best output tubes for jolida 502b


I just purchased a jolida 502b. This will be my second tube amp. I bought a sophia electric baby but it didnt go loud enough,(I like to rock out sometimes). Anyway the output tubes I got with the 502 are the stock ones and they have some hrs on them. Does anyone have any advice on what tube to use when I replace them.
zeekzaak

I have the SED 'Winged C' KT88's in my AES Superamp and they are wonderful tubes. They're a different sound, which is what tube rolling is all about, but just as enjoyable to listen to as some of the more expensive NOS tubes I also have.
since the amp is new let the stock tubes stay in awhile to get used to the sound. my 502b came with stock eh 6550 and i later bought eh kt88. for the driver tubes i am using ge 6201 or mullard cv4024 in the 12at7 slots.
tungsol ecc803s in the 12ax7 slots. you can also sub 12au7 for 12ax7.