Krell Showcase 5, Showcase 6, Showcase 7 Owners manual

Instructions for Use

Owner’s Reference

THE LEADER IN AUDIO ENGINEERING

Showcase 7
Showcase 6
Showcase 5

Multichannel Amplifier

© 2002 by Krell Industries, Inc. All rights reserved P/N 306039

This product is manufactured in the United States of America. Krell®is a registered trademark of Krell
Industries, Inc., and is restricted for use by Krell Industries, Inc., its subsidiaries, and authorized agents. Krell
Current Mode™ is a trademark of Krell Industries, Inc. All other trademarks and tradenames are registered
to their respective companies.

Showcase 7
Showcase 6
Showcase 5

Multichannel Amplifier

Instructions for Use

v 02.1

Krell Industries, Inc.
45 Connair Road
Orange, CT 06477-3650 USA

TEL [phone]
FAX [phone]
E-MAIL [e-mail]
WEBSITE http://www.krellonline.com

This product complies with the EMC directive (89/336/EEC) and the low-voltage
directive (73/23/EEC).

The amplifier must be placed on a firm, level surface where it is not exposed to
dripping or splashing.

The ventilation grids on the top, bottom, and sides of the amplifier must be unob­structed at all times during operation. Do not place flammable material above or
beneath the amplifier.

Contact your authorized Krell dealer, distributor, or Krell before using any devices
designed to alter or stabilize the AC power for the Showcase Amplifier.

Before connecting the Showcase Amplifier, make sure the amplifier is turned off
and any output device (such as a preamplifier) is in mute or stand-by mode. Make
sure all cable terminations are of the highest quality and free from frayed ends,
short circuits, or cold solder joints.

Use only one input to each amplifier channel at a time.

If the red LED flashes when the amplifier is in the stand-by mode, unplug the
amplifier to reset the protection circuit. Check the loudspeakers and loudspeaker
cables for potential short circuits before reconnecting the amplifier to your system.

THERE ARE NO USER SERVICEABLE PARTS INSIDE THE PREAMPLIFIER

Please contact your authorized Krell dealer, distributor, or Krell if you have any ques­tions not addressed in this reference manual.

CONTACT
INFORMATION

WARNINGS

Contents

Krell Showcase Amplifier iii

INTRODUCTION 1

DEFINITION OF TERMS 2

UNPACKING 3

PLACEMENT 4

AC Power Guidelines 4

FRONT PANEL DESCRIPTION 6

BACK PANEL DESCRIPTION 8

CONNECTING THE SHOWCASE AMPLIFIER
TO YOUR SYSTEM 10

Input and Output Connections 10

AMPLIFIER OPERATION 12

On/Off and Operation 12

TROUBLESHOOTING SYSTEM NOISE 13

QUESTIONS AND ANSWERS 14

WARRANTY 15

RETURN AUTHORIZATION PROCEDURE 16

SPECIFICATIONS 17

Page

iv Krell Showcase Amplifier

FIGURE 1 The Showcase Amplifier Front Panel 5

FIGURE 2 The Showcase Amplifier Back Panel 7

Illustrations

Page

Krell Showcase Amplifier 1

Thank you for your purchase of a Krell Showcase Amplifier.

The Showcase Amplifier is a flexible design that delivers five, six,
or seven channels of amplification. All three configurations include
input and output connections for all seven channels. The amplifiers
differ only by how many channels are housed within the amplifier.
A Showcase 5 includes five amplifier channels, a Showcase 6
includes six amplifier channels, and a Showcase 7 includes seven
amplifier channels. The Showcase 5 and Showcase 6 may be
upgraded with additional channels, up to seven. The Showcase
Amplifier has balanced and single-ended inputs for compatibility
with other components. The amplifiers can be operated using the
12 VDC power on/off (12 V trigger) signals from other components.
The Showcase Amplifier is versatile, fitting a variety of installations
including rack-mounted and inside cabinetry.

Please contact your Krell-authorized dealer or distributor for infor­mation on upgrading your amplifier to six or seven channels.

This reference manual contains important information on place­ment, installation, and operation of the Showcase Amplifier. Please
read this information carefully. A thorough understanding of these
details helps ensure satisfactory operation and long life for your
Showcase Amplifier and related system components.

Introduction

2 Krell Showcase Amplifier

Following are the definitions of key terms used in your owner’s ref­erence manual.

Balanced

A symmetrical input or output circuit that has equal impedance from
both input terminals to a common ground reference point. The
industry standard for professional and sound recording installations,
balanced connections have 6 dB more gain than single-ended con­nections and allow the use of long interconnect cables. Balanced
connections are less susceptible than single-ended connections to
induced noise from the system or the environment.

Single-ended

A two-wire input or output circuit. Use care when using single­ended connections as the ground connection is made last and bro­ken first. Turn the system off prior to making or breaking single­ended connections. Single-ended connections are not recommend­ed for connections requiring long cable runs.

Off

When the AC power cord is not plugged into the wall, the red
stand-by LED is not illuminated and the component is off.

Stand-by Mode

When the AC power cord is plugged into the wall, the red stand-by
LED illuminates, indicating that the component is in the stand-by
mode. This low power consumption status keeps the audio and cir­cuits at idle. Krell recommends leaving the component in the stand­by mode when it is not playing music.

Operational Mode

From the stand-by mode, when the power button on the front panel
is pressed and the blue power LED illuminates, the component is in
the operational mode and ready to play music.

Krell Current Mode

A proprietary Krell circuit topology in which the audio gain stages of
a component operate in the current rather than the voltage domain.
This unique technology provides the component with exceptional
speed and a wide bandwidth.

Definition of Terms

INPUT AND OUTPUT
CONNECTIONS

OPERATION

TECHNOLOGY

Unpacking

Krell Showcase Amplifier 3

1. Open the shipping box, and remove the top layer of foam. The
following items are visible:

1 Showcase Amplifier

1 Accessory Kit containing:

1 AC power cord
1 12 VDC output (12 V trigger) cable
1 spare AC mains fuse
1 10 A slow-blow fuse for 100–120 VAC
1 5 A slow-blow fuse for 220– 240 VAC

1 packet containing the owner’s reference manual and the

warranty registration card.

Two people are needed to remove the amplifier from the shipping
box.

2. Grasp the underside of the amplifier and lift it straight out of the
shipping box.

3. Place the amplifier in a safe location and remove the protective
plastic wrapping.

If any of these items are not included in the shipping box, please contact
your authorized Krell dealer, distributor, or Krell for assistance.

Save all packing materials. If you ship your amplifier in the future, repack
the unit in its original packaging to prevent transit damage. See Return

Authorization Procedure, on page 16, for more information.

IMPORTANT

Notes