375-0-375 for a KT66 build?

[soma_hero]

So the Hammond 158L is only rated for 400V. I'm guessing I'll have around 450V or so. Any recommendations on another choke?

Also, how can I figure out what values to use in the resistor dropping string? I would need to know the current being pulled right? Going off of the voltages posted by Ron, there is 0.5mA from B+4 to B+5, 2.75mA from B+3 to B+4, 3.75mA from B+2 to B+3, and 27mA across the choke.

So now I need to estimate what voltage I'll have coming off the secondaries, and using these current pulls and the expected voltages posted I can calculate the resistor needed to drop the voltages. Ideally I would only need to adjust the choke (since I'll need one rated higher voltage) and the first dropping resistor(2x9.1K) right? All else should fall into line?

Thanks for all the help!

[Blind Lemon]

I am in the process of finishing off a Rocket w/El84s and played it threw a 2/10 w/Warehouse speakers this last weekend. I ordered a set of them Monday. Nice and tight with a lot of punch. Good bass but really scream when cranked. Use them in pairs or more they are only rated for 20 watts.

BL

[Markusv]

[quote="soma_hero"]So the Hammond 158L is only rated for 400V. I'm guessing I'll have around 450V or so. Any recommendations on another choke?

quote]

Have you looked into the specs of the original AC 30 choke?
Still, voltage wise, Im not sure it'll exceed 400v

Markus V

[soma_hero]

Looking at the GZ34 datasheet, it says if Vin is 350V, Vout is 380V.

Using diodes the Output to input ratio is Sqrt(2) - Vdiode right? So the tube isn't supposed to multiply the voltage as much, and should drop more than the diodes drop.

However, in PSU Designer II I modeled this power supply and found that using the GZ34, the output DC is still at 453V. This is Vin * 1.414 - ~50V. Which is correct?

Need to know if the voltage will start at above 400V for B+1 and B+2, since I have a choke rated for 400V here....

Attached is my PSUDII file. I modeled using the choke i have here (9h, 40mA, 300ohm) and adjusted the dropping string for good preamp values.

[Zippy]

...and adjusted the dropping string for good preamp values.

What are you calling "good" preamp values? Typical voltages for the Rocket or what?

[soma_hero]

Yeah, close to what Ron posted for typical values.

[Zippy]

Good stuff, Soma'. I have a theory that one can play with the output section as much as they like, as long as the preamp voltages are maintained, and still keep much (most) of the character of the design.

[M Fowler]

Soma-hero,

How can I extract that RAR file without buying more software?

Mark

[Rimy]

mark

go and find 7-zip.
it's freeware.

ralph

[soma_hero]

Here it is in .zip format.