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Placement of Your HCA-1206
Place your HCA-1206 away from heat sources such as hot air ducts or radiators. Make sure that your
cabinet or shelf can support its enormous weight. Always place your unit horizontally. Do not place your
unit directly on a carpet whose pile could interfere with air flow into its bottom vent openings or heat
sinks. If you place your HCA-1206 on the floor near your speakers, elevate it above the pile of the
carpet. If you stack your components, it is better to place your HCA-1206 alongside other components.
Rack Mounting Your HCA-1206
Your HCA-1206 can be mounted into a standard EIA 3 unit 19" rack. Make sure you select heavy duty
mounting bolts and nuts and use washers under the heads of the bolts to avoid scratching your amplifier’s
anodized front panel. Do not attempt to hold your unit in place yourself while you attach the bolts and
nuts. Have a strong helper support the unit as it is being attached to the rack. The heat generated by the
HCA-1206 may require a fan to assist air flow and if you have another component mounted directly
above it in the rack.
Ventilation Requirements for Your HCA-1206
Your Parasound power amplifier is designed to operate with high idling, or bias, current to reduce higher-
order harmonic distortion. This bias optimization is characteristic of all Parasound power amplifiers and
is perfectly normal, but it results in noticeably warm operation even when no signal is present. While
many other amplifiers manufacturers have chosen to bias their amplifiers at a lower level to run cooler,
we bias our amplifiers so the output transistors are allowed to operate in a much more linear region.
Although the amplifier may run a little warmer than other amplifiers, we feel the resulting sonic
improvements are significant and justified.
However, to insure safe and reliable operation, it is very important that the amplifier has plenty of
ventilation to prevent overheating and automatic shut down from the thermal protection circuitry.
Please observe the following guidelines when installing your Parasound power amplifier:
1. If you are not using a fan, allow at least six inches on each side and above the amplifier, and
do not close off the front with a door or panel.
2. If you are enclosing the amplifier in an equipment cabinet, use a fan and draw in cool air or
exhaust warm air. In either case, two vent holes are required: one for intake and one for exhaust.
3. Do not place the amplifier on carpeting which will obstruct the air flow from the bottom of the
amplifier.
4. If you plan on stacking amplifiers, you must use a fan.
Minimum Impedance Precautions
You may connect loudspeakers with a 4
Ω
or 8
Ω
nominal impedance for unbridged operation. Your
HCA-1206 is capable of driving speakers with occasional impedance dips well below 2
Ω
. However,
Lower nominal impedance loads are not recommended and may cause overheating.
The HCA-1206 is designed for a minimum 8
Ω
nominal impedance for each speaker connected to
bridged channels 3+4 or 5+6. Use of lower impedance at high listening levels may cause overheating or
trigger one of the amplifier's protection circuits.
These restrictions result from the mathematics of the bridging circuitry. In the bridge mode each channel
of the amplifier functions for only the + or — half of the musical waveform. Thus, each channel "sees"
only half of the speaker’s impedance. Use of an 8
Ω
speaker means that the load for each channel is
4
Ω
. And for a 4
Ω
speaker, it would result in only 2
Ω
.