RFSiesta
Well-known member
Hello,
We have an old Trident 80B in the studio and tried two V672 amps for summing - with astonishing results, soundwise.
The only issue that's hard to adress is to get those as clean as possible.
I used a pretty clean, but homemade PSU, will try with a mint condition Telefunken 24V supply next, but I doubt it's the PSU that is responsible for a little hum, noise and a 1k "peep" that's coming with the signal.
I was able to reduce it by trying different connections to ground, but it's still there.
It's not very much, but enough to stop the show for me
question I have is:
How much of a problem is it to send a non-balanced summing bus to a balanced summing amp with transformers at the input?
The V672 have an input impedance of >2Ω, which is NOT zero. So a little bit of voltage will drop over the input, which may or may not be a problem. The original summing board has very close to zero Ω at the input, and summing ground is connected as short as possible to the PCB ground.
Any suggestions?
Thank you!
best
Richard
We have an old Trident 80B in the studio and tried two V672 amps for summing - with astonishing results, soundwise.
The only issue that's hard to adress is to get those as clean as possible.
I used a pretty clean, but homemade PSU, will try with a mint condition Telefunken 24V supply next, but I doubt it's the PSU that is responsible for a little hum, noise and a 1k "peep" that's coming with the signal.
I was able to reduce it by trying different connections to ground, but it's still there.
It's not very much, but enough to stop the show for me
question I have is:
How much of a problem is it to send a non-balanced summing bus to a balanced summing amp with transformers at the input?
The V672 have an input impedance of >2Ω, which is NOT zero. So a little bit of voltage will drop over the input, which may or may not be a problem. The original summing board has very close to zero Ω at the input, and summing ground is connected as short as possible to the PCB ground.
Any suggestions?
Thank you!
best
Richard