Tom, My very first project with tubes was an Aikido cathode follower preamp, using 6DJ8's that you were kind enough to gift me in that care package you sent about 9 years ago. It has been in my system continuously for that long because it sounds so good. I direct copied the main circuit topology from TubeCad's website then scratch designed my own tube rectified power supply. That's why I was asking if you had anymore NOS 6DJ8's
Ahhh - either I didn't know or had forgotten you had built that design. My memory sure isn't my strongest asset these days! I'm guessing the Aikido is a better linestage than my little SRPP 6BH7. I might have to build one for myself now.
9 years ago? Has it been that long? Man, time flies! I do have a bunch of those 6DJ8s - not NOS, but they tested fine. Do you need a quad?
Good to hear. Look forward to seeing more of your excellent point to point wiring technique. Now that you are back into tubes, you will have give your industrial TV-7 the "self-calibration" treatment. Which reminds me, I still have to "self-calibrate" my Heath-Kit TT1. Then I can start running up matched pairs of power output tubes taking actual transconductance (gm) measurements, and comparing them to the published figures in the RCA receiving tube manuals.
I've decided to add a small 12.6 volt filament transformer to this project so that I can use 12SN7 and 12SX7 tubes instead of the 6 volt 6SN7 tubes. Cost wise the 12 volt filament tubes are a fraction of the cost for NOS tubes. Like $6 per tube vs $50 to the moon!
Craig - Do you just need a pair of 6SN7's? $50 is ridiculous! There are tons of NOS 6SN7s around. Somebody is seriously hyping these things up just to raise prices. I can sure send you a few of those. Heck, I have a small stack of NOS on the shelf right next me. If you want 12SN7s, I'm pretty sure I have a few of those, but they might not be cosmetic matches.
I think you need a tube care package - xSN7s & 6DJ8s! I'll see if I still have your address.
I started reading that CCDA article. Interesting stuff - I might be able to convert my little VTV 6SN7 linestage to that topology. I'll have to see if I can get a B+ of 200v with the PT on that chassis. I never loved the VTV circuit - at least not my build of it.
Comments
My very first project with tubes was an Aikido cathode follower preamp, using 6DJ8's that you were kind enough to gift me in that care package you sent about 9 years ago. It has been in my system continuously for that long because it sounds so good. I direct copied the main circuit topology from TubeCad's website then scratch designed my own tube rectified power supply. That's why I was asking if you had anymore NOS 6DJ8's
9 years ago? Has it been that long? Man, time flies! I do have a bunch of those 6DJ8s - not NOS, but they tested fine. Do you need a quad?
I think you need a tube care package - xSN7s & 6DJ8s! I'll see if I still have your address.
I started reading that CCDA article. Interesting stuff - I might be able to convert my little VTV 6SN7 linestage to that topology. I'll have to see if I can get a B+ of 200v with the PT on that chassis. I never loved the VTV circuit - at least not my build of it.
any details on these or opinions?