Proel HPD2004 - Manuale (Pagina 12)

12
GENERAL INFORMATION
Thank you for having chosen a PROEL product.
HPD2004 and HPD4004 are 4-channel amplifi ers employing PROEL DA modules, a new genera on of digitally controlled
Class D power amplifi ers with Switch Mode Power Supply (SMPS) featuring an innova ve technology.
Unlike most of the class D amplifi ers, which use a fi xed switching frequency, the PWM (Pulse Width Modula on) output
stage of DA modules uses a variable switching frequency according to the input signal level.
Thanks to a sophis cated hardware and so ware structure, this system off ers performances far above most of the
products currently available on the market: be er sound defi ni on, high-fi delity reproduc on of any frequency of the
audio range, higher dynamics at any signal level with low distor on even at very high powers. The superior sound quality
can be compared with top-of-the-range AB-class analog systems, while DA modules thanks to the use of SMPS and Class
D feature very compact size and light weight, effi
ciency above 90% and negligible heat dissipa on.
The very high effi ciency levels result also in a signifi cant reduc on in the energy waste associated with large installa ons,
a no ceable reduc on in opera ng costs and a direct benefi t to the environment. Featuring high power levels in
a lightweight and compact chassis, the HPD amplifi ers are much easier and more economical to transport than
conven onal models and this, in turn, makes them even more environmentally friendly.
HPD amplifi ers include an input sec on with the choice of diff erent fi ltering op ons (FLAT / BI-AMP / HPF) and feature
an ergonomic and func onal design with removable dust fi lters, for an easy maintenance in all condi ons of use
and therefore extensive durability. The protec on system includes thermal protec on, short circuit protec on, high
frequency protec on and CLIP LIMITER circuit.
INSTRUCTIONS
1. Power switch
Amplifi er is "ON" when the switch is in the "I" posi on.
2. Power indicator
Blue LED: when lighted indicates amplifi er has been turned on and AC power is available for each module 1-2 and 3-4.
3. Channel LEVEL Control
Rotary level control: in STEREO and PARALLEL opera on it a enuates the level of the signal sent to the correspondent
channel of the amplifi er, while in BRIDGE opera on the channel control 1 or 3 operates as single control for the channel
pair set as bridge (1-2 or 3-4 respec vely).
The a enua on ranges from “∞” fully closed (the signal is completely a enuated) to “0” fully open, nominal level (the
signal is not a enuated in any way, so is fed to the amplifi er channel at the same level at which it arrives on input).
4. Channel SIGNAL Indicator
Green LED illuminates to indicate the presence of the signal at the correspondent amplifi er channel.
5. Channel LIMIT Indicator
Red LED illuminates when the channel's output is limited. When this LED fl ashes reduce the input signal level.
6. Channel PROTECT Indicator
Yellow LED illuminates when the correspondent channel is in protect mode for one of the following reasons:
• The heatsink reaches a temperature above the normal working limit.
• There is a short circuit at the amplifi er output wires.
• The amplifi er output stages are faulty.
Consequently the channel is muted un l the reason of fault is removed.
7. BRIDGE mode indicator
Yellow LED illuminates when the channel pair 1-2 or 3-4 is in bridge mode.
NOTE: When the channel pair operates in BRIDGE mode SIGNAL, LIMIT and PROTECT LED indicators illuminate
simultaneously, the signal is sent to each pair from channel 1 or 3 input only and controlled by channel 1 or 3 level
control only.