HTM is a reference to mastering and cutting engineer Harry T. Moss, who worked for the EMI and Abbey Road Studios.
As a signature or mark of his work, Harry would etch his initials, "HTM," into the dead wax area of vinyl records. This etching served as a form of identification, allowing listeners and collectors to recognise his contributions to the mastering process. Harry Moss's work and his etched initials have become recognisable symbols within the vinyl community, often sought after by collectors as a sign of quality craftsmanship.
The HTM etching can be found on certain pressings of records like Revolver, Obscured By Clouds, and The Dark Side Of The Moon.
