TL Audio 5021 - Manual (Page 8)

The 5021 may be used to shift operating levels, for example by connecting the
unbalanced output of a semi-pro mixing console to the 5021’s unbalanced
input, and taking the balanced output of the 5021 to the balanced input of a
tape machine at +4dBu. All line-level inputs and outputs of the 5021 may be
used simultaneously if required. Balanced interconnection is always preferable
to obtain the best headroom and noise rejection, but can only be used
effectively if the other equipment in the chain, e.g. the mixing console, also
has provision for balanced connections.
3.3
Balanced Line Input.
The line level input is via a 3 pin female XLR connector, suitable for balanced
or unbalanced line sources at a nominal level of +4dBu. The mating
connector should be appropriately wired as follows for balanced or unbalanced
operation:
Balanced inputs:
- Pin 1 = Ground (screen).
- Pin 2 = Signal Phase (also known as “+” or “hot”).
- Pin 3 = Signal Non-Phase (“-” or “cold”).
Unbalanced inputs:
- Pin 1 = Ground (screen).
- Pin 2 = Signal Phase (“+” or “hot”).
- Pin 3 = Signal Ground.
When using unbalanced signals into the balanced XLR input, the signal
ground may be obtained by linking pins 1 and 3 in the mating XLR connector.
If this connection is not made, a loss in level may result.
3.4
Unbalanced Line Input.
An unbalanced line level input at a nominal level of -10dBu is also provided,
on a 0.25” mono jack socket. The mating plugs should be wired as follows:
- Tip = Signal Phase (“+” or “hot”).
- Screen = Ground.