using a transformer to separate your gear power

I have a 1KVA low-tech coil isolation transformer, weighted 35 lbs.

My experience is that the IT does expand the soundstage and helps the seperation of instrument. The bass can reach lower and highs are significantly smoother on my system. The overall sound is certainly clean and pleasant.

The only drawback I found on traditional IT is the slow response. When I watch those booming movies such as "Pearl Harbor" , I notice the bomb's full explosion was just a bit staggered than usually. This may be due to the fact that the transformer need a bit more time to 'transform' large power from the input to the output.

My amp consumes about 400W and the 1kVA transformer should be well beyond the amp's quest for power, but it does not seem that way.

Now I unplug the IT when I watch movies and put it back when I listen to strings and vocals.

Isolation transformers should have a 20:1 ratio to work properly which is why we generally recommend them for digital components, televisions or pre's. As an example your IT should be rated at 8kVA to avoid transformer saturation. I may be in overkill mode but, better safe than losing dynamics.

Jc, how did you arrive at the ratio that you posted ? As to being "overkill", i like that : ) Sean
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JC is right to a large degree. With most transformers the inductive process (which is how the transformer works) also works against it. It can, if not designed properly, limit the current flow. This is a big deal in x-ray devices as they require HUGE amounts of current flow on demand, and they are always pushed right at their limit. If it's a 6.5 KVA unit, you can bet the demands are at least 6 KVA. Many of the transformers that we find in some products are off the shelf transformers that really don't serve audio very well--particularly amplifiers, which is why so many amplifiers sound better not connected through an isolation transformer (power conditioner).

As to a 20:1 ratio--I don't know about that, but I would definitely agree with an abosulte minimum of 5:1 for amplifiers unless it was really designed to deliver the current on demand.