I am just using the stock tubes that come with the Evo 400 preamps and amps. I have not noticed any sibilance, but I will keep your advice in mind if I do notice any.
I would love to hear the PL amps with better wire from the transformers to the power tubes. Now that would be one way PL could make a massive improvement in sound quality. In fact, it's the only way I can imagine these beautiful sounding amps being greatly improved. Van den Hul SCS-12 wire (or SCS-16 at a pinch) would do the trick! Please PrimaLuna?
I would love to hear the PL amps with better wire from the transformers to the power tubes. Now that would be one way PL could make a massive improvement in sound quality. In fact, it's the only way I can imagine these beautiful sounding amps being greatly improved. Van den Hul SCS-12 wire (or SCS-16 at a pinch) would do the trick! Please PrimaLuna?