Numark SA3000 Bedienungsanleitung
Owner’s Manual
SA3000/SA5500/SA9500
Amplifiers
©1997 Numark Industries http://www.numark.com
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©1997 Numark Industries http://www.numark.com
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SAFETY FIRST!
WARNING - TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK, DO NOT EXPOSE THIS
APPLIANCE TO RAIN OR MOISTURE.
WATER AND ELECTRICITY DO NOT MIX. Keep this unit away from water. If water or other liquids are
spilled on or into this unit, unplug the power cord immediately from the wall socket (with DRY
HANDS) and get a qualified service technician to check it out before using. Keep this unit away from
heaters, radiators and other heat producing devices.
DO NOT ATTEMPT TO SERVICE THIS UNIT. ONLY A QUALIFIED SERVICE TECHNICIAN SHOULD OPEN
THIS UNIT FOR SERVICING.
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
The lightning flash with arrowhead symbol within an equilateral triangle is intended to alert the user to the presence of uninsulated 'dangerous
voltage' within the product's enclosure that may be of sufficient magnitude to constitute a risk of electric shock.
The exclamation point within an equilateral triangle is intended to alert the user to the presence of important operating and maintenance
(servicing) instructions in the literature accompanying the product.
CAUTION: TO REDUCE THE RISK OF ELECTRIC SHOCK, DO NOT REMOVE
COVER (OR BACK). NO USER-SERVICEABLE PARTS INSIDE. REFER
SERVICING TO QUALIFIED SERVICE PERSONNEL.
KEEP IT CLEAN: Dust, dirt and debris can interfere with the performance of this product.
Make a special effort to keep this unit away from dusty, dirty environments. Cover the unit
when not in use. Dust it regularly with a soft, clean brush. Careful attention to these
details will be time well spent, and this product will reward you with years of trouble free
operation.
Please take the time to read this manual before use. Store this
manual in a safe place so that it is available should you ever
need it again.
©1997 Numark Industries http://www.numark.com
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©1997 Numark Industries http://www.numark.com
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Contents
Warning and Safety Instructions 3
Introduction 6
Front-Panel Description 7
Back-Panel Description 8
Audio Terms 10
Hook-up #1: Home Studio Reference Amp 12
Hook-up #2: Mobile DJ Stereo PA 12
Hook-up #3: Monitor Amplifier 13
Hook-up #4: Stereo PA System 13
Specifications 14
Block Diagram 15
Warranty and Service Information 16
©1997 Numark Industries http://www.numark.com
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Introduction
Thank you for choosing a Performance Series power
amplifier from Numark. These units are designed to
provide a good combination of power, audio clarity,
and reliable operation. The basic circuit has been
kept as simple as possible to reduce the amount of
components, thereby shortening the signal path,
coloration and the chance of component failure.
However, we opted to add what we regard as
essential protection against overheating, short
circuits and power on transients.
An efficient heat dissipation system, comprising a
high surface area heatsink coupled with one or two
fans (depending on power rating of amp), ensures
quiet and reliable cooling.
The sound quality and sturdy construction of the
Performance Series makes these amps ideal for a
multitude of amplification tasks, from installations,
mobile DJs, home studios, houses of worship and
touring bands.
Since all of the amplifiers are similar in operation, this
manual serves for all models. Please take the time
to read this manual before connecting and operating
your unit, as there is important information contained
within. File the manual in a safe place for future
reference.
©1997 Numark Industries http://www.numark.com
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Front Panel Description
1. Gain Controls
These two knobs are the level controls for each channel
of the amplifier. The gain increases as the knob is turned
clockwise. The SA5500 features detented gain controls
with dB calibrations to simplify set up.
2. Limit LED
If an audio signal is amplified beyond the limit of the
amplifier, the extremes of the signal will not reach the
appropriatelevels,givingtheappearanceofbeingclipped
off when viewed on an oscilloscope. The audible result is
distortion, which in small amounts can lead to rapid ear
fatigue, and in larger amounts a harsh and unpleasant
breakingupofthesoundwhich can damage speakers.
The SA5500 has a built in limiter on each channel to
prevent clipping. Should the signal reach a level high
enoughtocauseclipping,thelimitermomentarilyreduces
the level just enough to prevent it. The limit LED lights
whenever this occurs.
If your system has a dedicated compressor, you may
decidetousethelimitingfunctionofthisinstead.Although
thelimitingfunctionoftheSA5500 has nonoticeableeffect
on the sound quality below clipping, some users may
seektodisableit.Seefeature11.
3. Protect LED
The SA5500 features several types of protection to
prevent damage to the circuitry during turn on or fault
conditions. The power on protection relay prevents
damaging thumps to the speakers as the power comes
on. When the amp is switched on, the protect LED will
lightforafewsecondsand then go out, indicating that the
relay has closed, connecting the speakers to the
amplifier.
Theprotectlight will also come on if the speaker terminals
are short circuited, or the impedance of the load between
them is too low. In these circumstances, the protect LED
willstaylituntil the fault condition is rectified.
The amplifier’s large heatsinks, vents and fan should
provide enough cooling even with a high ambient
temperature. However, if the amp overheats, thermal
shutdown protects the circuitry until the temperature is
reduced to a safe level. Should the amp shutdown for
thermal reasons, leave the power connected to the amp,
try to improve ventilation, and reduce the gain. Without
power, the fan cannot operate, and the amp will require
longerto reach alowenoughtemperature to restart.
4. Signal LED
Each channel of the SA5500 features a signal LED to
show that there is an audio signal at the input to the
channel. The threshold for the indicator is -30dB, which
shouldbe enough that noisedoesn’ttrigger the LED, but a
faintaudiosignal will.
5. Power Switch
This turns the amp on and off. Although the SA5500
featurespoweronmuting,itisneverthelessgoodpractice
toreduce both thegain controls beforeturningon the amp.
The turn on procedure for powering up an audio system
should be to start from the instruments and mixer, and
verify operation before moving on to the power amps.
Once the amps are on, verify they are receiving a signal
and then slowly increase gain.
©1997 Numark Industries http://www.numark.com
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Back Panel Description
6. Neutrick Connector Inputs
a.Balanced XLR Inputs
These combined inputs are commonly used for both
mobile and installation set ups. The XLR provide a good
combination of ease of connection and resistance to
corrosion. They are wired as per the following
convention:
b. Balanced 1/4” Inputs
These types of jacks are featured on many audio
products and are convenient if the amp is frequently
connectedanddisconnected,suchasforamobilesetup.
The plugs used should be wired in the following way:
ring
tip sleeve
+ - gnd
7. Balanced Barrier Strip Inputs
These connection points provide the best option for
permanent or long term installation. Connections should
be screwed down tightly to exclude oxygen, and care
should be taken to avoid loose strands of wire that may
causeshort circuits.
+ - GND - +
8. Binding Post Outputs
speaker speaker
+
-
BRIDGED MONO
These are suitable for banana plugs, spade lugs or bare
wires. Spade lugs and bare wires should both be
screwed down tightly to exclude oxygen, and care
should be taken to avoid loose strands of wire that may
causeshort circuits.
9. Ground Lift Switch
This switch allows the circuit and chassis grounds to be
separated in case of a ground conflict. In normal use the
switch should be in the ‘ground on’ position. Lifting the
ground (‘floating’ position) may resolve the ground
conflict,but means thatcircuitgrounding depends onother
connected components. Deficiencies in the grounding of
other components will affect the sound. A serious electric
faultwiththeamplifiercould damage other components in
the system. For the best combination of safety and
performance it is highly recommended to keep the switch
inthe ‘ground on’ position.
10. Stereo / Mono Bridge Switch
In stereo operation, each channel of the amplifier runs
independently with its own signal and speaker(s).
However, both channels can be configured to drive a
single load with a single signal at twice the power.
Todothis, follow these steps:
1. switch the amp OFF
2. put one speaker of not less than 4 ohms impedance
acrossthe red (+) output terminalsofthe amplifier
©1997 Numark Industries http://www.numark.com
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3. ensure that there is only one input signal connected
tochannel 1 of the amplifier - channel 2 inputmustbe
vacant
4. switch the amplifier to bridged mono (back panel
switch)
5. turn the gain down and turn on the amp
6. verify operation at low gain, and then increase power
to desired level, ensuring that the gain controls on
eachchannel are set equally.
IMPORTANT: NEVER SWITCH BETWEEN
STEREO AND BRIDGED MONO OPERATION
WHEN THE AMPLIFIER POWER IS ON.
11. Limiter On / Off Switch
In cases where a dedicated compressor / limit unit
precedes the SA5500, some users may seek to disable
the on board limiting. Sliding the switch to the off position
removesthe limiting from both channels of the amplifier.
©1997 Numark Industries http://www.numark.com
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Audio Terms
Gain
This is the factor by which an input signal is amplified
(increased)or attenuated (reduced) whenpassingthrough
an amplifier. Gain is generally measured in decibels (dB)
which is a logarithmic ratio of input to output. Unity or
zero gain means that the signal comes out at the same
level that it went in.
With all this gain available, it may seem tempting to turn
the amp up to full to get the loudest sound possible. And
why is it that smaller amps have roughly the same gain
even though they are less powerful? The answer is that
an amp can only amplify up to a certain point, which
depends on its power rating. Past this point, the output
just distorts in what is called clipping. The peaks of the
signal are ‘clipped’ as they exceed the limit.
max+
max-
max+
max-
#1. Peaks within amplifier limit
#2.Too much gain, distorted sound
Noise
Noise is typified by a hissing sound. It is present in all
analogue electronics due to random thermal vibration of
atoms within the components. However, good circuit
designand proper operation reduces this toaminimum.
Gain structure, i.e. how gain is set throughout the signal
path, is very important in minimizing noise. Most audio
signalsgothrough several gain stages such as input trim,
fader gain, main fader gain, EQ and compressor gain,
and power amplifier gain. If the signal is boosted early on
to a high level, any noise subsequently picked up will be
relatively small in comparison to the audio signal (i.e.
higher S/N, or sound to noise ratio).
If the gain is low early on, the noise will be
relatively loud compared to the signal. When
amplified at the power amp more gain must be
used to make the signal reach required levels.
This gain also acts on the noise, hence a noisier
final sound. Of course, care must be taken not to
set the gain too high, this will cause clipping
distortion(seefirst section on ‘Gain’).
Hum and Buzz
Hum typically is a lower pitched sound of around 50 or
60Hz, depending on the AC supply. If the hum or buzz
is very loud, this is generally caused by bad connections
-check cables and plugs for faults.
Lifting the Ground
Inothercases,a ground conflict between the chassis and
the circuit ground can induce hum. This happens when a
magneticfieldinducesa small voltage in the casing of the
amp,makingitslightlydifferentinpotentialfromthecircuit
ground.Thishumsoundsmoresubtlethanitwouldbefor
a bad connection and is generally ignored. If your
environmentrequires the highest quality sound, it may be
eliminated by ‘lifting the ground’. This is accomplished by
moving the back panel switch from the ‘ground on’
position to the ‘floating’ position. The electronic ground is
thendependent on other connected components. For the
bestsafety protection and protection ofothercomponents,
it is strongly advised to keep the switch in the ‘ground on’
position.
Balanced Lines
Power transformers and other devices which cause
magneticfields can induce hum in audio cables. This can
be best combated by using balanced lines where inputs
and outputs permit. Balanced lines use two conductors
plus a shield (ground) to send a positive and negative
version of the audio signal down the line. These are in
close proximity and therefore pick up the same hum or
interference. At the input, the inverted (-) signal is flipped
back and mixed with the original, canceling any hum or
interference.
Since all the inputs of the Numark amps are balanced,
accepting signals from a balanced output is no problem.
Should the output be unbalanced, the cable should be
wiredasfollows to ensure the best possible performance.
Thisapplies to XLR, 1/4” and barrier strip inputs alike:
+
-
GND
GND +
Where is a variable resistor, adjustable between 0 and 600 ohms.
amplifier inputs unbalanced output
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