Post by Deleted on Dec 18, 2013 10:04:05 GMT -6
Well,
thread title says it....
As far as i understand, synths generally have an unbalanced output of -10dBV RMS and a more or less weak or undefined maximum load they can drive..........
So there is 2 problems interconnecting them with a modern AD with pro level input.
First, the conversion unbalanced out to balanced in, second, the level difference.
My approach now is the following....:
The signal's volume drop between synth out and AD in is 12dB, which in my understanding is not as critical, as it may sound. So i think, it may be not necessary or essential to make a volume level matching with active circuitry at all...
So i primarily see the need of noise rejection, especially for a few meters of cable run in a modern (computerized) environment.
I know, many people just interface with a cable, optimally shielded twisted pair, like cold and shield both connected to the ring at the unbalanced side / in the TS-plug....
While this may not work bad at all, and takes advantage of the balanced in at the AD for noise rejection, there could be an improvement by ground isolation (especially at long cable run there might be problems with mains ground potential differences...).
So i see two ways to do this. (Assuming the AD is NOT transformer balanced in....)
One would be to ground isolate with a 1:1 line level input transformer like the Lundahl LL1540 wired 1:1 at the ADs end, still using above mentioned cable for the long run.
The second solution i see is to ground isolate and balance at the synth's end with a 1:1 line level output transformer like the Lundahl LL1539 - which seems to be a much better solution, because the long cable run is fully balanced then.
I would like to do this with a small portable passive transformer box...so i can connect it flexibly to any piece of consumer level output gear with a short unbalanced cable....(well, these transformers are not particularly cheap.....)
Fortunately, i have a pair LL1539 in the drawer....
Does anybody see a showstopper, why this will not be a good idea?
Did i overlook something essential (sometimes i can't see the forest by the trees.....)?
Best regards,
Martin
thread title says it....
As far as i understand, synths generally have an unbalanced output of -10dBV RMS and a more or less weak or undefined maximum load they can drive..........
So there is 2 problems interconnecting them with a modern AD with pro level input.
First, the conversion unbalanced out to balanced in, second, the level difference.
My approach now is the following....:
The signal's volume drop between synth out and AD in is 12dB, which in my understanding is not as critical, as it may sound. So i think, it may be not necessary or essential to make a volume level matching with active circuitry at all...
So i primarily see the need of noise rejection, especially for a few meters of cable run in a modern (computerized) environment.
I know, many people just interface with a cable, optimally shielded twisted pair, like cold and shield both connected to the ring at the unbalanced side / in the TS-plug....
While this may not work bad at all, and takes advantage of the balanced in at the AD for noise rejection, there could be an improvement by ground isolation (especially at long cable run there might be problems with mains ground potential differences...).
So i see two ways to do this. (Assuming the AD is NOT transformer balanced in....)
One would be to ground isolate with a 1:1 line level input transformer like the Lundahl LL1540 wired 1:1 at the ADs end, still using above mentioned cable for the long run.
The second solution i see is to ground isolate and balance at the synth's end with a 1:1 line level output transformer like the Lundahl LL1539 - which seems to be a much better solution, because the long cable run is fully balanced then.
I would like to do this with a small portable passive transformer box...so i can connect it flexibly to any piece of consumer level output gear with a short unbalanced cable....(well, these transformers are not particularly cheap.....)
Fortunately, i have a pair LL1539 in the drawer....
Does anybody see a showstopper, why this will not be a good idea?
Did i overlook something essential (sometimes i can't see the forest by the trees.....)?
Best regards,
Martin