Is an isolation transformer better than a power conditioner?

It improves the SQ but not dramatically. And it is two large chassis that take up a lot of real estate. And not particularly attractive. And we’re $18K new! One would expect transformative performance."

You spent $18K, and yet...

Testimony for the curious-yes, it all MADNESS!

I am a very firm proponent for balanced AC electrical power for audio components.

Me too!

That’s one of the reasons why I run all my audio gear on 250 volts, its balanced voltage not needing a neutral or balanced load. Also, the sound quality is better, and it negates the need for a balanced AC PC/isolation transformer. That’s been my experience with North American voltage (USA). FWIW: Because the amp is now running at twice the voltage but half the amps (current) the wall wiring looks twice as thick to the amp as it does at 120 volt (ohms law). Now the amp makes even less audio noise on the line and it then rejects its own line noise better. The 220 volt outlet can be a standard 15 or 20 amp with 12 Ga wire.

Mike

I found that the hum from my larger isolation transformer, in the same room as the equipment, was too loud to tolerate.   They all hum and imho a large one must be located outside near the box.  I agree the improvement is slight.

For years I had hum, incoming voltage running between 123-126v in those years. Since repairs, 119-120v 24/7, no perceptible hum ever. Over voltages and dc offset  usual causes of transformer hum. Mounting them properly very important as well.

“Is an isolation transformer better than a power conditioner?”

In my experience, Yes! I had some highly rated power conditioners through my system (Audience, Nordost and Shunyata) and they all added some sort of coloration. AQ Niagara 7000 was the worst offender, dump it after 30 days trial (strangely dealer was in hurry to take it back).

I am currently using a isolation transformer and it’s dead quiet, no hum whatsoever!