When voicing the Custom Designed and Built for myself Phonostage, all initial experiences was undertaken with a measured set of modern production tubes used as the constant.
Cap’s and Resistors were exchanged to see what was to be achieved for the voicing. After a selection of exchanges not cheap as tolerance across channels resulted in discards ( or more outlay to acquire components to test for closeness), the outcome was, a End Sound was developed that really was attractive to myself. The designer/builder also had a rethink on the component selection for their own model of the Phon’.
At a later time after a good few hours of usage, a tube rolling session occurred using a broad range of Valves from production era’s from the early 60’s to nearer the millennium year.
Valves used to roll were supplied with a near perfect matched A/B Half on each Valve and Paired Valves were almost measuring identical as well.
The learning had on the tube rolling occasions, was a substantial learning and a tube selected as a result of being loaned a broad valve range was a choice never considered to change. The prior to tube rolling voicing with components was equally beneficial to the End Sound that become available.
