Hi,
I just finished building Der Buffer. I ordered the PCB and then soldered all the components. I chose to build the Germanium type (using an AC128 transistor).
The weird this is, when the pedal is engaged I get a slight drop in volume and dynamic and quite a drop in high frequencies - which is exactly the opposite of what a buffer should do 
I double checked all the components, and they are right values and right position. The only doubts I have are:
- I used a couple of 2W metal film resistors instead of the 0,6W metal film I usually use
- C2 is a MKS WIMA 1mF capacitor, while I use an MKT 0,1mF for C1
Could those things completely change a circuit behaviour? Or should I look into something else.
Also, I notice a pop when I engage/disengage the pedal, so I suppose the is some DC leaking. Where can I solder a pull-down resistor to eliminate this? I assume from negative lead of C4 capacitor to ground, is that right?
Thank you in advance