T
tubejay
Guest
So I replaced the input coupling caps on my PM1000 from a polarized tantalum cap, to a non-polarized film, and I think I'm having some problems due to this. Is it possible that because it isn't polarized that I'm sending voltage BACK to whatever is plugged into it?
If I use mics with the two modules that I made this change on, it works fine, and sound really nice, registering no level of any frequency on my VU's or in Pro Tools. However, if take the mix buss outs of my TAC Scorpion and plug it into the inputs (mic and line go in the same input and there is no mic line switch, only a stepped gain switch) then the Scorpion freaks out a little bit. The meters on the master buss go nuts and slam. There's no audible sound of any noise happening to warrant the meters slamming up like this, and when I play music through the Scorpion it still sounds the same, and when I listen off the headphone amp of the PM1000, it also sounds fine. Could this be an oscillation? It only does it when the OUTPUT of the tac scorpion isplugged into these modules with the changed film caps. I actually replaced ALL of the tantalums (3 of them, I didn't recap the echo sends) with film caps.
Seeing as I recapped two modules and they are both behaving the same way, and the ONLY difference between these two modules and the rest that I recapped is the film caps and direct outs (which is a transformer wired off of C37) which was not plugged into anything during the test, and the other modules, it has to be these film caps.
Any thoughts? Here's the schematic:
http://home.new.rr.com/lordjimbo/PM1000E_2.pdf
Thank you!
Jay Lison
If I use mics with the two modules that I made this change on, it works fine, and sound really nice, registering no level of any frequency on my VU's or in Pro Tools. However, if take the mix buss outs of my TAC Scorpion and plug it into the inputs (mic and line go in the same input and there is no mic line switch, only a stepped gain switch) then the Scorpion freaks out a little bit. The meters on the master buss go nuts and slam. There's no audible sound of any noise happening to warrant the meters slamming up like this, and when I play music through the Scorpion it still sounds the same, and when I listen off the headphone amp of the PM1000, it also sounds fine. Could this be an oscillation? It only does it when the OUTPUT of the tac scorpion isplugged into these modules with the changed film caps. I actually replaced ALL of the tantalums (3 of them, I didn't recap the echo sends) with film caps.
Seeing as I recapped two modules and they are both behaving the same way, and the ONLY difference between these two modules and the rest that I recapped is the film caps and direct outs (which is a transformer wired off of C37) which was not plugged into anything during the test, and the other modules, it has to be these film caps.
Any thoughts? Here's the schematic:
http://home.new.rr.com/lordjimbo/PM1000E_2.pdf
Thank you!
Jay Lison