Transformer balancing the output of a Blue Clipper? Output Z question...

[therecordingart]

http://www.beavisaudio.com/schematics/Images/Dan-Armstrong-Blue-Clipper-Schematic.png

I'm being an idiot and could use some help. I want to put a balanced out on a Blue Clipper, but am having a brain fart and can't figure out the output impedance. Is it as simple as adding up the series resistance? (18.2k when the volume is dimed?) I have an Edcor 10k/600 transformer that I'm thinking might work, but need help from someone smarter than me.

[PRR]

You fergot the 50K.

Looks like 13.3K when not clipping, near 8K when clipping, and much lower for anything over 400Hz due to the large capacitor.

10K:600 is not wrong; you are taking more than 4:1 loss (4:1 in transformer, plus loading loss) so output is more mike-level than line-level.

It really just uses one half of a two-opamp chip? Then rig the other half as unity-gain buffer, add 100 ohms series on the output, and use that to whack the transformer better. You can probably run 600:600 and get a fine line level. Or 10K:600 and pot-down a bit for a mike-level. Either way the low-low source impedance swamps much of the transformer's faults, and sucks-up more crap picked-up on long lines.

Are R1 and R2 supposed to be very different values? And R1 so small? Seems like R1 could be 10X bigger.

[therecordingart]

Are R1 and R2 supposed to be very different values? And R1 so small? Seems like R1 could be 10X bigger.

I've built a bunch of variations of this, and I like to bias it at half supply (R1 and R2 are 1M). So is the output Z the sum of the pot, R5, and R6? So put a buffer on the end of this -> series 100R resistor -> 600:600 xfmr?

Here is a crude Windows Paint drawing:

http://i.imgur.com/xWwMFiZ.png

I appreciate the help!

[duck_arse]

some biasing info here:

http://runoffgroove.com/newclipper.html

[PRR]

> is the output Z the sum of the pot, R5, and R6?

Pot is parallel to the others.

It's too cold here to teach basic series/parallel resistance networks. There are books with more patience than me. Boylestead may be one; many others.

> put a buffer on the end

AND some DC biasing/coupling to account for your single supply.

http://i.imgur.com/T670gSH.gif