4
Operating Manual - Powerflex Multi-Channel Power Amplifier
1.
INTRODUCTION
The Ashly Powerflex amplifiers combine the effi-
ciency of a MOSFET high-speed switching output stages
with the sophistication of modern microprocessors and DSP
technology to produce a multi-channel amplifier with un-
precedented versatility and power in a single 3RU pack-
age.
Although similar to other amplifiers with class D
output stages, Powerflex amplifiers employ internal mi-
croprocessor and DSP algorithms to optimize output
switching characteristics and eliminate the usual harshness
associated with high-frequency audio in standard class D
amplifiers. This optimization results in a spread-spectrum
switched output that varies with input amplitude and fre-
quency, and minimizes radiated emissions by eliminating
the single-frequency high-energy radiated interference
normally associated with switching outputs. The use of a
simple linear power supply removes another potential
source of radio-frequency interference, an important con-
sideration as racks become more and more heavily popu-
lated with digital signal processing equipment. A small
switching supply using flyback topology provides an effi-
cient power source for logic, protection, pre-amplifier and
indicator circuits.
To assure reliable operation, the usual protection
from excessive high-frequency, DC offset, and thermal
overload is supplemented by power supply undervoltage,
power supply overvoltage, and output overcurrent detec-
tion, all monitored and controlled by the latest in minia-
turized microprocessor technology.
In sum, Ashly Powerflex amplifiers combine the
best of the new digital technologies with the best of the
traditional analog technologies to provide a product that
will supply clean sound at full output from every channel
while generating minimal heat, thus increasing the reli-
ability of every other piece of equipment in a rack as well
as preserving its own.
2.
UNPACKING
As a part of our system of quality control, every
Ashly product is carefully inspected before leaving the
factory to ensure flawless appearance. After unpacking,
please inspect for any physical damage. Save the ship-
ping carton and all packing materials, as they were care-
fully designed to reduce to minimum the possibility of
transportation damage should the unit again require pack-
ing and shipping. In the event that damage has occurred,
immediately notify your dealer so that a written claim to
cover the damages can be initiated.
The right to any claim against a public carrier can
be forfeited if the carrier is not notified promptly and if
the shipping carton and packing materials are not avail-
able for inspection by the carrier. Save all packing mate-
rials until the claim has been settled.
3.
AC POWER REQUIREMENTS
3.1
Voltage Requirements
The Powerflex amplifiers can be operated from
nominal 120VAC or 240VAC, 50/60Hz mains. This is user-
configurable by changing the insert in the AC Inlet (See
section 7.9). The power connector on the amplifier accepts
a standard IEC-320 receptacle.
For nominal 120VAC operation, the power cord
should be three-conductor, rated for at least 13A (16AWG).
The line fuse should be type MDA, 12A.
For nominal 240VAC operation, the power cord
should be three-conductor, rated for at least 10A (18AWG).
The line fuse should be type MDA, 10A.
3.2
Current Requirements
1.) Idle (no audio):
Powerflex 6250
Powerflex 4400
120V: 0.81A
120V: 0.9A
240V: 0.42A
240V: 0.5A
2.) With typical audio inputs:
8
Ω
loads on all channels
120V: 4A
120V: 4.6A
240V: 2A
240V: 2.3A
4
Ω
loads on all channels
120V: 6.5A
120V: 7.0A
240V: 3.3A
240V: 3.5A
70 Volt systems - (Powerflex 6250 Only,
3 channels Bridged Mono)
120V: 6.5A
240V: 3.3A
Powerflex amplifiers consumes less than 12 amps
when all channels operate at 1/8 power into rated (4 ohm)
loads. This condition satisfies the UL, CSA and building
electrical code requirements for a piece of audio equip-
ment not to consume more than 80% of the current avail-
able when plugged into a grounded 15 amp outlet and
operated at 1/8 of maximum power.
