-7-
Input Selector Switch
Once you have decided which input connectors you will use, set the input selector switches to their
Unbalanced or Balanced XLR position.
Speaker Connections
You may connect bare wire up to AWG 12, speaker wire terminated with 1/4" spade lugs, or banana plugs
to the five-way binding posts of your power amplifier. If you use bare wire without terminals, make sure
you remove only enough insulation so the wire can fit through the hole that runs sideways through the
terminal’s binding post. Before inserting the wire, twist all its strands tightly to prevent strays that could
cause a short circuit. (You may want to "tin" the stripped wire with solder to prevent it from fraying and
oxidizing.)
Bi-Wiring
The HCA-3500 is equipped with an additional set of binding posts to facilitate bi-wiring. These extra
speaker connectors are in parallel with the main binding posts. If your loudspeakers have two sets of
speaker connectors, you can bi-wire by connecting two sets of speaker cables from each channel of your
HCA-3500 to your speakers. Bi-wiring effectively reduces the lead resistance of your speaker wire thus
diminishing power loss and improving damping factor. The extra set of binding posts also make it easy
to connect an additional pair of speakers.
Observing Correct Polarity
When you connect speakers to your amplifier, you will notice that one side of the two conductor speaker
wire will have some sort of mark: either printing, a raised ridge on the insulation, or a different color of
conductor to let you know which wire to connect to the positive and which to the negative speaker
terminals so you can repeat the connection on the power amplifier's binding posts.
Minimum Speaker Impedance Precautions
Although the HCA-3500 is capable of driving speakers with occasional impedance dips well below
2
Ω
, it is primarily designed to drive loudspeakers with a 4
Ω
or 8
Ω
nominal impedance. This is because
sustained high power operation into loads of less than 4
Ω
may cause overheating and subsequent thermal
shutdown.
AC Power Connections and AC Grounding
Before you connect the AC cords, make sure the HCA-3500's power switches are in the off or down
position. If possible, plug your amplifier directly to an AC wall outlet. Be sure to plug both AC cords into
the same outlet help prevent possible ground loops. Do not connect the AC cords to the accessory AC
outlet on your preamplifier because the amplifier's current draw exceeds the ratings of most preamplifier’s
power switches and power cords. If you use an external AC line conditioner or surge suppressor, make
sure it can withstand the HCA-3500's power requirements listed in the specification section of this
manual.
