Would this work (simple OPA1632 phono preamp)?

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My quest is for a simple inexpensive balanced phono preamp. Not too many examples out there. So I drew up my own. It is basically just Rod Elliott's RIAA opamp eq from Project 25 http://sound.westhost.com/project25.htm thrown into the feedback loops of an OPA1632, as shown.

My questions are pretty basic: Would it even work? What enhancements would you make?
 

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HBarske said:
As the OPA1632 behaves more like an inverting topology, you might better have a look at RJM's "VSPS Ultra": http://www.geocities.com/rjm003.geo/rjmaudio/diy_pho7.html

Actually, the VSPS is closer to what I need. The VSPS Ultra omits the input resistor to get extra gain for an MC cartridge. I am building for an MM cartridge and need that input resistor. I was not going to mistakenly short the input resistor to ground if that's what you mean :)
 
Wow, didn't know anybody was still reading this.

carawu said:
Take a look at A. Wrights RTP Riaa.

True, doing that type of passive eq would avoid matching problems, but I have read good things about doing active eq in the feedback loop so I would like to try it.

This is what my current thinking is. The addition of iron to convert to unbalanced may look silly at first, but that is because I am going to use cheap Edcor 10k:10k transformers I have on hand for the unbalanced output, which will likely be a rarely used connection, and I expect the OPA1632 to do a better job.
 

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