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Guidance for choosing step down transformer for audio gear

I am getting ready to move from the US to Switzerland (120v to 220v) and am putting together my plan for being able to use my current gear with the use of a step down transformer. Most of the details and information needed I have been able to pull off of manufacturer sites and other audio focused forums such as this one but have been unable to find a definitive answer on what wattage of a transformer should be used.

My gear list and max power consumption is listed below:

Amp - NAD M10 500w
Analog Source - Acoustic Signature Primus Turntable 22w
Phono Stage - Lehman Black Cube SE 3w
Speakers - GoldenEar Triton 2+ 1200w

I currently have all of my gear plugged into a Panamax MR4300 which I would like to continue to use for the additional protection and makes cable management a bit easier, (this is why I have the Primus, NAD, and Phono listed above even though you would find that they are 220v compatible if you checked). 

The total power consumption is an easy enough addition of 2,925 watts, where I run into my problem is picking what maximum watt rating for the stepdown transformer is best. I have seen posts that recommend everything from a max wattage to just over the total max power consumption summation to 2x the total all the way up to 6x the total power consumption number. This brings me to my main question of what is the best calculation to use for total gear being used and max wattage rating of the stepdown transformer?

Additionally, the Panamax is protected by a 15 amp fuse or 1800w max consumption (120v x 15 amp), since all of the gear above doesn't current trip the fuse what is the correct way to add up the total power consumption of a set up since I know the gear isn't using their max power draw at all times since that would be significantly over the spec of the 15 amp fuse in the Panamax and even the 20 amp breaker that the outlet pulls from.

Appreciate any guidance on this as I have been unable to find the answer through research.
gouldenear
gouldenear OP
3 posts
 
dannad,

thank you for the overview, the 2x rule for max power consumption is a figure I have seen quoted in other posts so with the gear listed in my original post the 2x factor for getting a transformer would be approx. 6000 watt capability.

dannad,

the spec listed on the back of the NAD is "100-120V~, 200-240V~, 50/60Hz, 500W" so I do believe that it is safe to use on the native power supplies both here and in Switzerland.

The limiting factor here I believe is the GoldenEars as they are rated only for 120v power supply (The 220v version is a separate class D amp) so using the Panamax with a transformer is more of a way to simplify where every thing is plugged into rather than needing multiple outlets and protector/conditioners.
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glupson
7,842 posts
 
the spec listed on the back of the NAD is "100-120V~, 200-240V~, 50/60Hz, 500W"

Owner’s manual mentions only different power cords with different plugs. It does not mention any switch to go between 110 and 220. Still, check it all around that there is none. (The way I learned about different voltages around the world and what that little 110/220 switch hiding in the battery compartment was for. It smelled like burned plastic.)
gouldenear OP
3 posts
 
glupson, 

Thank you for the thread recommendation, I had a chance to look though it and it has some very helpful links and comments even though it seems to start to get off track after a bit.
atmasphere's avatar
atmasphere
11,861 posts
 
If you are using an isolation/Step down transformer, if the transformer is loaded past about 50% of its capacity it will begin to make significant distortion on its output.

Its the 5th harmonic of the line frequency that becomes problematic- this harmonic causes power transformers to rattle, motors to have poor torque, diodes to radiate more noise. To avoid that you apply the 2x rule- it should not be tasked beyond 50% of its rated capacity.
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