![]() Reducing the low frequencies also limits the excursions the cutter needs to make when cutting a groove. ![]() The net result is a flat frequency response, but with attenuation of high-frequency noise such as hiss and clicks that arise from the recording medium. A recording is made with the low frequencies reduced and the high frequencies boosted, and on playback, the opposite occurs. RIAA equalization is a form of pre-emphasis on recording and de-emphasis on playback. The obvious consequence was that different reproduction results were obtained if the recording and playback filtering were not matched. īefore then, especially from 1940, each record company applied its own equalization over 100 combinations of turnover and rolloff frequencies were in use, the main ones being Columbia-78, Decca-U.S., European (various), Victor-78 (various), Associated, BBC, NAB, Orthacoustic, World, Columbia LP, FFRR-78 and microgroove, and AES. The RIAA equalization curve was intended to operate as a de facto global industry standard for records since 1954, but when the change actually took place is difficult to determine. The purposes of the equalization are to permit greater recording times (by decreasing the mean width of each groove), to improve sound quality, and to reduce the groove damage that would otherwise arise during playback. RIAA equalization is a specification for the recording and playback of phonograph records, established by the Recording Industry Association of America (RIAA). ![]() ![]() The recording curve performs the inverse function, reducing low frequencies and boosting high frequencies. The RIAA equalization curve for playback of vinyl records.
0 Comments
Leave a Reply. |