I dunno, I question whether this is really an accurate representation of the two tube types in the amp, you can def hear the different characteristic differences; however I think there needed to be volume leveling between the two types. Generally speaking 6L6's from my experience seem to have more low end, especially noticeable on cleans and that wasn't the case in this video, I always felt like the 6L6's were just more quite than anything else, and obviously had less of the upper mid spike. Either way both sounded good, El34's sounded a bit more pushed if anything.