[Amps] amp tubes

[carl s.]

   I have been working on an amp, fl2100B , and see something I can't 
believe.!!  the amp has 2 ea. New chinese type 572B's.
   I have two output meters, both WM1 auteks.;  With about 60-80 watts 
input I'm seeing almost 1 kw. *output*. Is this anywhere near logical 
??  The HV is about 2200-2300 under load. !! It just doesn't seem 
possible, and I've never seen anything like this
 before !!!
     I've worked on many other amps ( similar ) and have never seen 
anything like that much output.!!
     BUT, I've never used *chinese* 572'B s either !!
     Do any of you have any spec's that might differ from the
   U S. ( IE ) taylor ,l or other mfrs. Specs as to the gain factors 
between the US and chinese specs'?????>
     I'd appreciate any info anyone might have !!!!!
     carl / kz5ca