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Need help putting together small Phono Preamp for Xmas

Proschuno

Aug 1, 2011
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Aug 1, 2011
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So basically I bought my sister a record player, without realizing that the signal they make is far too small to be heard on computer speakers… I successfully built one using a 12ax7 tube, but I'm just now getting my feet wet with semiconductors… backwards, right? These are the opamps I have:

http://www.fairchildsemi.com/ds/KA/KA324.pdf

http://pdf1.alldatasheet.com/datasheet-pdf/view/908/MITSUBISHI/M5218.html

http://pdf1.alldatasheet.com/datasheet-pdf/view/25085/STMICROELECTRONICS/TDA7266.html

and a 741 Opamp…

Would any of these opamps be suitable for making a phono-preamp? I've been trying with the m5218 and 741 with no luck, but I'm sure it's just my breadboard skills (or lack thereof….)
 

Proschuno

Aug 1, 2011
94
Joined
Aug 1, 2011
Messages
94
and I'm wanting to use semiconductors because I have a ton of them and would like to put them to use without making a run to Radioshack…. and I don't feel like putting dangerously high voltages near my sister's turntable nor computer speakers.
 

Arouse1973

Adam
Dec 18, 2013
5,178
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Dec 18, 2013
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5,178
Oooh your looking at a quite complex circuit here to design yourself if you want true RIAA response. When they made records they used to reduce the low frequency signals and boost the high signal to prolong the life of the stylus and help with pops from the record itself. You need to do the reverse that they didn't when they made the record otherwise it won't sound very good. Look for a Lipschitz network amplifier, this might help.
Adam
 
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