Jeff Day's Positive Feedback Online Review: The Art of Vacuum Tubes: Sophia Electric 45 Mesh Plate Triodes and Aqua 274B Rectifier
"impression of the Emission Labs 45 mesh plates are that they don't really sound like vintage 45s. The Emission Labs 45 mesh plates sound richer and warmer than I remember any of my vintage 45s sounding, and well, I think they lean more towards the warmer and richer nature of a 300B. The Emission Labs 45 mesh plates are fine sounding vacuum tubes, to be sure, but I don't think they have the classic "45 sound" of vintage 45s.
"If you want new production 45s that more closely mirrors the vintage 45 sound, the Sophia Electric 45 mesh plates provide that. The Sophia Electric 45 mesh plates have that relaxed clarity, resolution of nuance, and vividness that I found so endearing about my vintage 45s. The Sophia's are more transparent, more resolving, more vivid, and yet are still very natural sounding in portraying musical performances. While the Sophia Electric 45 mesh plates more closely mirror the vintage 45 sound, they also have more extended and refined high- and low-frequencies, and if my recollections serve me well, an even more natural presentation of musical performances.
"The Sophia Electric Aqua 274B rectifiers remain my all-time favorite rectifiers for that same combination of clarity, resolving power, and naturalness that they share with the Sophia Electric 45 mesh plates. If you have an amplifier that will accept a 274B rectifier, I've found the Sophia Electric Aqua 274B rectifier an easy path to better performance."