Groove Tubes Gold Series GT 6V6-R Matched Power Tubes Medium (4-7 GT Rating) Duet

Bought these just before the Russian sanctions. My tech said these tubes almost took out my vintage 1965 Princeton's output transformer, due to arcing. I guess Groove Tube has gone to the dogs like the rest of the world. Not a fan of solid state amps but I think I will use my Mustang II until the tube situation settles down. Seems the embargo has given manufacturers permission to sell the subpar tubes that were in the junk pile. No thanks.

I got the tubes and one broke while installing it. Customer service said I would have to pay for a new set or go to a local Guitar Center to dispute it. I took the one good tube left, put it in with the tube that wasn't burnt out, and it works/sounds good for now. Musician's Friend, Sweetwater seem to have better online service. I won't deal with GC again unless it's in the store

Luckily the tubes were ok. When I opened the box, the interior box with the Groove tubes (manufacturer package) was not well packed. The tubes were hitting each other when I opened the package. They broke loose from their cradles and were not well packaged. Seems to me that whoever packed the box for shipment would have ensured that they weren't able to come loose from the manufacturer's packaging. I know this was not intentional, but recommend next time that the product is packed well within Groove Tube's packaging before adding more packing to the box it was shipped in. That is my only issue -- other than that I am satisfied with the tubes themselves.

I have a 1968 fender deluxe reverb that had an off brand set of output tubes i think they were called nationals. They were pretty bad i put this set of tubes in and could not beleive the difference.i really like the tone

Put these in my Egnator Rebel 20 head. They sound great. Nice break up when overdriven.

My first order had a damaged tube. The tube was cracked after i opened it up in guitar center's parking lot. They took the tube's back right away and ordered me a new set. They even gave me a card to a shop that can bias my amp. i got the valves the following week. Im writing this review much later and GC if your reading this you did me a solid! Thanks. -Darin M. Yuhas.