They’re arguably the best recordings Elvis ever made.

It would only be fair to expect that in the new historic box set, Decca Sound 55 Great Vocal Recitals, there would be a fair number of clunkers amongst the gold. But that is anything but the case. For just a bit more than $2 per CD, you will end up with so many superb performances, recorded by singers in their prime, that unless you already possess almost everything in the box—I do—or you require English translations for most of its contents, purchase is a no-brainer.

When Pass Labs is mentioned, it's natural to think of its founder, iconic engineer Nelson Pass. But Nelson heads a team of engineers at the California company: Their XP-30 preamplifier, which I enthusiastically reviewed in April 2013, was designed by Wayne Colburn; and the subject of this review, the HPA-1 headphone amplifier, is the first Pass Labs product designed by Jam Somasundram, former director of engineering for Cary Audio. Somasundram joined Pass Labs in July 2013; he spent a year working on the HPA-1, which was shown at the 2015 Consumer Electronics Show, in Las Vegas, but not formally launched until the 2016 CES, at a hefty $3500.