Here's some pics of a tube preamp I recently finished. Two channels, fixed gain is adjustable from 60 to 72db, 3 triode stages with interstage volume control and input pads that go from mic to line range. Design could be loosely considered as an RCA BA-2 with an extra gain stage. Plate loading on low level stages is a bit lower than BA2, output stage is exact same with same OTs. Iron compliments of emrr. Sounds great and represents the best I could think of for a SE direct coupled output tube mic amp in terms of gain, flexibility, and fidelity. Took the better part of a month to complete including bench test time and research.
front:
http://i409.photobucket.com/albums/pp179/lassoharp/DYI%20preamp%20%20Nov%202011/frontweb.jpg
3/4 side R:
http://i409.photobucket.com/albums/pp179/lassoharp/DYI%20preamp%20%20Nov%202011/P1030039.jpg
3/4 side L:
http://i409.photobucket.com/albums/pp179/lassoharp/DYI%20preamp%20%20Nov%202011/P1030038.jpg
gut:
http://i409.photobucket.com/albums/pp179/lassoharp/DYI%20preamp%20%20Nov%202011/P1030045.jpg
rear:
http://i409.photobucket.com/albums/pp179/lassoharp/DYI%20preamp%20%20Nov%202011/DIYpreampFBrearBW.jpg
front:
http://i409.photobucket.com/albums/pp179/lassoharp/DYI%20preamp%20%20Nov%202011/frontweb.jpg
3/4 side R:
http://i409.photobucket.com/albums/pp179/lassoharp/DYI%20preamp%20%20Nov%202011/P1030039.jpg
3/4 side L:
http://i409.photobucket.com/albums/pp179/lassoharp/DYI%20preamp%20%20Nov%202011/P1030038.jpg
gut:
http://i409.photobucket.com/albums/pp179/lassoharp/DYI%20preamp%20%20Nov%202011/P1030045.jpg
rear:
http://i409.photobucket.com/albums/pp179/lassoharp/DYI%20preamp%20%20Nov%202011/DIYpreampFBrearBW.jpg