Let me try to clear up a few things.
A balanced signal does not include a "hot" and "cold" signal - even though they are sometimes described that way.
The (+) signal is a full level in-phase signal and the (-) signal is a full level signal that is inverted (exactly 180 degrees out of phase with the first).
At the input those two signals are subtracted (remember that subtracting a negative value is the same as adding a positive value).
The result is an output signal that is TWICE the level of the in-phase input signal.
The idea is that any noise that impinges on both wires at the same time will be added to both.
Then, when you subtract the two signals....
The desired (+) signal, minus the desired (-) signal, gives you TWICE the desired signal.
But the undesired noise signal (on the + line), minus the undesired noise signal (on the - line), cancels out... and the noise mostly goes away.
This is the main reason why balanced connections are used.
(Certain distortions that might arise in the output and input circuitry may also cancel out.)
While it's true that some people consider the levels involved "so obvious they don't bother to mention them"....
It's also true that, since the main purpose of a balanced connection is NOT "to give you a higher level signal", not everyone treats it the same.
On some equipment, the two lines of a balanced connection do each carry a signal at the same level as a single unbalanced connection...
However, on a lot of gear, especially consumer gear, the balanced outputs and inputs operate at the higher "pro level", while the unbalanced inputs and outputs operate at a lower "consumer level".
And, on a lot of home audio gear, both lines of the balanced inputs and outputs operate at the lower "consumer level", which still provides the benefit of noise immunity.
And, because, of this, in some gear, the two signals in the balanced connections are subtracted as they should be, then the result is divided by two, to produce a lower level "safer" signal.
You will also find similar disagreement on what the "standard level" of an unbalanced signal "should be"...
There are "standards" that call for 0.770V, 1.0V or 2.0V ... and there is no single obligatory standard.
Therefore, most outputs are designed to be able to deliver enough voltage to satisfy any of those requirements...
And most analog inputs are designed with enough gain to work with most of those levels as well.
(You will also find that most consumer gear specifies an "output level" and a "MAXIMUM output level" - which is much higher - to cover that range of possibilities.)
Most two-channel analog preamps are set up in such a way that their analog inputs can handle much higher voltages.
In a typical analog stereo preamp, you have a passive Volume control first, followed by an active gain stage, which together can tolerate very high input voltages with no problem.
HOWEVER, in typical home theater gear, the input is immediately digitized, at which point you may have to worry about overloading the input ADC circuitry, which may occur at only 2V or so.
I am not going anywhere with this because my question has been answered, I just wanted to explain better to gregorio what I meant.
You didn't get what it was all about? The DSP 4x4 Mini's I was talking about have balanced inputs and outputs (that I use unbalanced but that doesn't change the question or the answer). My question was about balanced inputs. The voltage specification could have been interpreted in 2 different ways as I explained. I briefly tried to google it before but apparently it is one of those things that everyone finds so obvious that they never mention it.