Hi, I got a nice VBA400 with some nice 6550c svetlana valves, sounds awesome but can I take it any further? preamps havent been touched. Thanks in advance
I just got one too. Liking the Svets in there. I swapped in some NOS RCA and Mullard 12ax7s, and replaced the stock (whatever it was) 12au7 with a NOS Sylvania. The amp already sounded really good, but the tube change definitely woke things up. It sounds like thunder!
Yep a pre amp tube replacement on the VBA can really make this amp a fat snarling beast (even more so).
FYI the stock 12ax/au7's are Sovtek rebranded with Marshall.
I too replaced mine with NOS Sylvania 12ax7(Baldwin organ) for v1-v3 and a NOS RCA Blackplate for the 12au7 in v4.
I just love it - tubey, growly goodness.
My Power tubes are still the stock Marshall/Sovteks as Ifeel they make less of a difference to tone, however when they die Ill probably put some winged C's in.
Either way have some fun playing around with tube pres. It can get expensive if you follow up every piece of advice (depending on what sound you are after), however I found that most of the online tube retailers to be quite straight forwards and clear about tube suggestions.
