RIAA playback equalization is not a simple low-pass filter. Players must, therefore, be designed to limit rumble, more so than if RIAA equalization did not occur. This also reduces physical stresses on the stylus, which might otherwise cause distortion or groove damage during playback.Ī potential drawback of the system is that rumble from the playback turntable's drive mechanism is amplified by the low-frequency boost that occurs on playback. Groove width is thus reduced, allowing more grooves to fit into a given surface area, permitting longer recording times. 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 current value of the slider can be seen by hovering over it with the mouse.The RIAA equalization curve for playback of vinyl records. This can make setting the value you want easier. The sliders can also be made taller by resizing the dialog. Holding down Shift then either dragging the slider handle or using the arrow keys to increment by 0.1 dB.Using the arrow keys on the keyboard to increment by 1 dB.Clicking above or below the slider to jump to a nearby whole dB value.Clicking above or below the slider to increment it up or down by a fixed value in whole dB.You can get to an exact slider value but the method depends to some extent on your operating system. Click and drag the slider up or down to increase or decrease the volume by a maximum of 20 dB. Each slider adjusts the gain of a specific range of frequencies, the gain being maximized at (centered on) the frequency stated on the slider. Frequency Sliders: the equalization curve is drawn by manipulating a set of sliders.
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