My go-to tube rectifier
In hifi use, this rectifier has NOS Mullard GZ34/5ar4 in all of my gear that is tube rectified. It neatly splits the difference between the euphonically forgiving-but-undisciplined sag of a 5u4, and the sometimes-too-tight-sphincter of a vintage 5ar4. In Melody Pure Black 101 and P7688 preamps, and in Quad II Jubilee power amps, I get burstier dynamics, deep bass finesse without bloat, best soundstaging and fluid musicality that exceeds any other rectifier I've used in the last 40 years. Also has proven durable. I also use it for tone and dynamic improvements in guitar amps where it fits.