transformer at input pickup sim & pulldown

[m_charles]

Hi. Just gotta say, that transformer at input to simulate a pickup, when after a buffer works flawlessly (orman, escabado). An answer to my prayers, I love it. Hate having to worry about chain placement with my FF.

2 questions.

1) Would a pulldown go before or after the tranformer? My logic is that a pickup wouldn't see a pulldown until AFTER itself. So should the pulldown for pop prevention go after the trans? or does it even matter...?

2) Was surprised to find that the transformer didn't affect the sound when a guitar actually was plugged in directly to the FF. Why is this??

thanks! Chuck

[petemoore]

  Xfomers don't do DC. Only AC that goes in comes out, I hope.
  I've read something of DC Xformer but it's at least quite rare, not what we're doing.
  They don't store DC charge like capacitors do.
  This is what causes pops and requires the capacitor pulldown resistor to drain the capacitor voltage to Gnd.

[earthtonesaudio]

You might not need a pull-down at all.

While the purpose of the pull-down is to drain charge that accumulates on the input coupling cap, the "pop" you hear is due to all that charge quickly being switched to a different DC potential.  Having an inductor in between the cap and the switch slows that switching, so the cap may lose/gain charge more slowly.  This may be enough to make the pop inaudible.


If you still hear a pop, I'd recommend placing the resistor before the inductor (on the 'input' side of the inductor, not the 'cap' side).

[m_charles]

thanks guys. Just FYI, ended up putting in a 2.2M after the trans. Seemed to not make any difference either way. I agree earthtones, probably not necessary, but I didn't feel like cutting it so I just left it.