I want to thank you again Vicenajay. I'm still loven' the TNC ACMP-73 it's a great unit!!!
Moresound - AWESOME! These are really great preamps, but what I like the most is the analog EQ circuit....so tweakable without any phase wonkiness.
Yeah, I have 4 of them.
2 dedicated to drum kit , one to vocal and 1 to bass guitar.
I wished I had picked up a few more.
I know this thread is years old. You seem very knowledgeable about the TNC ACMP units. I recently purchased one. Did anyone ever figure out any proper solutions to fix the pop on the input gain? Also, have you played around with any modifications for these units? I have the 84.The TnC ACMP preamps. The 73, 84 and 81's all have the same gain switching arrangement, which transiently connects the output of the first preamp stage to its input at switch position 7, causing it to oscillate, producing a huge voltage spike which is amplified and can cause the output transistor's emitter resistor to fry, and damage equipment connected downstream.
There are several corrections for this, but they either cause loss of one gain position, or are electromechanically difficult to implement. Make sure the unit you are buying has had this corrected, or that you are willing/able to do it yourself. The easiest fix is described here:
https://homerecording.com/bbs/showpost.php?p=3090921&postcount=12
I was trying to visit the link that details the easiest fix you posted...the link isn't active. Or at least it seems that way.To my knowledge there is no "proper fix" commercially available currently, though it is possibly being worked on.
Easiest by far is moving one end of a resistor. This can be done without removing the board from the unit. You lose one gain position, but this is of minimal importance.
Nice! Thank you!@iamdeshawnwhite - This link will take you to the post crazydoc linked to.