Groove Tubes Gold Series GT-6550-C Matched Power Tubes
I have a system >> Pre Amp Audio Research REF-5 >> Power Amp Audio Research REF-210. One of the my power amp's tube is broken. I need to change it but I am looking forward to upgrade these tubes all. Currently, REF-210 has 4 Groove Tubes Gold Series GT-6550-C Matched Power Tubes on it. I will change 8 of them for two power amp. Do you have any suggestion for tube models/brands would be better than GT-6550C.
Thank You !