake garden" behind the hifi (speaker cables go right, antenna goes to the left). Attached clamp-on ferrites to the shielded cable at the antenna connector on the tuner (doesn't seem to limit signal strength)
2) Mounted EMC kit and clamp-on ferrites chokes on all power cables.
3) Replaced long speaker cables (4x7m) with shorter ones (4x3m)

The only further thing I can think of would be to attach some 0.1F caps in series with the speakers at the terminals on the amp (yes I know this might affect the treble). Will try this once I come across the ones I have lying around somewhere, I guess i'll just connect them to some banana connectors and try plugging them in to see if it helps. :rolleyes:

Otherwise I am out of ideas. So Lars, you are most welcome with your spectrum analyzer any time ;)


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