Carl_Huff
Well-known member
Hello all,
I have and am stocking two DOAs. I've built projects with these and like them a lot.
DOA #1 - Is the SGA-SOA v2 as designed by our own Samuel Groner on an improved double sided PCB designed by me. I am offering this with Sams full knowledge and support. This is an excellent all BJT design offering a 'full throated' and robust sound that does not cause ear fatigue over loud and long listening sessions.
DOA #2 - Is the classic MOX JFET Op Amp. This one features a matched FET front end pair. I have versions that use (NOS) Toshiba SK389s, LSK389s from Linear Systems and the (NOS) NEC uP686 parts. This DOA affords the intimacy and detail that you can expect from a classic FET design.
I have put up a web page for those that want to further explore or even purchase these DOAs. https://kadproducts.com/
I have both unpopulated PCBs and finished and tested modules. Both are built using the classic PRO 2520 pin sockets and can be swapped into existing legacy gear designed for older DOAs. Both the BJT and FET DOAs are unity gain stable. Both sound great!
Here is a PIC of a pair of Sam's DOAs used in a headphone amplifier. The headphone amplifier is from Sams application notes for his first version DOA. Details for this project can be found on his website. http://www.nanovolt.ch/resources/discrete_opamps/index.html
I also have a phono amp project and a full blown audiophile preamplifier based around these modules. If there is enough interest I could make the details of these designs available.
Have I stirred an interest? Or am I the last old timer that sees value in discrete op amps?
I have and am stocking two DOAs. I've built projects with these and like them a lot.
DOA #1 - Is the SGA-SOA v2 as designed by our own Samuel Groner on an improved double sided PCB designed by me. I am offering this with Sams full knowledge and support. This is an excellent all BJT design offering a 'full throated' and robust sound that does not cause ear fatigue over loud and long listening sessions.
DOA #2 - Is the classic MOX JFET Op Amp. This one features a matched FET front end pair. I have versions that use (NOS) Toshiba SK389s, LSK389s from Linear Systems and the (NOS) NEC uP686 parts. This DOA affords the intimacy and detail that you can expect from a classic FET design.
I have put up a web page for those that want to further explore or even purchase these DOAs. https://kadproducts.com/
I have both unpopulated PCBs and finished and tested modules. Both are built using the classic PRO 2520 pin sockets and can be swapped into existing legacy gear designed for older DOAs. Both the BJT and FET DOAs are unity gain stable. Both sound great!
Here is a PIC of a pair of Sam's DOAs used in a headphone amplifier. The headphone amplifier is from Sams application notes for his first version DOA. Details for this project can be found on his website. http://www.nanovolt.ch/resources/discrete_opamps/index.html
I also have a phono amp project and a full blown audiophile preamplifier based around these modules. If there is enough interest I could make the details of these designs available.
Have I stirred an interest? Or am I the last old timer that sees value in discrete op amps?