Yamaha P4500 User Manual

POWER AMPLIFIER

Owner's Manual
Mode d'emploi
Bedienungsanleitung
Manual de instrucciónes

TEMP
PROTECTION
POWER

ON OFF

EEEngine

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CLIP

SIGNAL

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40

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–dB∞ 0 ∞ 0

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AB

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M

Introduction

Thank you for purchasing a Yamaha P4500/3200/1600 series power amplifier.
This series of audio amps was developed from Yamaha's wealth of experience in building PA

equipment and its tradition of careful attention to every detail of circuit design. These amps
feature high power and superb quality together with superior reliability and stability, guarantee­ing the highest possible audio performance.

Main features of the P4500/P3200/P1600 series

• Three types of input jack (balanced XLR type connectors, balanced phone jacks, and barrier
strip), and five-way binding post output jacks are provided, allowing use in a wide variety
of situations including installed applications.

• Three operating modes are provided: STEREO mode in which CHANNEL A and B operate
independently, PARALLEL mode in which a mono source is output by two amp systems, and
BRIDGE mode in which the unit operates as a single high-power amplifier.

• A SIGNAL indicator and CLIP indicator is provided for each channel.

• The PROTECTION indicator shows the status of protective circuitry such as power-on/off
protection, output muting, and the DC detection circuit. The TEMP indicator warns of heat
sink overheating.

• Variable-speed low-noise fan(s) ensures high reliability even under demanding conditions.

This owner's manual covers the three models P4500, P3200 and P1600. In order to take full
advantage of your power amp and enjoy long and trouble-free operation, please read this owner's
manual carefully before use.

English

IMPORTANT NOTICE FOR

THE UNITED KINGDOM

Connecting the Plug and Cord

WARNING: THIS APPARATUS MUST BE EARTHED
IMPORTANT: The wires in this mains lead are coloured in accordance with

the following code:
GREEN-AND-YELLOW : EARTH
BLUE : NEUTRAL
BROWN : LIVE
As the colours of the wires in the mains lead of this apparatus may not

correspond with the coloured markings identifying the terminals in your
plug, proceed as follows:

The wire which is coloured GREEN and YELLOW must be connected to
the terminal in the plug which is marked by the letter E or by the safety earth
symbol or coloured GREEN and YELLOW.

The wire which is coloured BLUE must be connected to the terminal which
is marked with the letter N or coloured BLACK.

The wire which is coloured BROWN must be connected to the terminal
which is marked with the letter L or coloured RED.

* This applies only to products distributed by YAMAHA KEMBLE

MUSIC (U.K.) LTD.

Precautions

1. Avoid excessive heat, humidity, dust and vibration.

Keep the unit away from locations where it is likely to be
exposed to high temperatures or humidity — such as
near radiators, stoves, etc. Also avoid locations which
are subject to excessive dust accumulation or vibration
which could cause mechanical damage.

2. Ventilation

Allow a distance of 10 cm between the unit and the wall
so that heat generated from the unit will be released
effectively. Also, allow enough space between the unit
and other devices. If you mount the unit in an audio rack,
keep a space of 10 cm on the top panel, and a space of
1 cm to the side panel. Remove the rear panel of the rack
or open a vent hole. If heat release is inadequate, the unit
will retain heat inside the unit, which may cause a fire.

3. Avoid physical shocks.

Strong physical shocks to the unit can cause damage.
Handle it with care.

4. Do not open the case or attempt repairs or modifica­tions yourself.

This product contains no user-serviceable parts. Refer
all maintenance to qualified Yamaha service personnel.
Opening the case and/or tampering with the internal
circuitry will void the warranty.

5. Make sure power is off before making or removing
connections.

Always turn the power OFF prior to connecting or
disconnecting cables. This is important to prevent dam­age to the unit itself as well as other connected equip­ment.

6. Handle cables carefully.

Always plug and unplug cables — including the AC cord
— by gripping the connector, not the cord.

7. Clean with a soft dry cloth.

Never use solvents such as benzine or thinner to clean
the unit. Wipe clean with a soft, dry cloth.

8. Always use the correct power supply.

Make sure that the power supply voltage specified on the
rear panel matches your local AC mains supply. Also
make sure that the AC mains supply can deliver more
than enough current to handle all equipment used in your
system.

Contents

Controls and Functions ............................................................. 2

Front Panel........................................................................... 2

Rear Panel ........................................................................... 3

Modes: STEREO/P ARALLEL/BRIDGE................................ 4

SPEAKER IMPEDANCE...................................................... 4

Caution for Speaker Connection ............................................... 5

Rack Mounting .......................................................................... 6

Mounting in an EIA standard rack ....................................... 6

Mounting four or fewer amps in an open-backed rack......... 6

Mounting five or more amps, or when (even with four or

fewer units) the back of the rack cannot be left open.......... 6

Portable Rack Mounting ...................................................... 7

Positioning the Housed Amplifier......................................... 7

Specifications ............................................................................ 8

General Specifications......................................................... 8

Block Diagram...................................................................... 9

Dimensions .......................................................................... 9

Performance Graphs.......................................................... 10

Troubleshooting ...................................................................... 10

Controls and Functions

■ Front Panel

23

TEMP
PROTECTION
POWER

ON OFF

1 POWER switch and indicator

This is the main POWER switch. Press to power ON the
amplifier. Press again to power OFF. The POWER
indicator lights up when the amplifier is powered ON.

2 TEMP indicator

When the temperature of the heat sink exceeds 85
degrees Celsius, this indicator will light red.

3 PROTECTION indicator

This red LED indicator lights up for approximately 3
seconds when the amplifier is powered ON, indicating
that the soft-start protection system is working. No
sound is output during soft-start up. If one of the protec­tion systems is activated during normal use, this indica­tor lights up and no sound is output. The speaker system
is actually disconnected from the amplifier outputs when
this indicator lights up. The protection systems are
activated when overheating occurs or a DC voltage is
present at the amplifier outputs. If the problem is cor­rected, the protection systems deactivate automatically,
this indicator goes out, and normal amplifier operation is
resumed.

EEEngine

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CLIP

AB

SIGNAL

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30

40

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–dB∞ 0 ∞ 0

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4 CLIP indicators

These red LED indicators light up when the respective
channel’s output signal distortion exceeds 1% (i.e. clip­ping). Output signal clipping is usually due to excessive
input signal levels.

5 SIGNAL indicators

These green LED indicators light up when the respective
channel’s output signal exceeds 2 Vrms. This is equiva­lent to 1/2 watt into 8Ω, 1 W into 4Ω.

6 Volume controls

These volume controls allow you to adjust the volume
level in 31 steps in the range between –∞ dB and 0 dB.
To fix the volume setting by protecting the controls,
install the included security cover over the controls and
tighten the screws in the holes as shown below.

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–dB∞ 0 ∞ 0

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■ Rear Panel

SPEAKERS

CHANNEL B CHANNEL A

STEREO

BRIDGE

SPEAKERS

CHANNEL B CHANNEL A

STEREO

BRIDGE

3214

INPUT SPEAKERS

CHANNEL B CHANNEL A

GG

1 INPUT terminals (CHANNEL A, B)

Three types of balanced terminals for channels A and B
are provided.
Channel A input terminal is used in Bridge and Parallel
mode.

• XLR-3-31 type connector

They are wired pin 1–ground, pin 2–hot (+), and pin 3 cold
(-).

GroundHot

1

2

3

Cold

(BRIDGE)
(PARALLEL)

BRIDGE

STEREO PARALLEL

CHANNEL B CHANNEL A

STEREO
BRIDGE

MAX. OUTPUT 450W/4Ω (STEREO)
MAX. OUTPUT 900W/8Ω (BRIDGE)

(STEREO)
4-8Ω/SP
(BRIDGE)
8-16Ω/SP

3 SPEAKERS terminals

For polarity in each mode, refer to the following dia­gram.

• STEREO, PARALLEL mode

• BRIDGE mode

• Phone jack

They are wired tip–hot (+), ring–cold (-), and sleeve–
ground.

Ring

Sleeve Tip

• Barrier strip

Hot (+), Cold (-) and Ground (G).

2 STEREO/BRIDGE/PARALLEL switch

This slide switch is used to set the amplifier operating
mode: STEREO, BRIDGE or PARALLEL.
For details on the functionality of each mode, refer to
“Modes” on page 4.

In BRIDGE mode, the (-) jacks of CHANNELS A and
B are not used.
The minimum impedance for the connected speaker
system is specified in “Speaker Impedance” on page 4.

4 GND terminals

This is the grounding screw terminal. If hum or noise
occurs, ground (earth) the unit via this jack, or try
connecting it to the chassis of the mixer or preamp, etc.

3

■ Modes: STEREO/PARALLEL/BRIDGE

y

y

y

STEREO mode

In this mode, channels A and B operate independently
(as a conventional stereo amp).
The CHANNEL A input signal will be output from the
CHANNEL A output jacks, and the CHANNEL B input
signal will be output from the CHANNEL B output
jacks.

PARALLEL mode

In this mode, the CHANNEL A input signal will be
output from the output jacks of both channels A and B.
The CHANNEL B input jack is not used. The (channel)

A

and B volumes can be adjusted independently.

■ SPEAKER IMPEDANCE

In STEREO and PARALLEL modes, the minimum load
(=speaker) impedance is 4Ω. In BRIDGE mode it is 8Ω.
Make sure that the impedance does not fall below this
specified impedance.

STEREO mode connections

BRIDGE mode

In this mode, the CHANNEL A input signal will be
output from the BRIDGE output jacks. In this case, use

the front panel (channel) A volume control to adjust the
volume.

BRIDGE mode connections

SPEAKERS

CHANNEL B CHANNEL A

Set to STEREO

BRIDGE

STEREO PARALLEL

MAX. OUTPUT 450W/4Ω (STEREO)
MAX. OUTPUT 900W/8Ω (BRIDGE)

–+

4Ω min. 4Ω min.

Speaker S

PARALLEL mode connections

SPEAKERS

CHANNEL B CHANNEL A

Set to PARALLEL

BRIDGE

STEREO PARALLEL

MAX. OUTPUT 450W/4Ω (STEREO)
MAX. OUTPUT 900W/8Ω (BRIDGE)

– +

STEREO
BRIDGE

STEREO
BRIDGE

stem

–+

– +

Set to BRIDGE

BRIDGE

STEREO PARALLEL

SPEAKERS

CHANNEL B CHANNEL A

STEREO
BRIDGE

MAX. OUTPUT 450W/4Ω (STEREO)
MAX. OUTPUT 900W/8Ω (BRIDGE)

– +

8Ω min.

Speaker S

stem

4Ω min. 4Ω min.

Speaker S

stem

4

Caution for Speaker Connection

1. Turn off the POWER switch.

2. Remove the cover attachment screw(s) and remove the
protective cover from the speaker terminals.

Screw

3. After removing approx. 10 mm of insulation from the
ends of the speaker cables, pass the bare ends of the
speaker wires through the holes in the corresponding
speaker terminals and tighten the terminals to securely
clamp the wires.
Refer to page 3 for speaker porality.

10mm

• Speaker fuse

The output capacity of your amplifier is very high: 460
W+460 W (8Ω) in stereo and 1240 W (8Ω) in monaural
on the P4500; 340 W+340 W (8Ω) in stereo and 880 W
(8Ω) in monaural on the P3200; 160 W+160 W (8Ω) in
stereo and 400 W (8Ω) in monaural on the P1600. Be
sure to use a speaker system that has sufficient input
capacity.
If the input capacity of your speaker system is lower than
the rated output of the power amplifier, you can protect
your speakers by connecting a fuse serially between the
speaker and amplifier as shown below.

Power amplifier

_

+ _

Fuse

Speaker system

+

Use the following formula to determine the fuse capacity
according to the speaker’s input capacity.

2

Po = I R → I = √Po/R

At this time make sure that the bare ends of the speaker
cables do not extend from the terminals in such a way
that they touch the chassis.

Wireshouldnot
touchthechassis.

4. Reattach the protective cover over the speaker termi­nals.

P0 [W] : Speaker’s continuous input capacity (noise or

RMS)

R [Ω] : Speaker’s nominal impedance
I [A] : Required fuse capacity

ex.) Speaker’s continuous input capacity : 100 W

Speaker’s impedance : 8Ω

I = √100/8

In this example, the required fuse capacity is calculated
as 3.5 [A].

• Speaker cable

If you use a long speaker cable, use as thick a cable as
possible to prevent deterioration of the damping factor
or power loss inside the cable.

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