At the BAF2013 Mr. Pass presented a nice JFET preamp. Today I cobbled up a quick prototype of one channel to test its behaviour and it's very nice. I have a BL rated Toshiba JFETs so some values had to be changed and some parts added (P1 to set the DC offset at the output and harmonic content, caps in cascode voltage divider to improve HF extension a bit). Serious build with buffer added at the output will follow. For the time being here is the schematic and the PCB layout of the preamp (copper side view, 45x50mm) :
EDIT (Oct. 27, 2013): 'final' schematics and pic of built preamp are in the post #66
EDIT (Oct. 27, 2013): 'final' schematics and pic of built preamp are in the post #66
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