Crown PIPISO Owners manual

P.I.P.-ISO

ISO

Programmable
Input Processor (P.I.P.)

E106377

®

Applies only to North

American units.

CH-2 INPUT

+–

—WARNING—

THIS P.I.P. PROVIDES FULL ISOLATION
FOR ISO-MODIFIED AMPLIFIERS ONLY!

DO NOT CONNECT THE OUTPUT GROUND

LUG TO THE INPUT COMMON OR CHASSIS

GROUND. REFER TO P.I.P.–ISO OWNER’S

MANUAL FOR FURTHER INFORMATION.

CH-1 INPUT

+–

© 1997 by Crown International, Inc., P.O. Box 1000,
Elkhart, Indiana 46515-1000 U.S.A. Telephone: 219-294-

8000. Crown
Professional Audio Division of Crown International, Inc.
Trademark Notice:

Macro-Tech

®

and

P.I.P.

modules are produced by the

Com-Tech

P.I.P.

®

®

,

are registered trademarks of

Crown

®

,

Crown International, Inc. Other trademarks are the
property of their respective owners.

Amcron

125354-1

10/97

®

,

P.I.P.-ISO

Page 2

P.I.P.-ISO

CH-2 INPUT

ISO

+–

—WARNING—

THIS P.I.P. PROVIDES FULL ISOLATION
FOR ISO-MODIFIED AMPLIFIERS ONLY!

DO NOT CONNECT THE OUTPUT GROUND

LUG TO THE INPUT COMMON OR CHASSIS

GROUND. REFER TO P.I.P.–ISO OWNER’S

Programmable
Input Processor (P.I.P.)

MANUAL FOR FURTHER INFORMATION.

Fig. 1.1 P.I.P.-ISO

1 Welcome

Thank you for purchasing the
Crown

P.I.P.

quickly install in the rear panel of
many Crown amplifiers.
stands for “Programmable Input
Processor.” Their versatile fea­tures expand the capabilities of
your amplifier and enable you to
customize it for your particular
needs.

The
with ISO-MODIFIED
series amplifiers. If it is used with
an amplifier that is not iso-modified
it will not have full isolation. In such
a case, only the input (not the out­put) will be isolated from ground.
The
MOD KIT” so a
fier can be iso-modified. (These
kits are also available separately.)

The amplifier modification
should be performed only by a
qualified technician. Once an

amplifier has been iso-modified, it
should not be used with any other

P.I.P.

P.I.P.-ISO

®

modules are designed to

accessory.

P.I.P.

P.I.P.-ISO

is intended for use

Com-Tech

P.I.P.-ISO

modules except the

comes with a “ISO-

Com-Tech

ampli-

P.I.P.-

CH-1 INPUT

+–

ISO

. (It is also possible to iso-

modify a

Macro-Tech

plifier but the procedure is differ­ent. Contact the Crown Technical
Support Group for more informa­tion, if required, at 219/294-8200
or 800/342-6939.)

An iso-modified amplifier with a

P.I.P.-ISO

has completely isolated
outputs—the output voltage avail­able between the positive and
ground terminal is not referenced

®

to earth ground. Even if either out­put terminal is continuously
shorted to the earth ground (chas­sis), no damage will occur to the
amplifier or any equipment inter­connected to it.

The amplifier inputs are isolated
by means of input transformers.
The transformers are designed for
1 kVAC breakdown isolation and
have less than 25 pF of primary to
secondary capacitance yielding
excellent common mode rejection.

In addition to isolation, the

ISO

includes a switchable high-

pass filter to attenuate unwanted

®

series am-

P.I.P.-

Page 3

P.I.P.-ISO

subsonics or low frequencies and a
RFI (Radio Frequency Interference)
filter to attenuate ultrasonic frequen­cies.

You should find the following items
when you unpack:

P.I.P.-ISO module

Two 8-32 Phillips Machine Screws

Two Lock Washers

Two Quick-Disconnect Barrier Blocks

This Owner’s Manual

One ISO-MOD KIT containing:

One Isolation Network

One

P.I.P.

connector Keying Plug

One piece of self-stick Fish Paper

One ISO-MOD Warning Sticker

ISO-MOD Instruction Sheet

1.1 Features

❏ Fail-safe output isolation allows

either side of outputs to be
shorted to chassis ground with
no worries.

❏ EMI (Electro-Magnetic Inter-

ference) shielding provides
additional gain margin under
fault conditions.

❏ Balanced inputs with 1 kVAC

breakdown 1:1 isolation
transformers.

❏ Excellent common mode

rejection.

❏ RFI filter which attenuates

unwanted ultrasonic
frequencies that would
otherwise waste amplifier
power. The RFI filter is a
12 dB/octave (2nd order),
Bessel-tuned low-pass filter
with a 3 dB roll-off point at
33 kHz.

❏ Switchable subsonic/bass filter

with 50, 100 or 300 Hz roll-off
frequencies.

❏ Quick-connect barrier block

connectors provide greater
wiring flexibility and make
installation easier.

Page 4

ISO

Programmable
Input Processor (P.I.P.)

CH-2 INPUT

+–

—WARNING—

THIS P.I.P. PROVIDES FULL ISOLATION
FOR ISO-MODIFIED AMPLIFIERS ONLY!

DO NOT CONNECT THE OUTPUT GROUND

LUG TO THE INPUT COMMON OR CHASSIS

GROUND. REFER TO P.I.P.–ISO OWNER’S

MANUAL FOR FURTHER INFORMATION.

Fig. 2.1 Front View

CH-1 INPUT

+–

AA

P.I.P.-ISO

Fig. 2.2 Bottom View

CH 2 CH 1

BB

Fig. 2.3 Side View

2 Facilities

A. Balanced Input

With these special quick-connect
barrier-block connectors, it’s
quick and easy to attach each in­put cable with just three screws.
Once the cable is attached, the
connector can be quickly un­plugged and, if desired, moved to
a different amplifier.

FLAT

50 Hz

100 Hz

300 Hz

B

B. Subsonic/Bass Switch

A 4-position sliding switch is pro­vided for each channel to control
the subsonic/bass filter. This filter
is an 18 dB/octave (3rd order)
Butterworth high-pass filter which
can be selected to attenuate low
frequencies below 50 Hz, 100 Hz
or 300 Hz. It can also be switched
off (Flat). A label on the side of
each switch identifies the settings.

Page 5

P.I.P.-ISO

3 Installation

The

P.I.P.-ISO

lation with any
amplifier but it will only provide
output isolation with an amplifier
that has been ISO-MODIFIED.
Only a Crown-authorized service
technician should attempt to
modify an amplifier. Instructions
for iso-modifying
fiers are included in each ISO­MOD KIT.

Before installing this
you’ll want to adjust its subsonic/
bass filters to best serve your
needs.

provides input iso-

P.I.P.

-compatible

Com-Tech

P.I.P.

0

–6

dB

–12

–18

FLAT

ampli-

module,

50 Hz 100 Hz 300 Hz

This is easily accomplished with the
four-position sliding switch located
at either side of the

P.I.P.-ISO

(see
Figure 2.2 and 2.3). The switch on
the left controls the filter for Channel
2 and the switch on the right con­trols the filter for Channel 1. Each
switch is clearly labelled (Flat, 50
Hz, 100 Hz, 300 Hz). Figure 3.1
shows the low-frequency response
through the P.I.P.-ISO for each filter
position.

Note: The RFI filter is always on.

10 100 1 K

FREQUENCY (Hz)

Fig. 3.1 Subsonic/Bass Filter Settings

3.1 Installation Procedures

You may need a phillips screw­driver to remove the existing
module or panel from your amplifier.

CAUTION:CAUTION:

CAUTION: Before connecting this

CAUTION:CAUTION:
or any

P.I.P.

to your amplifier, it is
important to turn its level controls
down, turn it off and remove the AC
power. Don’t touch the circuitry.
Even though the amplifier is off,

Page 6

P.I.P.

there could still be enough energy
remaining to cause electric shock.

1. Turn down the level controls (full
counterclockwise), turn off the
amplifier and unplug it from the
AC power source.

2. Remove the existing

P.I.P.

module or panel (two screws).
For

PIP2

amplifiers, this may

P.I.P.-ISO

involve disconnecting the
from a

PIP2

input adapter (see

Figures 3.3 and 3.4). If a

P.I.P.

PIP2

input adapter is already present,
do not remove the ribbon cables
from the adapter. Otherwise you
will have to reconnect them in the
next step.

BACK PANEL

OF AMPLIFIER

P.I.P .

MODULE

Fig. 3.2 Installation into a

Standard P.I.P. Amplifier

FROM AMPLIFIER

Q43528-1

B
A

A

18 PIN (B)

B

20 PIN (A)

Fig. 3.3 PIP2 Input Adapter

Connection

BACK PANEL

OF PIP2

AMPLIFIER

PIP2 CONNECTOR

BOARD

P.I.P.

MODULE

Fig. 3.4 Installation into a

PIP2 Amplifier

Standard P.I.P. Amplifiers

3.
the edges of the

P.I.P.

card rails and firmly push

P.I.P.–ISO

: Align

in the

the unit in until it is seated against
the mounting bracket (see
Figure 3.2).

PIP2 Amplifiers:
PIP2

input adaptor. Crown part

(Requires a

number Q43528-1.) Connect

PIP2

the

input adapter to the two
input cables of the amplifier (see
Figure 3.3). Notice that the

PIP2

input adapter should be
positioned with the

P.I.P.

edge
connector on top and facing
away from the amplifier. The 20
pin cable (A) is connected first
then the 18 pin cable (B) is
connected. Both ribbon cables
should extend below the

PIP2

input adapter.
Next, insert the edge connector

of the

P.I.P.–ISO

into the

PIP2

input adapter (see Figure 3.4)
and insert the assembly into the

P.I.P.

opening in the back of the

amplifier.

4. Secure the

P.I.P.–ISO

with the
two screws and lock washers
provided. (The lock washers are
important because they bond

P.I.P.

the

to the chassis ground

of the amplifier.)

5. Connect input and output wiring.

6. Plug in the amplifier and turn it
on. Adjust its level controls to a
desired setting.

Do not tamper with the circuitry.
Circuit changes made by unautho­rized personnel, or unauthorized
circuit modifications are not al­lowed.

Page 7

P.I.P.-ISO

Remember: Crown is not liable for

any damage resulting from over­driving other components in your
sound system.

Figure 3.5 shows how to wire a bal­anced and unbalanced source or
daisy-chain output to the barrier
block connectors.

Important: If the amplifier is used in
either Bridged-Mono or Parallel-

BALANCED

SOURCE

– + – +

Mono mode, you
amplifier level control off (fully coun­terclockwise). The input and level
control of Ch. 2 are not defeated in
mono mode so any signal applied to
Ch. 2 will beat against the signal in
Ch. 1.

Refer to the amplifier

Manual

for more information about
Bridged-Mono or Parallel-Mono
modes of operation.

UNBALANCED

SOURCE

must turn the Ch. 2

Reference

Page 8

Fig. 3.5 Audio Wiring

P.I.P.-ISO

E106377

®

Applies only to

North American

units.

4 Specifications

Note: All specifications referenced
to a 0.775 V input signal.

Signal to Noise: Better than –90
dB (equivalent input noise) 20 Hz
to 20 kHz.

Common Mode Rejection: 85 dB
at 1 kHz; 78 dB at 10 kHz; 68 dB at
15 kHz.

Crosstalk: –85 dB at 1 kHz; –82
dB at 10 kHz; –80 dB at 15 kHz.

Harmonic Distortion: Less than

0.01% THD for 0 dBm input at 1
kHz with bass filter set to any posi­tion. Less than 0.5% THD for +10
dBm input above 50 Hz with bass

filter set to flat. Less than 0.5% THD
for +18 dBm input above 100 Hz
with bass filter set to flat.

Input Impedance: Nominally 10 K
ohm.

Maximum Source Impedance for
Proper Isolation: 600 ohms.

Maximum Input Level: +20 dB at

1 kHz.

Nominal Gain: Unity.
Frequency Response: ±1 dB

from 20 Hz to 15 kHz when sub­sonic/bass filters set flat. The sub­sonic/bass (high-pass) filters have
selectable –3 dB roll-off points of
50, 100 or 300 Hz (see Figure 3.6)
and can be switched off if desired.

A permanent RFI filter with a –3 dB
roll-off at 33 kHz also affects the
response.

Dimensions: 6 3/8 x 1 7/8 x 3 7/8 in
(16.2 x 4.8 x 9.8 cm).

Weight: 14 ounces (397 grams).

Page 9