Crate stealth with 2 6v6 and 2 6l6 tubes?

[mrmcsick]

acouple years ago I picked up a crate stealth 50 watt head and absolutely loved it. The first time I played through a stealth acouple yrs before that I thought they sounded like crap. After getting this one home I noticed it had 2 6l6 tubes in the middle power tube slots instead of all 4 6v6's? I ended up selling the amp a yr later due to money issues and miss it all the time. Never got it checked out to see if it had any other mods to it, wahhhh? So what would putting the 2 6l's in it actually do. This thing was freaking loud and super clean and responsive with the matching crate/celestion 4x12 I had. Played it many of times at practices almost all the way up with no reliabilty issues. Anybody help me understand what was done so I can get another one and do this to it?

Thanks.

[mrmcsick]

I saw on here after I searched crate stealth that someone actually did the same thing to theirs, putting just 2 6l's in the inner slots and leaving the outer 2 6v's. Im new to this and don't understand why just the 2 inner and not all 4, and what else if anything had to be done to the amp so this could be done?

[tubeswell]

Possible with the right combination of biasing, plate /screen voltages and load resistance. 6L6s run hotter, so its do-able to set the amp up (if it ain't set up that way already) to have a single 6L6 in place of a pair of 6V6s in parallel (which is what you do on each side of the PP output stage in this case), in situations where each side of the output stage's sockets are wired in parallel. do some searchs on the topic and you'll see what I mean.

[rockon1]

Thinking about trying this. The amp was designed for 6v6's. Four 6l6's would in all likelihood over tax the tranny right off the bat with too much heater draw.However only 2 6l6's wouldnt. Bob