414 acting weird

Trying to find a pattern or something but here is the story. Got a newier 414(one with pattern button vs switch) that hit the repair bench a few weeks ago with a rattle. Drummer hit it hard and the rattle was a screw terminal loose/off from the capsule. Reattached the ground terminal for one side of the capsule, the mic tested o.k. on all patterns, and went back into service. Fast forward to now. The mic is in a studio with an api 500 rack, avalon 2022 pre and a neve vr.  The 414 wil work with any pre on console or outboard except  either of the 2 x 512 in the api rack. When patched to the 512 it appears to not get enough phantom power, will not switch patterns and souns weak. Now if i use any other condenser mic with the 512 like a neumann 87, it works just fine as well as works with other pre's in the room. More over if i bypass the studio wiring and go right into back of the 512 in the 500 rack it will work just fine.

According to the AKG specs the 414 eats 4mA off the phantom power.  The Neumann U87AI needs only 0.8mA.
In other word, the Neumann, and many other mics, are much less demanding in regard to the phantom supply, and will work flawlessly in situations where a 414 will be starved.
Since it has been hit, you may want to check the power consumption by measuring the voltage drop across the 6K8 resistors of a known good phantom psu.

Then I'd investigate the studio wiring between the happy and the mic box...

Axel

mad.ax said:

According to the AKG specs the 414 eats 4mA off the phantom power.  The Neumann U87AI needs only 0.8mA.
In other word, the Neumann, and many other mics, are much less demanding in regard to the phantom supply, and will work flawlessly in situations where a 414 will be starved.
Since it has been hit, you may want to check the power consumption by measuring the voltage drop across the 6K8 resistors of a known good phantom psu.

Then I'd investigate the studio wiring between the happy and the mic box...

Axel

Click to expand...

thanks for the specs. just what I needed. Tested with a different 414 of the same model and  everything work including the 512's so it's down to that particular 414.

measure supply current? Easiest in the ground.