Tascam Dual Power Amplifier PA-30 Owners Manual

							»
PA-30
Dual Power Amplifier
OWNER’S MANUAL
9A09572800 
						

							The TASCAM PA-30 is a high-performance
professional audio power amplifier for nearfield studio
monitoring and low-level sound reinforcement. In
stereo mode, the PA-30 delivers 30 watts per channel
continuously into an 8 ohm load - with no more than
0.05% total harmonic distortion. For applications
requiring higher output power, the unit may be
operated in BTL (Balanced Transformerless) mode -
also known as bridged operation - and will deliver a
full 60 watts continuously into 8 ohms (see the BTL
Operation section of this manual on page 9). In either
mode, it exhibits a flat frequency response
characteristic from 20 Hz to 20 kllz (+0, –1dB), with
very low residual hum and noise.
For maximum flexibility, the PA-30 is equipped with
both XLR-type balanced and RCA-type unbalanced
input connectors.  These accommodate nominal input
signal operating levels of +4 dBm and –10 dBV,
respectively essentially eliminating the necessity for
external compensating pads or gain stages. A single,
continuously variable INPUT LEVEL control
attenuates input signals so the units sensitivity can be
calibrated to the gain structure of the source equipment.
The PA-30 is designed and built to provide years of
trouble-free service with little or no maintenance. Its
well built power transformer easily handles continuous
full-power operation, and all power semiconductor
circuits are mounted on a large convection-cooled
heatsink.Multiple resettable electronic protection circuits guard
against destructive turn-on transients, output overload,
DC offsets and output shorts.
While the PA-30 is almost indestructible, it has been
engineered to be easy to service. Like all TASCAM
professional products, it is backed by a worldwide
network of TASCAM dealers and TEAC authorized
TASCAM service centers.
Connection and operation of the PA-30 is simple and
straightforward. This manual presents a detailed
description of the units features, along with basic
connection instructions and specifications. Please take
a few moments to study it before connecting and
operating your PA-30 Power Amplifier.
TABLE OF CONTENTS
Introduction................................................................. 2
Important Safety Instructions ..................................... 3
Summary of Operating Precautions ............................ 4
Features ....................................................................... 5
Connection & Installation ........................................... 7
BTL Operation ............................................................ 9
Specifications ............................................................ 10
 Introduction
2  TASCAM PA-30
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.
The exclamation point within an equilateral triangle is intended to alert the user to the pres-
ence of important operating and maintenance (servicing) instructions in the literature
accompanying  the  appliance. 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 to persons.
This appliance has a serial number
located on the rear panel. Please record
the model number and serial number
and retain them for your records.
Model number
Serial number
Ü
ÿ
Ÿ
WARNING: TO PREVENT FIRE OR SHOCK
HAZARD, DO NOT EXPOSE THIS 
APPLIANCE TO RAIN OR MOISTURE. 
						

							1) Read these instructions.
2) Keep these instructions.
3) Heed all warnings.
4) Follow all instructions.
5) Do not use this apparatus near water.
6) Clean only with dry cloth.
7) Do not block any ventilation openings. Install in
accordance with the manufacturers instructions.
8) Do not install near any heat sources such as
radiators, heat registers, stoves, or other apparatus
(including amplifiers) that produce heat.
9) Do not defeat the safety purpose of the polarized or
grounding-type plug. A polarized plug has two blades
with one wider than the other. A grounding type plug
has two blades and a third grounding prong. The wide
blade or the third prong are provided for your safety. If
the provided plug does not fit into your outlet, consult
an electrician for replacement of the obsolete outlet.
10)Protect the power cord from being walked on or
pinched particularly at plugs, convenience receptacles,
and the point where they exit from the apparatus.
11) Only use attachments/accessories specified by the
manufacturer.
12) Use only with the cart, stand, tripod, bracket, or
table specified by the manufacturer, or sold with the
apparatus. When a cart is used, use caution when
moving the cart/apparatus combination to avoid injury
from tip-over.
13) Unplug this apparatus during lightning storms or
when unused for long periods of time.
14) Refer all servicing to qualified service personnel.
Servicing is required when the apparatus has been
damaged in any way, such as power-supply cord or
plug is damaged, liquid has been spilled or objects have
fallen into the apparatus, the apparatus has been
exposed to rain or moisture, does not operate normally,
or has been dropped.• Do not expose this apparatus to drips or splashes.
• Do not place any objects filled with liquids, such as
vases, on the apparatus.
• Do not install this apparatus in a confined space such
as a book case or similar unit.
• The apparatus draws nominal non-operating power
from the AC outlet with its POWER switch in the off
position.
IMPORTANT SAFETY INSTRUCTIONS
TASCAM PA-30  3 
						

							•Do not use the PA-30 if the power cord appears
frayed or broken.
•Do not spill liquids into or on the PA-30 chassis. If
the chassis becomes wet, allow it to dry thoroughly
before reconnecting the unit.
•Allow sufficient space at the top, and bottom of the
PA-30 to permit a flow of cooling air. Keep the unit
away from radiators or others that produce heat.
•Never connect the PA-30 outputs to a battery, power
supply or other voltage source. Do not short the
output hot terminals together.
•The  minimum  allowable  load  impedance  on  each
PA-30 output is 8 ohms in stereo mode or BTL mode.
Connecting loads of lower impedance will result in
current limiting and/or activation of the protection
circuits.
•Before operating the PA-30, be certain that the
MODE switch is set in accordance with the desired
operational mode and output connection
configuration (see the BTL Operation section of this
manual, page 9).
•Any unauthorized internal modification to the PA-30
will invalidate the warranty, and may result in
hazardous conditions. Refer all servicing to a TEAC
authorized TASCAM service center.
•Connect the PA-30 only to properly wired AC outlets.
Make certain that the voltage is correct for the
version of the unit that you are using (110 to 120
volts at 60 Hz for domestic USA).
AC Power Connection
The PA-30 requires a reliable source of single-phase
power at 110 to 120 volts AC, 60 Hz (domestic US
version). It has a two-prong, ungrounded AC cord, and
may be connected to either two-prong or three-prong
outlets.
If you have any doubt about the wiring of the outlet that
you wish to use, it is wise to test it before making
connections. Simple plug-in testers are available from a
variety of electronics and hardware stores.If an outlet appears to require repairs, consult a
qualified electrician - and 
dont use it. An  improperly-
wired outlet may present a serious shock hazard.
For reference, Figure 1 shows the characteristics of a
properly wired US standard three-prong wall outlet.
Figure 1. Standard wall Receptacle
Voltage Conversion
Be sure to unplug the power cord from the AC outlet
before repositioning the voltage converter switch.
1) Locate the voltage selector on the rear panel.
2) Using a flat-bladed screwdriver, set to the
appropriate 120 V or 230 V position according to
your area.
Figure 2. Voltage Selector
Neutral
EarthHot
0 ohms
0 Volts
0 Volts
120 VAC 120 VAC
120V
Summary of Operating Precautions
4  TASCAM PA-30 
						

							1. POWER Switch and Indicator
A two-position rocker-type switch controls power to
the unit. Depressing the upper surface of the switch
turns the amplifier on; depressing the lower surface
turns it off. The green LED Power indicator will light
whenever the unit is on and is connected to a properly
functioning source of power.
2. PROTECTION Indicator
The red LED Protection indicator remains off
whenever the PA-30 is turned on and is operating
normally.
If an overload, short circuit, DC offset or other problem
triggers the internal electronic protection circuitry, the
unit shuts down and the Protection indicator lights.
Once the PA-30 is turned off and the fault condition is
cleared, the Protection circuit will automatically reset,
and normal operation can be resumed (provided that
the fault has not damaged the unit).If the Protection indicator lights when the PA-30 is
first switched on, turn the Power switch OFF and
recheck all of your connections before resetting
power.
3. BTL Indicator
The orange LED BTL indicator will light whenever the
MODE switch (on rear panel) is in the BTL (MONO)
position.
4. INPUT LEVEL Control
A single rotary variable attenuator sets the input
sensitivity of the PA-30 Amplifier. The degree of
attenuation varies from zero loss (maximum
sensitivity) at the MAX position to infinite loss at the
MIN position.
5. PHONES Jack
This Tip/Ring/Sleeve 1/4 phone jack accommodates 8
ohms or higher impedance stereo headphones.
Features
TASCAM PA-30  5
Figure 3. PA-30 FRONT PANEL 
						

							6. INPUTS (A & B, XLR & RCA Type)
Two input connectors are provided for each channel:
one RCA (phono) jack and one XLR-type female
connector. Either connector may be used on a given
channel, but both connectors for a single channel
should not be used simultaneously.
Both inputs present a high impedance, and cause no
appreciable loading to source outputs. Input sensitivity
is –10 dBV (0.3 volt RMS) at the RCA inputs, and +1.3
dBu (0.9 volt RMS) at the XLR inputs, for rated output
(with Input Level control at maximum). Pin
assignments are as follows:
XLR-type
RCA-type
Pin I = common Shell= common
Pin 2= high(+) Tip = high(+)
Pin 3= Iow(–)
Virtually any line-level source may be connected to
these inputs. (Refer to the Connection and Installation
section for further details.)
7. MODE switch
A single two-position slide switch (on rear panel)
selects either monophonic BTL (Balanced
Transformerless, also known as bridged, with switch
set to BTL) or stereo operation (with switch set to
STEREO).
If the MODE switch is not correctly set, damage to the
loudspeakers or to the PA-30 may result. For a
complete explanation of use of the MODE switch,
consult the section on BTL Operation on page 9 of
this manual.
8. SPEAKERS (A & B)
A pair of color-coded locking terminals is provided for
output connections to each channel of the PA-30. They
will accommodate stripped bare wire, or tinned wine
ends. The minimum allowable load impedance for each
output is 8 ohms.
The actual output connection configuration will vary
depending upon the mode of operation selected and
the number and type of loudspeakers used. Please
refer to the sections on BTL Operation and Output
Connections before making connections to the PA-30
outputs.
9. Mains Power Cord
The inlet for AC power to the PA-30 is a two-prong
ungrounded plug (rear panel mounted). The PA-30
requires 120/230 volts AC at 50/60 Hz. It draws 8 watts
at idle, and 130 watts at full rated output.
Features
6  TASCAM PA-30
Figure 4. PA-30 REAR PANEL
120V 
						

							Input Connections
Before making connections to the PA-30 signal inputs,
find the nominal output level of your signal source (this
information is usually given in the Specifications
section of the instruction manual). Equipment
operating at –10 dBV should be connected to the RCA
(phono) inputs, while +4 dBm equipment will operate
best if connected to the XLR-type inputs. (Low-level
signal such as an electric guitar or phonograph
cartridge will require an external preamplifier.)Components that operate at –10 dBV normally feature
either RCA or 1/4-inch phone output connectors,
presenting an unbalanced (two-connection) drive.
Standard connecting cables and adapters may be used
with such equipment. If you are making your own
cables, refer to Figure 5 for wiring details.
Connection and Installation
TASCAM PA-30  7
Professional +4 dBm components, on the other hand,
may feature either 1/4-inch phone or XLR-type output
connectors, presenting either an unbalanced or a
balanced drive. In some cases, standard microphone
cables may be used for such equipment; in others,
special cables or adapters may be required.
Figure 6 shows the recommended wiring configu-
rations for a few standard +4 dBm output types. Referto this figure when determining the types of cables and
adapters to use in connecting to the PA-30 XLR inputs.
Take care to observe the polarity conventions indicated;
input polarity reversals may cause acoustical phase
cancellation, resulting in unnatural sound.
Figure 5. Connections to the PA-30 –10 dBV Input
Figure 6. Connections to the PA-30 +4 dBm Input
From Source EquipmentTo PA-30 RCA Input
From Source EquipmentTo PA-30 XLR Input
Note: if source is pin 3 hot
  reverse pins 2 & 3
Note: if source is pin 3 hot
   reverse pins 2 & 3 UnbalancedConnect to pin 1
if required by source output
Balanced(Two-Conductor Shielded Cable)
(Single-Conductor Shielded Cable) 
						

							Output Connections
Each channel of the PA-30 will drive a minimum load
impedance of 8 ohms. Connecting a load of lower
impedance will result in current limiting and may
trigger the Protection circuits to shut down the
amplifier.
Figure 7 shows a normal stereo-mode connection of
two individual speakers to the PA-30 outputs. When
making loudspeaker connections, always be sure to
maintain correct polarity; if you wire the speakers out
of phase with one another, you will get acoustical phase
cancellations.
There are two basic methods for connecting multiple
speakers to a single amplifier output: series connection
and parallel connection. Loudspeakers connected in
series present a higher net impedance than any single
unit alone. Parallel connection, by contrast, lowers the
net load impedance. Sometimes, the two methods arecombined to obtain an optimum load impedance.
Figure 8 shows what happens to the net load impedance
when multiple loudspeakers are connected in various
ways. (In all cases, it is assumed that all speakers in a
given system have the same impedance.)
Generally, only parallel connection is used in
professional audio, for two fundamental reasons. First,
if one of the speakers in a parallel system fails, the
others will still function. (Remember those old
Christmas lights that all went out the minute one bulb
failed? They were connected in series.) Second, parallel
connection results in a lower net impedance. The closer
the load impedance gets to the allowable minimum for
the amplifier, the more efficiently is the amplifiers
power capability used, since the lower load impedance
draws more current from the output stage.
8  TASCAM PA-30
Connection and Installation
Figure 7. Typical Stereo Output Connection
Figure 8. Connecting Multiple Loudspeakers
Each Unit
4 OHMS
8 OHMS
16 OHMSTwo In Series
8 OHMS
16 OHMS
32 OHMSThree In Series
12 OHMS
24 OHMS
48 OHMSFour In Series
16 OHMS
32 OHMS
64 OHMS
Each Unit
4 OHMS
8 OHMS
16 OHMS
Note: Impedances shown in brackets are
too low for the amplifier. Do not use three
loudspeaker configurations.
Two In Parallel
(2 OHMS)
(4 OHMS)
8 OHMSThree In Parallel
(1.33 OHMS)
(2.66 OHMS)
(5.33 OHMS)Four In Parallel
(1 OHM)
(2 OHMS)
(4 OHMS)Four In Series/Parallel
(4 OHMS)
8 OHMS
16 OHMS
120V 
						

							The PA-30 rear panel includes a switch that selects
either normal stereo mode or a special mode termed
BTL (Balanced Transformerless).  The setting of this
switch determines the maximum power available to the
load from the PA-30, and also decisively affects how
the load is connected to the amplifier.  This section
explains the BTL mode, and describes how to use it.
Theory of Operation
BTL mode (also called bridged mode) uses both
channels of the PA-30 to form a single monophonic
amplifier with significantly higher power capability. If
your loudspeakers can handle the increased power,
BTL mode will give you more headroom - resulting in
undistorted reproduction of program peaks and
significantly greater punch from your system.
When the MODE switch is in the BTL (MONO)
position, only the Channel A input is active; the
Channel B input is disabled, and signals present at
either of the Channel B input connectors are ignored by
the amplifier. The signal at the Channel A input is
amplified and sent to both outputs of the PA-30, 
but the
polarly of Channel B is reversed with respect to
Channel A
. In other words, the two channels are
intentionally out of phase.
The single load (remember, BTL is a monophonic, or
single-channel, mode) is wired across the two channel
output hot (red) terminals, and the black output
terminals are left unconnected. The minimum
allowable load impedance is 8 ohms (not 4 ohms, as is
the case in stereo mode), and the available power to the
load is 50 watts continuous (at 8 ohms).
BTL mode is electrically identical to push-pull
transmission at line level (the signal level is simply
much higher): the two channel outputs deliver the same
absolute signal voltage, but with opposite polarities.
So, when the Channel A output is at +10 volts, for
example, the Channel B output is at –10 volts. The
difference between the two (which is the total voltage
across the load) is then 20 volts.The voltage across the load is thus effectively doubled
– which doubles the power.
Notice there is a crucial difference between BTL mode
and what is normally termed mono in the HiFi world.
When we select mono on a HiFi preamp or integrated
amplifier, what we intend - and what we get - is the
same signal from both speakers 
with the same polarity.
It is very important to understand the distinction
between this and BTL mode, because if two speakers
are connected to the PA-30 in a normal stereo
configuration and the MODE switch is set to BTL, the
system still works but the two speakers are out of
phase.  This will cause acoustical cancellations at low
frequencies, resulting in poor sound quality. In rare
cases, it can even cause a woofer to blow out!
Connections
Before changing the position of the MODE switch or
making any input and output connections, turn OFF the
PA-30. To select BTL operation, move the MODE
switch to the BTL (MONO) position.
Figure 9 illustrates the connections for BTL mode. The
input signal is connected to the Channel A input, using
either the –10 dBV (RCA) or the +4 dBm (XLR)
connector. The Channel B input is left unconnected.
The load is connected across the two output hot (red)
terminals, and the black terminals are left unconnected.
Be sure to observe correct output polarity: Channel A is
positive, and Channel B is negative. Note that the
minimum permissible load impedanoe in BTL mode is
8 ohms.
Connecting loads with a lower impedance will result in
current limiting, and may trigger the Protection circuits
to shut down the amplifier.
TASCAM PA-30  9
BTL operation
Figure 9. BTL Mode Connection
120V
NO CONNECTION TO BLACK TERMINALS 
						

							Output power at 8 ohms, (1 kHz):30 Watts minimum RMS per channel in stereo
mode, both channels driven. (0.05% THD)
60 Watts minimum RMS in BTL (monophonic)
mode. (0.08% THD)
T otal Harmonic Distortion (1 kHz):
0.05% (30 Watts 8 ohms, STEREO)
0.08% (60 Watts 8 ohm, BTL)
Intermodulation Distortion: Less than 0.2%, 70Hz: 7kHz (4:1)
Frequency Response: 20 Hz to 20 kHz, +0, 1 dB at rated power output.
Damping Factor: 80 minimum, 8 ohm load. 20 Hz to 20 kHz.
Input Impedance and SensItivity: –10dBV (0.3 volt RMS) for rated output, 15 kohm
unbalanced at RCA input.
+1.3 dBu (0.9 volts RMS) for rated output, 40
kohm balanced at XLR input.
Hum and Noise: 85 dB below rated output.
Minimum Load Impedance: 8 ohms per channel, stereo mode.
8 ohms, BTL mode. Protection Circuits:
DC balance voltage protector; electronic output
power overload protector
Semiconductor Complement: 9 transistors, 8 diodes, 2 integrated circuits,
3 LEDs.
Power Requimments: 120/230 volts, 50/60 Hz, AC switchable; 
8 Watts at idle, 130 Watts at rated output.
W eight:
4.5 kg net; 5.5 kg in shipping carton.
Physical Dimensions: 2.1 (54 mm) high, 19 (482 mm) wide, 10.9 (276
mm) deep.
NOTES:
Specifications subject to change without notice.
0 dBV is referenced to 1 volt RMS.
0 dBu is referenced to 0.775 volt RMS.
10  T ASCAM PA-30
Specifications