Classic Neumann OA10 discrete op-amp converted to more usefull API2520 (and many others) format. This is something that I designed a few years ago and I even built a prototype but never had time to do the listening tests...
Documents:
Schematic
http://audioxxx.googlepages.com/OA10_schematic.pdf
Component layout with designations
http://audioxxx.googlepages.com/OA10_layout_designations.pdf
Component layout with values
http://audioxxx.googlepages.com/OA10_layout_values.pdf
Pinout and dimensions
http://audioxxx.googlepages.com/OA10_pinout_and_dimensions.pdf
Compensation
http://audioxxx.googlepages.com/OA10_compensation.pdf
Top copper layer pdf for home etchers
http://docs.google.com/fileview?id=0B_XBYPfmG8pVYmQxYjAyMTctMTViZC00MjMzLWIzMjYtZTg0Y2E2ZTczYjMz&hl=en
Bottom copper layer pdf for home etchers
http://docs.google.com/fileview?id=0B_XBYPfmG8pVNTBhYzFjM2YtNTlhMi00MmY0LTlkMTMtNGNmZTE0NjQ1ZThh&hl=en
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My other projects:
Studer 169 EQ
http://www.groupdiy.com/index.php?topic=33996.0
Neumann W492 EQ
http://www.groupdiy.com/index.php?topic=28332.0
Balanced 12 input summing amplifier
http://www.groupdiy.com/index.php?topic=29082.0
Balancing/unbalancing amplifier
http://www.groupdiy.com/index.php?topic=29333.0