Go Between with Tube Mixers - MX10, 1567a
Posted: Fri Jan 20, 2012 1:47 am
Hi so I made a 4 channel Go Between front end for using condensers with some older preamps. All four seem to work great when plugged into my Ampex 351, but I can't get a good signal when using condensers going into my Ampex MX10 and I had a similar issue with an Altec 1567a.
They do everything they're supposed to if I run a dynamic through them into the mixers, but when I plug in a condenser (AT4033 or Earthworks TC25) I get a very weak distorted signal when the 48V is engaged. The level actually seems to go up a little bit when I engage the pad. And the weirdest thing is that when I disengage the pad there are a few seconds where it actually sounds good, loud and clear and then fades away back to the quiet distorted signal.
As a side question, is the phase switch before or after the 48V? Might there be a pin 2 hot vs 3 issue that the could be resolved if I rewired the cables going to the mixer inputs? I kind of figured the phase would fix that. And to be perfectly honest, I think I was only getting signal when the phase was engaged, but can't quite remember as I'm away from the gear right now.
I'm guessing it's impedance related, but just don't know enough to say.
Any help on this would be appreciated. Thanks!
They do everything they're supposed to if I run a dynamic through them into the mixers, but when I plug in a condenser (AT4033 or Earthworks TC25) I get a very weak distorted signal when the 48V is engaged. The level actually seems to go up a little bit when I engage the pad. And the weirdest thing is that when I disengage the pad there are a few seconds where it actually sounds good, loud and clear and then fades away back to the quiet distorted signal.
As a side question, is the phase switch before or after the 48V? Might there be a pin 2 hot vs 3 issue that the could be resolved if I rewired the cables going to the mixer inputs? I kind of figured the phase would fix that. And to be perfectly honest, I think I was only getting signal when the phase was engaged, but can't quite remember as I'm away from the gear right now.
I'm guessing it's impedance related, but just don't know enough to say.
Any help on this would be appreciated. Thanks!