I don't know who does their mastering, however, like a lot of One Day's releases, a number of these tracks sound strangely muddy and lacking in crispness. Very odd, as many of the songs are commonly available on other CDs in pristine sound. Leroy Van Dyke's "AUCTIONEER' and Dodie Steven's "PINK SHOELACES' are not the 50s hit versions, but later 60s stereo remakes which both artists did later in their careers. (The originals were mono-only recordings). The old adage "You get what you pay for" certainly applies here. On the plus side, if you're not fussed about sound quality, there are some rarities here at a low price, including Roy Tann's 1957 rocker 'Hot Rod Queen' and Don & His Roses "Leave Those Cats Alone".