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Tube upgrades for Jolida 502B?

I realize this is something that has come up before, though in searching the archives I didn't come away with a clear path forward. My amp is completely stock and came equipped with Sovtek 6550s. Using it to drive Totem Forest speakers. I contacted Jolida. They recommend KT88s. Their reply is a bit unclear but they might be suggesting Electro Harmonix. They also indicate reliability issues with Chinese KT88s. Response Audio (Jolida dealer and modder) recommends Shuguang KT88s (Chinese). The Tube Store recommended JJ Tesla KT88s on the strength of their great imaging and deep bass (more bass being something I was looking for). I was initially leaning towards SED Winged "C" 6550s. Now I am a bit more confused. I'm curious about KT88 vs 6550 sonics and reliability differences. Thanks in advance to any one willing to take the time to share their experience and preferences.
ghosthouse

Showing 6 responses by tbromgard

tbromgard
787 posts
 
Ghosthouse-
How do you like the sound of the Tube Store set of tubes? Are they reliable? How many hours do you have on them?

Im waiting for my first tube amp to arrive- JD 502 brc. Cheers.
tbromgard
787 posts
 
Thanks for the tips guys. Any other experiences tube rolling with the JD 502B?
tbromgard
787 posts
 
interesting-thanks
tbromgard
787 posts
 
Thanks for the responses. Now can anyone explain how to bias tubes in the 502brc? I dont have the owners manal
tbromgard
787 posts
 
Wolf Garcia-
I would think the 502b is the same. But do I understand correctly that you turn the screw until the led light comes on? I heard the opposite-that you turn the screw to the left until the led light goes off. Im not sure what to do. I put the tubes in turned it on and seems to operate great. sounds fine. none of the led lights are on...
tbromgard
787 posts
 
I decided to go with th following tubes:
Gold Lion KT88s. In the 12AT7 position, the Mullard CV4024. For the 12AX7s, Tungsram ECC83. All matched and designated "platnium." Get them this week. Cant wait to hear them. HOW LONG DO TUBES TAKE TO BREAK IN???
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