Re: Simple Op Amp RIAA preamp 1st lash up
If you are putting an electrolytic from R2 to ground to make an LF roll-off that is the wrong way to go. The tolerance on electrolytics is very wide, and they can introduce harmonic distortion.
Bung another stage on and build a Sallen and Key second or third order filter around it using film capacitors.
Anyhow, the RIAA values in the phoneclone are absolulely fine. Time constants all work out very close to correct.
Craig
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