winged c 6550c is not good for ref 5se??

I cannot speak for Upscale Audio but recently Wing C has had quality issues due to damage to their plant.

I bought a couple of hundred matched Wing C a few years ago and used them in my VTL amps. It provided the best sound and remains my favorite 6550 of all time, without exception.

Check with Upscale and see what's going on and what they suggest. Their testing procedures are excellent and they guarantee their tubes.

Kevin Deal is a pretty honest guy. If he declined to ship the Winged Cs, he had a good reason.

Kevin also sells the 6550 WE, which is the tube ARC is currently uses in the power supply of its Ref 5 SE linestage and other input products.

I was surprised that the Tong Sol 6550 sounded pretty good too.

Brandon-

go w/ these guys' advice. The REF5 SE is a very special piece of gear, you do not want to alter its sound/ability to deliver pure listening pleasure. Keep us posted on your tube selection. Happy Listening!