I just got a handful of old TI 2n1306's and decided that I better use some of these so my friends don't start calling me a hoarder. I've gotten many of these in the past and they always seem to be a safe bet in untouched batches. My yield usually falls in the 80-90% range. The gains were all between 70 and 140. I decided to do a Jon inspired 1590a build this time around I made a very compact Vero layout that would just fit into the enclosure. I made the attack knob a trimmer. I find that with this circuit I usually leave the attack about halfway up and control the gain with the guitars volume knob; with this pedal there is a small hole in the back plate to adjust to the position I like. To my ears the NPN's tend to have better bottom end than the PNP's and I thought it would be interesting in this circuit considering how little bottom end it usually has. The gains are Q1=70; Q2=75; Q3=110. I keep all my 1590a builds super simple looking and they are looking good when I put them all together on one board.
(http://i693.photobucket.com/albums/vv299/pnordeen/20121111_152418.jpg)
(http://i693.photobucket.com/albums/vv299/pnordeen/20121111_152405.jpg)
Nice! So how does it sound? Did you get more bottom?
C
Love it.... thats a neat vero layout too! 8)
Very very cool.
I too am putting together a 1590A pedalboard. Just haven't started on the board part of it yet.
Thanks Guys!
It does sound like the bottom end is a little more pronounced Cliff. I think it also helps that I swapped the output cap to 56nF but it still has more bass presence than my other OC75 MKII with a 68nF output cap. This one has incredible sustain too. Maybe a video demo if my roommate ever leaves the damn apartment >:(
Ha! Those pesky roomates.
I like the 2n1306s you used here. Those are the ones I found in our electronics lab where I work--I was pretty excited since the 2n1304 you sent me for my Cosmo sounded so good. I used one on my "Fuzzball" (Keeley Fuzzhead-based) board (see Ian's layout in Member Projects). It seems these things are pretty consistent. I picked one based on a very un-scientific DMM test, and didn't even think about leakage. Sounded good right away! I'm guessing it's low-ish gain but it's giving me a usable germanium drive sound. Once I get some vero and build a transistor testing board, I'll test the one I used and the 4 or five left down there.
Nice! 1306s are one of my favorite germs.