Hello!
I'm a tech. with a grounding question for Keith. [EDIT: For anyone, I would have hoped... -After all, asking only one person's opinion doesn't give a full picture, after all! -Keith]
I've seen several different ways that shields are terminated to/from a patchbay, and I was wondering what type of ground/shield configuration that you use?
One studio I worked at had the shields lifted at the signal wire's point of entry , and the system would develop the "creeping hum".(This phenomenon would start as an almost immeasurable 120Hz noise, then over a period of days would become intolerable. Powercycling the power on all equipment would solve it temporarily--until it became audible again.) I verified the problem as ground currents on the shields, but the studio owner didn't want to pay to rewire the studio. It was cheaper to powercycle the equipment everyday... : (I probably should mention that this studio had electronically balanced gear--no transformers, and an improper residential type electrical service with redundant grounds and no clean technical ground.)
A similar setup had CB radio rip everybody's head off whenever a trucker that was passing by flipped the switch. I spun the wheel, gambled, and rewired that studio per AES recommendations,had the power service rewired,and the CB radios went away.I guess I got it right... :-\
There seems to be so many camps of grounding procedures, and you have obviously been in the field getting it right, I would really like to hear your thoughts and recommendations regarding shield termination at and to/from the patchbay.
Thank you for your help!
I'm a tech. with a grounding question for Keith. [EDIT: For anyone, I would have hoped... -After all, asking only one person's opinion doesn't give a full picture, after all! -Keith]
I've seen several different ways that shields are terminated to/from a patchbay, and I was wondering what type of ground/shield configuration that you use?
One studio I worked at had the shields lifted at the signal wire's point of entry , and the system would develop the "creeping hum".(This phenomenon would start as an almost immeasurable 120Hz noise, then over a period of days would become intolerable. Powercycling the power on all equipment would solve it temporarily--until it became audible again.) I verified the problem as ground currents on the shields, but the studio owner didn't want to pay to rewire the studio. It was cheaper to powercycle the equipment everyday... : (I probably should mention that this studio had electronically balanced gear--no transformers, and an improper residential type electrical service with redundant grounds and no clean technical ground.)
A similar setup had CB radio rip everybody's head off whenever a trucker that was passing by flipped the switch. I spun the wheel, gambled, and rewired that studio per AES recommendations,had the power service rewired,and the CB radios went away.I guess I got it right... :-\
There seems to be so many camps of grounding procedures, and you have obviously been in the field getting it right, I would really like to hear your thoughts and recommendations regarding shield termination at and to/from the patchbay.
Thank you for your help!