Will an Isolation Transformer Help My Digital?

The ARC CD3, at least in its first version, had a specified power consumption of 40W max. I would think it very unlikely that the power consumption of the Mkii version is much higher than that. The wall wart for the QuteHD DAC is described at the Chord site as:

12v 1A 2.1mm connector. Centre point positive 100V- 240V – 50/60Hz, 1A wall adapter supplied

I seriously doubt that it actually draws anything close to 1 amp at 120V (which would be approximately 120 watts) to be able to supply 1 amp at 12V (which would be approximately 12 watts). And the 1 amp output is presumably its max output rating, and what would be drawn by the DAC is undoubtedly a good deal less than that. And correspondingly the AC current drawn by the wall wart would be considerably less than it would draw when required to supply 1 amp at its output.

So it’s probably very safe to assume that the AC drawn by the DAC + CDP is less than 100 watts. A 500W transformer would therefore provide a margin of more than 5x, which certainly seems comfortable. Intuitively I would start to feel uncomfortable at less than 3x.

If you go to a linear supply for the DAC, though, before finalizing a selection be sure to assess its current draw or power consumption, as it will most likely be a good deal more than the wall wart’s.

One thing I don’t understand is why some iso xfmr’s are rated in watts and some are rated in amps.

Just a different way of specifying things. For a resistive load watts = volts x amps. So you’ll note that it says in the description of the Tripp-Lite Isolator:

Supports combined loads up to 500 watts continuous/4.2A at 120V.

4.2 amps x 120 volts = 504 volt-amps, which for a resistive load = 504 watts.

Best regards,
-- Al

Many thanks, Al. Your knowledge and the time you spend contributing to the forum is much appreciated.
Jim

A balanced transformer like the ones from Equitech can help. An isolation transformer is unlikely to help but you can try.

I have 6 dedicated lines. Does anyone make an Isolation transformer that I could use for each line. I would need 6 isolating transformers.

@jwm,
If you were to run your 6 dedicated lines to a subpanel and then to your outlets you could put one large 5 KVA isolation transformer in between your main panel and the subpanel.
Just something for you to think about.