GeoFex style ABY box with mods - Schematic Question

[brazdj]

Hello,

I have been reviewing different schematics for ABY boxes and came across this thread https://www.diystompboxes.com/smfforum/index.php?topic=96178.0. I decided to start a new thread since I will be asking slightly different questions.

Basically I would like to create RG's Hum-Free(er) box with the option for buffer/no buffer on the outputs as well as a selectable phase inverter on output B. I combined a few schematics from around the web and came up with the below.




If anyone would be so kind to take a look at the schematic and point out any errors, I would be very appreciative. I am mostly curious about the phase inverter, which is currently a dpdt on the transformer secondary that simply swaps wires around. Is this switch appropriately located or should it be placed on the primary side of the transformer?

Thank you in advance,
Daniel

[garcho]

where is it going to be in your signal chain?

[bartimaeus]

I may be wrong, but it seems like the 220nf cap and 1m resistor in front of each buffer will form a highpass filter at a super high frequency, which would effectively silence your audio signal?

Overall the general layout seems good though! Some folks also include an input buffer but it seems like that often isn't necessary. Unfortunately I can't say whether your polarity switch is correct.

[njkmonty]

Unfortunately I can't say whether your polarity switch is correct.

from memory im pretty sure the phase switch diagram is exactly the way i did it

[PRR]

> seems like the 220nf cap and 1m resistor in front of each buffer will form a highpass filter at a super high frequency

One milli Ohm would be wrong.

I would assume one MEG Ohm, which is below 1Hz, so plenty good. (0.01uFd 10nFd might be fine, but it is good to be generous, so >0.1uFd 100nFd.)