E-MU Tracker Pre USB 2.0 - Manual (Page 49)

Useful Information
TRACKERpre Reference Manual 49
USEFUL INFORMATION
Cables - balanced or unbalanced?
WARNING!
Balanced cables should
ONLY be used when
connecting to a device with
balanced inputs. Ignoring
this rule can actually
INCREASE noise and hum!
All inputs and outputs on the E-MU Tracker Pre are designed to use EITHER
balanced or unbalanced cables. Balanced signals provide an additional +6 dB of
gain on the inputs and are recommended for best audio performance, although
unbalanced cables work fine for most applications. If you’re having problems with
hum and noise, or just want the best possible performance, use balanced cables.
Balanced Cables
Balanced cables are used in professional studios because they cancel out noise and
interference. Connector plugs used on balanced cables are XLR (3-prong mic
connector) or TRS (Tip, Ring, Sleeve) 1/4" phone plugs.
Balanced cables have one ground (shield) connection and two signal-carrying
conductors of equal potential but opposite polarity. There is one “hot” or positive
lead and a “cold” or negative lead. At any point in time, both conductors are equal
in voltage but opposite in polarity. Both leads may pick up interference, but
because the interference is present both in and out of phase it cancels out at the
balanced input connection.
Unbalanced Cables
Unbalanced cables have one conductor and one ground (shield) and usually
connect via unbalanced 1/4" phone plugs or RCA phono plugs. The shield stays at
a constant ground potential while the signal in the center conductor varies in
positive and negative voltage. The shield completely surrounds the center “hot”
conductor and is connected to ground in order to intercept most of the electrical
interference encountered by the cable. Unbalanced cables are more prone to
ground loops, hum and interference than balanced cables, but the shorter the
cable, the less hum and noise will be introduced into the system.
Balanced 1/4”
TRS Connectors
Balanced XLR
Connectors
Unbalanced 1/4”
Connectors