OT - Gain for phono preamp?

[zpyder]

This is a little OT, but a simple question.  I've got a record player and I'd like to build a small preamp for it so that I can plug it directly into a receiver.  I'm guessing nothing special is required here, just an amp, and my only question is, how much gain should I apply to get the phono levels up to regular line levels?

thanks!
zpyder

[Mark Hammer]

A couple of hundred.

Remember that the gain is not applied consistently across the spectrum.  For proper tone, you need to use RIAAA compensation.  Vinyl is recorded with the bass attenuated in a systematic manner so as to be able to squeeze more onto a disc side with narrower squiggles.  On playback, the bass gets boosted but not in as simple a manner as an EQ control would accomplish.

Do yourself a favour and use one of the udoubtedly many 100's of phono preamp schematics out there.  Lord only knows how many were published in ETI, Elektor, PE, and RE over the years to mention but a few.

[Elektrojänis]

Check out these:

http://sound.westhost.com/project06.htm
http://sound.westhost.com/project25.htm

I hve not tried these myself, but based on the articles on that site, Rod Elliott seems to know his stuff.

[grapefruit]

If you have "The Art of Electronics" there's one in there that only uses one op amp per channel IIRC. One LM833 or NE5532 would do the job for a stereo unit.

Cheers,
Stew.