@atmasphere
Most of the reputable tube dealers manually tested each NOS tube for low microphonics, low noise etc. Lucky people knows the difference between new and nos when it comes to the great tubes. I bet you have some decent NOS tubes yourself.
Anyway it's a good news that your or herron preamps works great with stock new tubes.
BTW i really like the design of Atma-Sphere MP-1 and MP-3
Yes- new tubes. We don't recommend NOS tubes for either the output tubes or the phono tubes. In the case of the latter, its just too hard to find NOS tubes that are actually in fact quiet- those were sold off the shelves decades ago and all that are left now are the dregs unless someone got extremely lucky. So we don't recommend NOS tubes for our phono sections- we encourage people to use new tubes if they want the best noise floor and lowest microphonics.
Most of the reputable tube dealers manually tested each NOS tube for low microphonics, low noise etc. Lucky people knows the difference between new and nos when it comes to the great tubes. I bet you have some decent NOS tubes yourself.
Anyway it's a good news that your or herron preamps works great with stock new tubes.
BTW i really like the design of Atma-Sphere MP-1 and MP-3