Here are a couple simple preamps I drew for protoyping. It is built on the protoboard you can get from futurlec.
These two designed work great for me.
The power supply is not shown, but any decent power supply from +/-10V to +/-18V should work fine.
I build mine with a regulated +/- 12V supply.
Only one channel is shown. You can build two channels per side of the board, which if you are doing a stereo preamp allows you to use the entire other side for the power supply which is what I did.
I can send a drawing of the PS and photos if you wish.
Drawing #1 is the opa627/637 + buf634 version.
Drawing #2 is a LT1015 + LT1010 version with 2 channels shown. This version may benefit from a 5-100pf cap soldered direct between the negative input and the output of the LT1015 if you see any instability. The biasing for the LT1010 will make it run pretty hot. You can safely omit the biasing resistor, or use a high value like 1K.
Both also make excellent headphone amps.
Humbly submitted in the hope you have some fun.
[IMGDEAD]http://www.sequenet.com/images/preamp1_a.jpg[/IMGDEAD]
[IMGDEAD]http://www.sequenet.com/images/preamp2_a.jpg[/IMGDEAD]
These two designed work great for me.
The power supply is not shown, but any decent power supply from +/-10V to +/-18V should work fine.
I build mine with a regulated +/- 12V supply.
Only one channel is shown. You can build two channels per side of the board, which if you are doing a stereo preamp allows you to use the entire other side for the power supply which is what I did.
I can send a drawing of the PS and photos if you wish.
Drawing #1 is the opa627/637 + buf634 version.
Drawing #2 is a LT1015 + LT1010 version with 2 channels shown. This version may benefit from a 5-100pf cap soldered direct between the negative input and the output of the LT1015 if you see any instability. The biasing for the LT1010 will make it run pretty hot. You can safely omit the biasing resistor, or use a high value like 1K.
Both also make excellent headphone amps.
Humbly submitted in the hope you have some fun.
[IMGDEAD]http://www.sequenet.com/images/preamp1_a.jpg[/IMGDEAD]
[IMGDEAD]http://www.sequenet.com/images/preamp2_a.jpg[/IMGDEAD]