Soundstage, layering and tube differences

you call burn in whatever you want

any electrical device, connection, circuit, will ’settle in’ over some time...whether it is seconds, minutes, hours, days... it has to do with physics of matter, electrical flow, heat/heat dissipation

w.r.t. tubes, they definitely have different sonic characteristics (frequency, amplitude, and phase differences)... not to mention your equipment interacting with the tube (driver and buffer circuits, components within those circuits), transformers, power supplies... each design/component operates as a system... nothing works in isolation

you call burn in whatever you want

any electrical device, connection, circuit, will ’settle in’ over some time...whether it is seconds, minutes, hours, days... it has to do with physics of matter, electrical flow, heat/heat dissipation

w.r.t. tubes, they definitely have different sonic characteristics (frequency, amplitude, and phase differences)... not to mention your equipment interacting with the tube (driver and buffer circuits, components within those circuits), transformers, power supplies... each design/component operates as a system... nothing works in isolation

Well said.

"Tubes need zero burn-in...zero." ????      Don’t know your opinion of Brent Jessee (one of the most respected names in NOS tubes), but- here are just a few sentences (verbatim), from a letter that he includes, when you receive tubes purchased from him: "New tubes need a break-in period before they can exhibit their true sonic character when used in audio circuits.      Preamp tubes especially benefit from a good break-in.      This period may vary widely, but NOS vintage tubes usually need at least 48 hours of use, sometimes up to 100 hours.      New current production tubes need 24-48 hours typically.      Good break-in can be accomplished by either leaving your tube unit turned on for 2 days in a no signal condition, or you can just enjoy the tubes for several hours each evening and they will be broken in after several weeks."        An opinion from another highly regarded (personally, at least) source: https://tctubes.com/power-tube-testing.aspx      Upscale burns theirs in for 72 hours, before testing: https://upscaleaudio.com/pages/test-equipment interesting:      https://www.youtube.com/watch?reload=9&v=jwmDf5bSRMQ

What kalali said, +1.