Abstract: A quad, low-noise, op amp and LDO are used to build a stereo preamp with RIAA equalization to allow converting signals from a record player (phonograph) to a linear output for digitizing by computer sound cards etc. Maxim > App Notes > AMPLIFIER AND COMPARATOR CIRCUITS AUTOMOTIVE Keywords: low noise, op amp, phono, phonograph, RIAA, preamp, opamp, operational amplifiers, op amps, Mar 14, 2003 amplifier APPLICATION NOTE 1931 USB-Powered High Precision Hi-Fi Phono Preamp Abstract: A quad, low-noise, op amp and LDO are used to build a stereo preamp with RIAA equalization to allow converting signals from a record player (phonograph) to a linear output for digitizing by computer sound cards etc. A phono preamp is needed for preamplifying and equalizing the analog output of the good old record player. The former hi-fi amplifiers or stereos included a phono input, but at this time it is not very common because the CD player has a linear output and doesn't need linearization. If you still want t……