I believe Jenna offers a complete change in front-end, as well as wiring. The change may include conversion to mini-tubes in replacement of 6SN7s. I am also quite curious to learn of the sonic changes. I have a pair of MA2-Mk2s. I spoke to Jennifer at brief about the changes. She states they are not subtle. Brings the musicality to that reported of the Tenors. With the Atma-sphere already being so musical and alive sounding, a modification, without a demonstration scares me.