Zesto vs K & K phono stages

David, although not all the upgrades in the current Maxed Out are officially supported for older units it is possible to do (with cavets). I was the owner of the very first complete phono pre kit sold. When I acquired a beta Venice I sold "Old #1" to a buddy and have kept him up with all the latest upgrades including a current source fed, shunt regulated B+ supply (this was an alpha test of the idea). I was floored by that change. So was Kevin. He felt, quite rightly, that this would be too difficult to migrate backwards to all previous K&K phono pre's. That said: if you happen to have one of the older units with separate L/R Chn. boards and separate PS board; there is room to do this. The maxed out with the PS and L/R channels all on one board just do not have the room. As for bettering the Maxed Out, unfortunately the Sonus Veritas Venice, Kevin's all out 3 stage fully differential, series feed, transformer coupled, $25K phono stage never really had a chance to be heard by very many vinyl fans which is too bad.
http://www.analogplanet.com/content/my-beta-venice-phono-pre
This is a photo of my beta Venice taken before adding a CCS fed shunt reg. to the input stage.

For the record, I had what is probably the latest K&K design since I got it around 2011. I agree, Kevin is a real pleasure to work with and very responsive to questions.

John, I must contact Kevin, it seems there may be new upgrades I could take advantage of. The last one must be 2 and a half years ago, which bought me close to the maxed out.

Vortrex, if your K&K phono experience is circa 2011, then no, it's not the latest design. The last three years have seen more that one upgrade.

Anyone owned a Herron and the newest K&K? How they compare?