Connecting unbalanced source to balanced input using balanced cable & noise rejection

[Scoox]

I need a 1U rack-mount mixer in my studio and I'm considering the BEHRINGER RX1602 V2, which is perfect for my needs but there is a slight snag: it has unbalanced outputs. However, the audio interface that it would be connected to (RME UCX II) has balanced inputs, so does that even matter?

My reasoning is that if I connect an unbalanced source to a balanced input using a balanced cable, the ring contact would be unconnected at the source, but still connected at the balanced input, so any electromagnetic noise arriving at the balanced cable would affect both the ring and the tip wires equally, therefore the balanced input would get two identical noise signals that would cancel out, leaving just the clean audio signal from the tip wire. The only slight drawback is that the signal would be 6 dB quieter, but I can crank up the gain to fix that. Of course the reverse wouldn't work, in other words, connecting a balanced output to an unbalanced input, since the noise rejection action happens at the input.

I have a sneaking suspicion there are holes in my theory and I wanted to run it past people with a better understanding than me. The other thing I'm not sure about is how the outputs of this mixer are connected internally (it could be a TS socket but it could also be a TRS socket with one pin connected or unconnected) and whether my UCX II will treat the signal as balanced or unbalanced.

 

[JayGilb]

This is from the link you posted and it shows that the Master outs are balanced.

 

[Vincent Kars]

using a balanced cable

The cable isn't balanced. It has a certain number of wires.
If you have 3 wires, you can send a hot (the signa), a cold (the inverse of the signal) and a ground.
At the receiver the cold is flipped again and now the 2 are compared. Any difference is considered noise. This is how common noise reaction works.
You can't do this with a SE signal.

 

[Scoox]

View attachment 244386

This is from the link you posted and it shows that the Master outs are balanced.

Interesting, I wonder if the specs I was looking up was for the earlier V1 model. The thing is, I've just checked the user manual for V2 and, while it says the inputs are definitely balanced, it doesn't explicitly or implicitly state that the outputs are balanced. I'm not 100% sure the info in that screenshot isn't an error. The Sound On Sound review says they are unbalanced, although it's a review of the old V1 model.

Edit: This guy says the new model apparently has balanced outputs.

 

[JayGilb]

Interesting, I wonder if the specs I was looking up was for the earlier V1 model. The thing is, I've just checked the user manual for V2 and, while it says the inputs are definitely balanced, it doesn't explicitly or implicitly state that the outputs are balanced. I'm not 100% sure the info in that screenshot isn't an error. The Sound On Sound review says they are unbalanced, although it's a review of the old V1 model.

Edit: This guy says the new model apparently has balanced outputs.

I downloaded the v2 user manual and the Master outs were labeled as TRS which indicates a balanced topology.

 

[Scoox]

I downloaded the v2 user manual and the Master outs were labeled as TRS which indicates a balanced topology.

Yeah but it doesn't say "balanced". Actually, the SOS review of the V1 model says

All the connections are on the rear panel, where you'll find 16 balanced TRS jack line inputs arranged as eight stereo pairs, two main outs on TRS jacks (these are specified as being unbalanced, even though they are on TRS jacks), and a single aux send buss.

 

[AnalogSteph]

Making an output impedance-balanced is so cheap that this is the minimum standard I would be expecting. It doesn't have to be a "proper" balanced output. The input side is the more important part anyway.