Autobiasing was done in early 50's. Everything in old and modern tube amps based on everything built and implemented 50 years ago the latest. VTL mostly manufactures the most primitive designs of pre-WW2 era, but few was made with autobias.
I'd say that Quicksilver amps are somewhat modern with semiconductor autobias circuit. Hybrids are cool too such as Counterpoint.
I'd say that Quicksilver amps are somewhat modern with semiconductor autobias circuit. Hybrids are cool too such as Counterpoint.