Univox U1000 -> 6L6 DR103, The HiVox!

[turbofeedus]

Imgur album
Alright, so I posted about this Univox U1000 I picked up a few months back.
I've got it mostly put together now. This uses a 70's DR103 preamp:
Schematic courtesy of Huss
and a basic 6L6 output section (1K screens).
I'm also planning to use the "Channel Select Switch" mod from Sluckey, just waiting on the switch:
Sluckey AC15 mod doc

A couple questions came up;
1) This PT had separate 6V AC windings for the pilot light/preamp tubes, and power tubes respectively. I did artificial center taps for each of the windings, both 10K resistors to ground as usual. Is there any reason this will cause issues?
2) I've placed one set of those 10K artificial center tap resistors off the heater pins on one of the power tube sockets. Is this a bad place for them?
2) The NFB resistor in the hiwatt is 10K, with 450 ohm to ground, but that's going to a 16 ohm tap. I have 4 and 8 ohm taps. If I understand this correctly, then I should do a 5K/470 to the 4 ohm tap for equivalent voltage in the NFB?

Also, if anyone reading this has the internal thought of, "I wonder how they dealt with _____", please, I probably didn't. Ask away.

[sluckey]

I did artificial center taps for each of the windings, both 10K resistors to ground as usual. Is there any reason this will cause issues?

I've never seen 10K resistors used. 100Ω is the most common value. Mounting them on the 6L6 socket is fine.

[Stevem]

A artificial center tap is made from 100 ohm resistors , not 10k resistors.

In terms of the needed feed back resistor each tap lower then a 16 ohm tap will have 33% less voltage out of it then the last so you can scale your resistor needs by that.

Nothing is truly cut in stone with these resistor values and what tap they go on .
Once you get the amp up and running play around with there value to once you find a average volume you will play the amp at mess with the value to find where best it is to have the outout roll over into clipping, that is of course if you play the amp loud enough to use up its RMS wattage!

[turbofeedus]

I did artificial center taps for each of the windings, both 10K resistors to ground as usual. Is there any reason this will cause issues?

I've never seen 10K resistors used. 100Ω is the most common value. Mounting them on the 6L6 socket is fine.

Whoops, brainfart.

A artificial center tap is made from 100 ohm resistors , not 10k resistors.

In terms of the needed feed back resistor each tap lower then a 16 ohm tap will have 33% less voltage out of it then the last so you can scale your resistor needs by that.

Nothing is truly cut in stone with these resistor values and what tap they go on .
Once you get the amp up and running play around with there value to once you find a average volume you will play the amp at mess with the value to find where best it is to have the outout roll over into clipping, that is of course if you play the amp loud enough to use up its RMS wattage!

Alright so maybe I'll start with a 8.2K and see what happens, thanks.

[Stevem]

Also note that the less feedback voltage you apply back in the circuit the less tight the Bass responce will be, but in general let your ears be your guide!