Tropicalista
New member
- Joined
- Mar 12, 2021
- Messages
- 3
Hello all,
After some time reading and researching this brilliant resource I’m posting my first post and looking for some advice.
I am working on a 1968 Neumann Recording Console that has a number of PV46sd line cards.
I have replaced the Electrolytic capacitors.
When on the bench they test good and have around 40 to 45db of gain. However I have two questions:
1. What does R27 do? It is a 5K trimmer. When I adjust it, the THD/Noise rises from 0.05% to 4% and it adjusts the volume by around 1db
2. All of the cards have 300 Ohm resistors at R11 & R12, but they all have slightly different output levels, ranging from 40db to 45db. Is this normal or is there
a possible component failure? Resistors test good with a multi meter. Trimmers test good.
Any help or suggestions would be greatly appreciated.
Thanks!
Will
After some time reading and researching this brilliant resource I’m posting my first post and looking for some advice.
I am working on a 1968 Neumann Recording Console that has a number of PV46sd line cards.
I have replaced the Electrolytic capacitors.
When on the bench they test good and have around 40 to 45db of gain. However I have two questions:
1. What does R27 do? It is a 5K trimmer. When I adjust it, the THD/Noise rises from 0.05% to 4% and it adjusts the volume by around 1db
2. All of the cards have 300 Ohm resistors at R11 & R12, but they all have slightly different output levels, ranging from 40db to 45db. Is this normal or is there
a possible component failure? Resistors test good with a multi meter. Trimmers test good.
Any help or suggestions would be greatly appreciated.
Thanks!
Will