esponsible for its content.
Operating Manual MFA-8000
MFA-6000
Power Amplifier
Operating Manual
ASHLY AUDIO INC.
847 Holt Road Webster, NY 14580-9103 Phone: (716) 872-0010
Toll-Free: (800) 828-6308 Fax: (716) 872-0739 Internet: http://www.ashly.com/
Off
On
0(Clip)
-3
-6
-9
-12
-15
-18
-21
-24
-27
-30
Dual Monaural Amplifier
Channel One Output Level
Limit
Thrm
Protect
AC Power
0(Clip)
-3
-6
-9
-12
-15
-18
-21
-24
-27
-30
Channel Two Output Level
Limit
Thrm
Protect
MFA-6000
Off
On
0(Clip)
-3
-6
-9
-12
-15
-18
-21
-24
-27
-30
Dual Monaural Amplifier
Channel One Output Level
Limit
Thrm
Protect
AC Power
0(Clip)
-3
-6
-9
-12
-15
-18
-21
-24
-27
-30
Channel Two Output Level
Limit
Thrm
Protect
MFA-8000 Operating Manual - MFA-8000 and MFA-6000 Power Amplifier
2
Table Of Contents
1
INTRODUCTION
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2
UNPACKING
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3
AC POWER REQUIREMENTS
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.1 AC Voltage Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.2 Current Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.3 AC Grounding Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4
CABLE REQUIREMENTS
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.1 Input Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.2 Output Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
5
RACK-MOUNTING REQUIREMENTS
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
5.1 Mechanical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
5.2 Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
6
FRONT PANEL FEATURES
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
6.1 Power Switch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
6.2 Output Meters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
6.3 Clipping Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
6.4 Limit Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
6.5 Thermal Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
6.6 Protect Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
7
REAR PANEL FEATURES
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
7.1 Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
7.2 Normal/Bridging Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
7.3 Stereo/Parallel Mono Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
7.4 Level Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
7.5 Speaker Outputs - Binding Posts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
7.6 Speaker Outputs - Speakon Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
8
INPUT OPTIONS
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
8.1 Input Isolation Transformer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
8.2 Peak Limiter Compressor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
8.3 Two-Way Crossover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
8.4 Mic-Line Mixer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3
Operating Manual - MFA-8000 and MFA-6000 Power Amplifier

Caution:
This power amplifier can produce dangerous output voltage
levels, high power levels, and high sound pressure levels in
loudspeakers. In order to minimize the risk of injury, damage, or
hearing loss, please read the entire owner's manual before connecting
to a sound system.
9
TYPICAL APPLICATIONS
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
9.1 Stereo Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
9.2 Parallel Mono Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
9.3 Bridged Mono Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
10 DESIGN THEORY
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
11 TROUBLESHOOTING TIPS
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
11.1 No Audio Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
11.2 Distorted Sound . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
11.3 Hum or Buzz Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
12 DIMENSIONS
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
13 SPECIFICATIONS
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
14 WARRANTY POLICY
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Operating Manual - MFA-8000 and MFA-6000 Power Amplifier
4
1.
INTRODUCTION
The MFA Series amplifiers achieve the very high
energy levels used in todays professional sound systems,
carefully maintaining control and accuracy while deliv-
ering high power to modern loudspeaker configurations.
The MFA 8000 (MFA 6000) will deliver 1200 Watts
(800W) per channel into 4 , and up to 3000 Watts
(1800W) bridged-mono into 4 . They are Ashly Audios
highest-powered amplifiers, employing an advanced
power supply circuit capable of delivering continuous high
current to the most demanding loads. The MFA amplifi-
ers have a dual-monaural design with completely inde-
pendent, yet physically identical channel modules, offer-
ing superior audio performance, better weight distribu-
tion, and greater reliability. In order to fully benefit from
the many features designed into this product, please take
time to read this entire manual before operating.
Caution: This product can deliver enough
energy to the output terminals to produce a lethal
shock. Do not attempt to wire the amplifier when
the power is turned on.
Caution: The MFA amplifiers are capable
of delivering tremendous amounts of power to the
speaker load. Ashly Audio is not responsible for
speaker damage as a result of excessive power.
Caution: This unit is capable of produc-
ing high sound pressure levels. Continuous expo-
sure to high sound pressure levels can cause per-
manent hearing impairment or loss. Use caution
when operating at high levels by wearing appro-
priate ear protection.
The MFA amplifiers employ complimentary bi-
polar output transistors to achieve maximum output cur-
rent capability and power efficiency. All voltage gain
and current gain stages remain completely discrete and
fully complimentary for lowest distortion and superior
overload behavior.
In addition to the amplifiers audio path, several
sophisticated monitoring and control circuits serve to keep
the amplifier running comfortably within its safe operat-
ing area, while protecting the speaker loads from abnor-
mal conditions. This protection will intelligently respond
to hard clipping, overheating, excessive high frequency
energy, and output DC, thus preventing damage to the
amplifier or the load. Status LEDs indicate fault condi-
tions, if any, and warn the operator of situations requiring
a change in operating environment.
The MFA amplifiers are compatible with all Ashly
Powercard input options, and are shipped standard with
balanced XLR, 1/4" TRS and screw terminal input con-
nections, as well as 5-way binding post and Neutrik
Speakon speaker connections. Stereo, parallel mono, and
bridge mode switches along with a ground lift are all ex-
ternally accessible on the back panel.
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