KT88 vs EL34 vs 6L6 Substitution In Vacuum Tube Amplifier.wmv

This video was inspired by a question I was asked about swapping KT88's in place of EL34/6CA7's. I have used a couple of amps in the video and made cathode current and power output measurements on three types of tubes -- 6L6GC, KT88 and EL34. This video is not meant to encourage anyone to swap the output tubes in their amplifier out for other types but in the case of musicians, I know they are always looking for a unique sound that they may be able to get through vacuum tube substitution. Remember also, swapping around the 12AX7, with a 12AU7 or 12AT7, etc. may also change the sound and no over current conditions are going to exist with these tubes. In rare cases I have seen instabilities introduced by substituting these tubes resulting in oscillations. In any case, I hope the video does provide some (safe) ideas on tube substitution and helps prevent destruction of equipment.