Appendix B: Connections, Math And Stuff; Xlr Connectors; 1/4" Trs Phone Plugs And Jacks; 1/4" Ts Phone Plugs And Jacks - Mackie FRS Manual

Appendix B: Connections, math and stuff

Use a high-quality 3-conductor shielded cable to
connect the signal between the signal source (mixing
console, equalizer, etc.) and the balanced inputs to
the amplifier. If you are using unbalanced inputs, use a
high-quality 2-conductor shielded cable. Here are some
common audio connectors and their internal wiring:

XLR Connectors

XLR connectors are commonly wired as follows (ac-
cording to standards specified by the Audio Engineering
Society):
XLR Balanced Wiring
Pin 1 = Shield
Pin 2 = Hot (+)
Pin 3 = Cold (–)
1/4" TRS Phone Plugs and
Jacks
"TRS" stands for Tip-Ring-Sleeve, the three connec-
tions available on a stereo 1/4" or balanced phone jack
or plug. TRS jacks and plugs are used for balanced
signals and stereo headphones.
1/4" TRS Balanced wiring
Sleeve = Shield
Tip = Hot (+)
Ring = Cold (–)
1
FRS SERIES AMPLIFIERS
2
SHIELD
HOT
3 1
COLD
SHIELD 1
3
COLD 2
HOT
SHIELD
1
3 COLD
2
HOT
RING SLEEVE SLEEVE RING TIP
TIP
RING
TIP
SLEEVE
1/4" TS Phone Plugs and
Jacks
"TS" stands for Tip-Sleeve, the two connections avail-
able on a mono 1/4" phone jack or plug. They are used
for unbalanced signals.
1/4" TS Unbalanced Wiring
Sleeve = Shield
Tip = Hot (+)

Speakons

When using the Speakon outputs in stereo or mono
modes, wire the Speakon connectors as shown below:
Stereo and Mono Speakon Connection

Loudspeaker Cable

Note: Because of the high output capability of the am-
plifier, use only Class 3 (CL3) cable.
Use loudspeaker
Minimum AWG
cables with a mini-
mum conductor size
for the length you
need, as listed in
these tables.
This will minimize
power losses to less
than 0.5 dB. The
Min Metric WG 4 ohm
cable lengths listed
12
are "up to" lengths.
14
For in-between
16
lengths, use the next
larger conductor
20
gauge. Using larger
25
than the recommend-
ed conductor size is always permissible. Using smaller
than recommended conductor size will result in higher
power losses.
SLEEVE SLEEVE TIP
TIP
TIP
SLEEVE
1–
1+
COLD
1–
1+
2+
HOT
2–
4 ohm 8 ohm
18 10 ft 25 ft
16 25 50
14 25 75
12 50 125
10 100 200
8 ohm
3 m 8 m
8 15
8 25
15 40
30 60