DB359 Preamp tubes

I just wanted to see what everyone had for preamp tubes in they're DB359's. I've had mine for a while and didn't use it that much because it would start to overdrive really early I couldn't get alot of volume out of it befor it started to break up alot. So I open her up and look around whoever had this amp befor had the pre amp tubes in the wrong place( a 12AU7 where the should be a 12AX7 and the 12AU7 where the 12AX7 should have been) so i swapped them back to where the should be and it made a big difference sounds great stays clean gets plenty loud enough at practice through my NV610. If ant body has any opinions on what tubes i should get for the preamp section let me know . I have already changed the power tubes and biased the amp