A few quick questions, tried to search but i guess its hard to find specific information on this...figured i would just ask. My SVT blew a tube, i have no idea how but a tube did indeed crack. The tubes are sovteks and i have a few EHX tubes laying around...i did purchase a matched triplet of sovteks from thetubestore.com so i should just need to replace one section. 1. I noticed that in the ampeg svt cl manual, the bias knobs are described as handling the bias of the three left and the three right tubes. im assuming this is how the sections are divided, but i guess im asking for some clarification: the sections arent divided horizontally, but rather from left to right? Im a little confused as im wondering which tubes i would actually replace, and where the line of division occurs. (a visual aid would be incredibly helpful!) 2. i have a show in a few days, so in case my tubes arent here on time, the 5 remaining EXH tubes i have are matched and the 5 remaining sovtek tubes are matched (supposedly..see below) as well- though not to the EXH tubes...is it a bad idea to mix to brands if the sections are independent? 3. the sovteks i currently have are supposed to be matched, yet they still burn blue (i havent had them for that long) which gives me the impression the tubes still need to "burn in". HOWEVER, how can the tubes be matched if they havent burned in? im certainly no amp tech, so i apologize for any forehead slapping. anyhow, thats that. i thank you for your patience.