half-speed mastering

{{Short description|Phonograph record production technique}}

Half-speed mastering is a technique occasionally used when cutting the acetate lacquers from which phonograph records are produced. The cutting machine platter is run at half of the usual speed (16 {{frac|2|3}} rpm for LP record) while the signal to be recorded is fed to the cutting head at half of its regular playback speed.{{cite web|url=https://sonicscoop.com/2018/12/22/half-speed-mastering-explained/ |title=Half-Speed Mastering Explained |publisher=sonicscoop.com |date=December 22, 2018 |first=Charles |last=Hoffman |accessdate=2021-02-19}} ^{{{Dead link|date=March 2023}}}

The reasons for using this technique vary, but it is generally used for improving the high-frequency response of the finished record.{{Cite web|title=All You Need To Know about Half Speed Mastering {{!}} uDiscover|url=https://www.udiscovermusic.com/halfspeed/|access-date=2021-08-13|website=uDiscover Music|language=en-US}} By halving the speed during cutting, very high frequencies that are difficult to cut become much easier to cut since they are now mid-range frequencies.{{cite web |url=https://www.yoursoundmatters.com/what-is-half-speed-mastering/ |title= What is Half-Speed Mastering?|last=Henshall |first=Marc |date=May 7, 2019 |website=www.yoursoundmatters.com|access-date=2021-02-19}}

Mobile Fidelity Sound Lab used half-speed mastering for its Original Master Recording LP's.