I got 2 Elgar 6006B units. The first unit is from 1973 and the second unit is from 1984.
The first was dead on arrival because it was severely damaged during shipping, so I bought the second one. After a lot of tinkering, I was able to get the first one to turn on and finally got the fan to run. Both meters are inoperable and I would never plug a component into it. But I at least got a sense for how loud the fan and transformer are. The older unit’s captive power cord is only 4 feet long, while the newer unit’s cord is 2m.
The newer unit is a lot quieter than the older unit -- both the fan and the transformer are quieter. So newer is better, but still loud. I modified the newer unit to include a switch to turn the fan on and off. Using a handheld SPL meter, the transformer alone is 60dB at 0.5 inches from the front grill. With the fan on, the unit puts out 67 dB at 0.5 inches from the front grill.
So I don’t recommend using this unit with the fan on in your listening room. With the fan off, it’s a judgment call. I put the unit in my closed cabinet and could still hear some transformer hum. This would be a non-starter for most people. Once the music starts, I generally don’t notice the hum, but it’s there during very quiet passages.
I did a comparison between: 1) Nordost Thor only, 2) Elgar only, and 3) Thor plugged into the Elgar. I had my kids participate to get a reality check. We all agreed that the Elgar by itself was clearly better than the Thor by itself. And Thor plugged into the Elgar was even better, but very very close to just the Elgar by itself. Having the Elgar in the system provided better resolution, more shimmering highs and tighter bass, a sense of more energy, and more PRAT. Adding the Thor to this enhanced the energy and PRAT just a tiny bit. After taking the Elgar out, the sound seemed flatter and less "fun" and the bass was flabbier. For these tests, I used Eva Cassidy’s Bridge Over Troubled Waters because there is a lot of tape hiss in the recording. With the changing of components, we could clearly hear more and more tape hiss (better resolution) as we moved from Thor to Elgar to Thor+Elgar.
I also plugged my HT processor and 4K player into the Thor+Elgar to watch a movie and the HT side has never sounded better.
With the fan off, the unit was only slightly warm to the touch after a 2 hour movie (preamp, HT processor, and 4K player were plugged in and using a total of only around 1 amp on the meter.)
So, in short, I really like this unit - it makes a clearly noticeable improvement - but it’s probably too loud to be a keeper. I recommend this unit if you can place it outside your listening room (such as at the breaker panel or behind a wall where your equipment might be remotely located.)
I’ll keep it for now, but would like to find something new that’s exactly like this unit without the transformer hum. Frankly, I’m doubtful that I’ll find something that’s this good in an all-in-one box that I can place on an equipment rack. I’ve had a few other units in the past and nothing has been this good. I may explore the option of putting the bigger Elgar 3006B unit at my breaker box.