2/90/2 4x12 12ax7 100 100 cl 100cl 2525s 2902 bad tubes bias blown amp board bogner cab cabinet clean clx combo d412 deliverance effects ehx el34 electro harmonix eminence eminence p50e fatbottom fja fryette gp3 gp3 preamp halfstack head hi gain honeyblonde hum jj's klein master volume memphis30 mesa mesa 2:90 vht 2/90/2 2902 parara pb45 peavey 6505+ pitbull pitbull clx pitbull fs ft pittbull pittbull 45 pittbull 45 head pittbull clx power tube preamp schematics sig:x sig x skb slave slaving solo switching tristan ultra-lead vht vht special six combo video wiring wtb wtb vht