6AL11 is 1/2 audio out & 1/2 audio detector.
http://tubedata.milbert.com/sheets/127/6/6AL11.pdf
Bad part is most likely the detector if its a buzz.
Also if the out section were bad the hum wouldnt go away
with the VC turned down. As a rule hum= output
buzz=detector hiss=sound IF.
If its not the tube watch for open coils, the set must be getting
brittle & moving things can do it.
DO NOT tweak the coils !!!!
73 Zeno
