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Will an Isolation Transformer Help My Digital?

I am experiencing noise from my digital components into my system. It presents as high frequency interference thru the speakers once the components are warmed up. This interference is being sent back to the mains and can be heard when music is being played or idle.

I’m using an ARC CD3 mk II CDP, Chord DAC, and a NAD CD player. I have a 20 amp dedicated line with Blue Circle power conditioning at the wall.
A Furman power strip for the low-current analogue components is plugged into the PC. Also feeding from the PC is a Tripp-Lite Isobar with isolated filter banks for the digital. The toroidal chokes in this Tripp-Lite power strip are not able to filter the digital noise.
My amp plugs into the wall duplex outlet.

I posted a thread earlier where it was mentioned than an isolation transformer used exclusively for the digital components might resolve the noise/interference problem.
I read in the archives about the use of a Tripp Lite IS250HG Isolation Transformer to isolate the CDP/DAC.

https://www.amazon.com/dp/B0000ET7Q6/ref=wl_it_dp_o_pC_nS_img?_encoding=UTF8&colid=29XG41GAZ363K...

So, I’m asking if this would be a solution, since I don’t plan on running another dedicated line. (too many reasons to list).
128x128lowrider57
lowrider57's avatar
lowrider57 OP
5,417 posts
 
@ptss, thanks!
What size would you recommend for use with an ARC CD and a small DAC? I have seen xfmr's rated in watts; shouldn't they be rated in amps?

Also, is this Topaz good enough for high-end audio?
http://www.ebay.com/itm/191842008876?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
lak's avatar
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lak
4,629 posts
 
Lowrider57,
Just remember that if your isolation transformer is going to be located in your listening room, it will generate some heat and some noise (hum).
For example, my isolation transformer does run warm to the touch (96 degrees F and produce 55 dB of sound with the reading taken within one inch of the transformers). The noise and generated heat doesn't bother me because the power filtration system is located in a different room.
Depending on the size of the isolation transformer, the heat and noise level will vary, however you never know what’s going to happen (noise, heat and filtration wise) until you try it.
lak's avatar
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lak
4,629 posts
 
I think the Topaz isolation transformer you refer to above would work for your ARC CDP and small draw DAC.

ptss
1,964 posts
 
Test some units of different amperage on just your digital. But remember, each unit improves as it's power supply is improved,so the testing should be repeated for your digital after you've improved the PS to the other units. The sound will go up and up and up. Cheers to a pristine source of AC.
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almarg
9,670 posts
 
Lak makes a good point about acoustic noise being a potential concern with the Topaz isolation transformer or other comparable devices. I couldn’t find meaningful data on the Topaz model 91095-22 linked to above, but I found this datasheet covering the model 91095-32T, among others, which appears likely to be fairly similar. The spec listed for acoustic noise is "less than 50 db measured at 3 feet from the noise suppressor." Ouch, unless "less than" is actually "a lot less than."

I also note, btw, that the particular listing for the 91095-22 indicates "open box," perhaps indicating that the device was previously purchased and then returned, or was obtained by the seller from a previous user. And in fact despite the indication of "unused" in the listing the power cord pretty clearly shows signs of use, and even a bit of damage, when the photo in which it appears is expanded.

Best regards,
--Al

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