The Firebomb doc is complete and can be downloaded here:
http://www.madbeanpedals.com/projects/Firebomb/docs/Firebomb.pdf
Excellent work!
I noticed the 1M resistors (R1 and R10) are gone from the channel A and B inputs... just curious and trying to learn how things work. :)
Those were never really part of the stock design. I originally added them because I know some people insist on pulldown resistors, so I left that option. But, there's a really good reason not to have them: it changes the input impedance. Actually, it lowers it in this case. Since all the SHO type builds I've done do not have popping when the pulldown is excluded, I decided to leave them off the design for good.
Quote from: madbean on May 11, 2011, 07:11:30 PM
But, there's a really good reason not to have them: it changes the input impedance. Actually, it lowers it in this case. Since all the SHO type builds I've done do not have popping when the pulldown is excluded, I decided to leave them off the design for good.
Thanks for such a prompt response... I imagine you are really busy.
I will build the Firebomb in the near future (v.3), so should I install the resistors for that design, or would adding jumpers be better? I ordered plenty of 1M resistors, so logistics/supply is not a problem.
FYI, as soon as I work out the design of my testing rig (I am following Jacob's designs), I'd like to talk to you about doing (very simple PCB) custom work for the rig. Before I start building my Madbean pedals, I want to test everything using a bread board in order to learn the craft better... and recover from mistakes and minor explosions more quickly and cleanly. ;D
You definitely don't want to add jumpers as that would ground the input signal. If building ver.3, I suggest putting sockets in there and try with and without the 1M pulldown to see if it makes a difference for you.
Sure, feel free to email me about your testing rig idea.