RIAA Compensated Stereo Preamp  
  If your stereo amplifier does not have an input for a record player, you should use this circuit between your turntable and your amplifier. The output of your turntable follows a gain-bandwidth curve called the RIAA compensation curve. The standard AUX input on your stereo does not. Records will sound very strange without an RIAA preamp.
 
Stereo RIAA Preamp
 
The RIAA compensation curve was adopted in the mid 1950s, as a way of dramatically improving the fidelity of playback. This curve takes into account the limitations of the mechanican recording system on the record surface. At low frequencies, this amplifier provides 20dB of gain. At medium frequencies it provides no gain, and at high frequencies it provides 20dB of attenuation.
 
 
  Note that only two Opamp packages are used. Each type is actually a dual Opamp. The left and right amps share one amp of each type from each dual package. This circuit is also used as the example for the "Custom Etched Circuit Boards" section. In that section you will find instructions for making a custom circuit board for this preamp. If you want to make your own circuit board for this project, you can download full size artwork there as well.
 
 

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