[quote name='strtdv' timestamp='1418371344' post='2629564']
Yes, they're cathode biased so you can change the valves without biasing.
It's not actually true class a, just very hot class ab.
The Lionheart range are the only amps they make that could be described as true class a.
To be honest, even in a fixed biased class ab, biasing is less of an issue than you think, it's unlikely to damage the amp in any way unless you run something that's way out of range like a kt77 in an el34 amp.
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Thanks again bu no further action due to valves in Brighton and amp in Liverpool.