by keithmantle » 29 Feb 2012, 17:21
According to Billm the std 12AY7 or 5171 can be used in the P/i position, The E/Harmx EL84's are balanced, I did try it as you advised with just 1 AY7 in V1 but i couldn't really say there was much difference (deafness has this effect) so will have to wait for next hankies meet for good ears to comment !!. It also states half the gain (AY7) valves does not mean half the volume, just that distortion doesn't kick in until much higher vol, ie level 8 AY7 level 4 AX7