[Dan Kolton]

I've gotten back my "R" upgraded power supply AVA equipment, and couldn't be more pleased.  I've had the 550EX, T7EC, and Transcendence D/A for some time, so I've had plenty of listening time.  The upgraded T7 and D/A came back a few days sooner than the 550, and the improvement was immediately discernable (some earlier upgrades had less obvious effect, and were hard to compare to the previous versions).

The most apparent improvement is that bass seems better controlled and tighter.  The lines of instruments and individual voice parts are more easily followed.  After the 550 came and was installed, I began also to notice a better image.  Whether the image improvement was there without the 550, I can't say, and I'm not interested enough to put my old AVA 150 back in to find out.

The one small quibble I have is that the 550 emitts a short hum during power-up.  According to Frank, it's the result of a part of the circuit coming up sooner than another, and isn't harmful.  He'll take care of it the next time my amp is in MN.

Bottom line: my 801s never sounded so good.

[Dan Kolton]

This is an additional comment on the same subject.  I did have the chance to put my old AVA Omega 3 - 200 power amp back in the system.  The improvement in image width, depth and specificity was remarkable when I returned to the 550.  I can't imagine why that wasn't obvious to me in the first place.  I also played a few vinyls - something I don't often do.  Wow!  That's a big improvement over the non-"R" components.  I might have to play vinyls more often and enjoy the more "Technicolor" sound just for laughs.

[John B]

Thanks for the report Dan.   I was over at my buddy's place this weekend to listen to my old rig, he bought my T7 & 350EX late last year.   It was sounding mighty good,  and we both wondered just how much improvement would be gained by him sending it all in for the R mod.   Seems it might be worth the downtime to do this by your reports.

[Dan Kolton]

 Seems it might be worth the downtime to do this by your reports.

I'd sure think so!

[Gary Buck]

I just got my T5R back.  Like you said, better bass detail and drive.  What really got me, besides the improved imaging, was the attack of acoustic instruments.  I was listening to some guitar and the notes jump out when
plucked harder.  It definetly feels more "live".  

It did sound a little grainy at first but, this quickly went away.  Maybe I got new tubes with my upgrade ?  

A real joy to listen to.  

I recommend the upgrade.  Very noticiable.