Yeah, saw that with the 1650TA, but I can't get one of those, Tube-town has only got the 1650T, and the other shops don't haven't even got hammond transformers (TAD, musikding, reichelt, conrad...).
![angry :x](https://forum.sunnstillshines.online/Smileys/default/angry.gif)
However, two new things have come up:
The power transformer seems a bit oversized upon closer examination.
800V RMS with C.T. is a bit too much, is't it? that would be like 1kVDC after rectification and a filtercap.
I therefore chose the 372LX, 600VAC RMS should be enough.
And then I discovered that the 372LX has got a 5V winding for tube rectifiers...
That's it, I'm sold.
Looking at a Sunn 2000S schematic (
http://www.4tubes.com/SCHEMATICS/BY-BRAND/Sunn/2000s.gif), I could just run two GZ34's in parallel and get my 550VDC this way. (Do I even need that much? The 1. gen schematic isn't that clear, after two caps and a Choke it should be ~500VDC)
But then I need a smaller transformer, as the GZ34 is only rated for max. 550VAC (Plate to Plate).
The 370LX comes to mind...
So I'm basically stuck with the decision of my PT. What do I need, what considerations are there to make with tube rectification? The GZ34 Datasheet recommends ~200Ohm limiting resistors, but the sunn 2000S hasn't got them -> Are they really neccesary?.
AND EVEN if I go with diodes, the question remains: How much RMS do I need on the sec. HV winding?
This Project is getting more and more complex
![Wink ;)](https://forum.sunnstillshines.online/Smileys/default/wink.gif)
cheers
PS: I've just finished building the preamp, I made myself a 300VDC supply with two 230V/12V transformers and use the master volume output (In the 1. gen schematic) to feed the FX-return of a Transistor-Amp (H&K Tour Reverb). SOUNDS F'IN AWESOME!!
![Smiley :)](https://forum.sunnstillshines.online/Smileys/default/smiley.gif)
Maybe I'll post some photos soon...