I would buy a matched set of 6h23neb tubes from the Tube Store and let them burn in for a day or so. I am using those tubes in my Modulus 3A preamp and it has been a revelation. The Sovtek 6922 tubes that Art Ferris previously used in your preamp are no longer of the same quality and can sound harsh and shrill.
Just got Audible Illusions L1, but it sound harsh
I just got a Audible Illusions L1 preamp to replace my Rotel RC 1070. I can hear it is much more detail, it sounds more forward and bigger sound stage. But I also found it too harsh. Especially in vocal, the "s" sound is very loud and quite alloying. I don't have it in my RC 1070, but at the same time, it doesn't sound as musical. It is just like sing behind a curtain. I don't hear that detail, but also, those annoying "s" sound is "filter" out. Is it a characteristic of this preamp? Is there any thing I can do? I am using a Rotel RB 1080 amp. Should I try another preamp? Or try another amp?