Krell Industries 2250e, 3250e Quick Setup Manual

Krell Industries, LLC, 45 Connair Road,Orange, CT 06477-3650 USA
TEL [phone], FAX [phone], E-MAIL [e-mail]
WEB SITE www.krellonline.com

Connecting
the Amplifier

4 Krell Evolution 2250e and 3250e Series Amplifiers

Operating
the Amplifier

Notes

When powering up any system,
always turn amplifiers on last. When
powering down, always turn
amplifiers off first.

To avoid loudspeaker damage, be
sure to switch all sources with the
preamplifier level either muted or
fully attenuated. Do not change
inputs to the amplifier while the
amplifier is on.

Krell amplifiers have large reserves of
clean power and can safely drive
loudspeakers to higher sound
pressure levels than other amplifiers.
However, use care when setting high
playback levels and lower the
volume level at any sign of
loudspeaker distress.

AC POWER GUIDELINES

MODEL

SERIAL NUMBER

Operate each amplifier from a dedicated AC power line rated at a minimum of 20 amps.

Note

Do not operate the Evolution e Series amplifiers with any device designed to alter or stabilize AC power.

Follow these steps to connect the amplifier to your system:

1. Turn all power sources and components off before connecting inputs and outputs.

2.

Neatly organize the wiring between the amplifier and all system components. Separate AC wires
from audio cables to prevent hum or other unwanted noises from being introduced into the
system.

3. Connect the balanced operation, connect the interconnect cable(s) from your preamplifier to the
balanced XLR input(s) (6) on the amplifier back panel. For single-ended operation, connect the
interconnect cable(s) from your preamplifier to the single-ended input(s) (5) on the amplifier back
panel.

Notes

Krell recommends using balanced connections for superior sonic performance. The circuitry and connections
associated with balanced operation not only can minimize sonic loss but also are immune to induced noise,
especially for installations using long cables.

4. Connect the loudspeaker cables to the loudspeaker binding posts (3) on the amplifier back panel.
Loudspeaker binding posts for both stereo and monaural amplifiers only accept spade lugs.

5. Plug the AC power cord into the IEC power connector (9) on the back panel.

6. Plug the other end of the AC power cord into the wall socket.

Evolution e Series amplifiers are easy to operate:

1. Move the back panel power breaker switch (10) to the up position to place the amplifier in stand­by mode. The power status indicator (2) illuminates in gr

een. Green is the standby color and

indicates an ultra low power draw of 2 watts.

2. Press the power button (1) on the amplifier front panel. The power status indicator (2) illuminates
in blue. The amplifier is in the operational mode.

Note

The initial power-up phase lasts approximately 30 seconds from the moment the back panel power breaker
switch is placed in the up position. If the power button is pressed during this period, the power status indicator
flashes blue for the remainder of the initial power-up phase. When the initial power-up phase is complete, the
power indicator illuminates in blue and is no longer flashing.The amplifier is in the operational mode.

3. With the preamplifier muted or volume control completely lowered, select a source.

4. Increase the volume control to the desired listening level.

5. To turn the amplifier off, place it in the stand-by mode by pressing the power button on the front
panel. The power status indicator turns green, and the amplifier is in the stand-by mode.

It is now safe to turn off the rest of the system.

Powering off

Leave the Evolution e Series amplifiers in the stand-by mode between listening sessions. Turn the
amplifier of

f using the power breaker switch (10), and disconnect the amplifier from AC power when

the system is not being used for an extended time period.

Pin assignments for the XLR
connectors:

Pin 1 Shield (ground)
Pin 2

Non-inverting (0

°

) (hot)

Pin 3 Inverting (180

°

) (cold)

Note

Save all packing materials. If you
need to ship the Evolution e
Series amplifier in the future,
repack the unit in its original
packaging to prevent shipping
damage.

Unpacking

Getting Started

The Evolution 2250e is a stereo amplifier. The Evolution 3250e is a three-channel amplifier.

Evolution e Series amplifiers can be configured to accommodate any sophisticated music or
home theater system. In addition to manual operation, the amplifiers can be operated remotely
by a 12 V trigger, or by using the remote control of other Krell components. Balanced and
single-ended inputs are on the back panel. A protection circuit shuts the amplifier down if short
circuit or over-temperature conditions are detected.

This guide outlines the basic steps for unpacking, placing, connecting, and operating an Evolution
e Series Power Amplifier. Please contact your authorized dealer, distributor, or Krell if you have
any questions not addressed in the owner’s reference.

This CLASS I apparatus must be connected to a MAINS socket outlet with a protective earthing connection.

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

The ventilation slots on the top of all Evolution e Series amplifiers and the ventilation slots on the back of the
Evolution 302e and 400e amplifiers must be unobstructed at all times during operation. Do not place flammable
material on top of or beneath the component.

Before making connections to the Evolution e Series amplifier, ensure that it is off and the 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. Be especially careful when connecting to terminals marked
which may have hazardous voltages on them during operation.

THERE ARE NO USER-SERVICEABLE PARTS INSIDE ANY KRELL PRODUCT.

Two people are needed to remove an Evolution e Series amplifier from its shipping box safely
and easily.

1. Open the shipping box and remove the top layer of foam. You see these items:

1 Evolution e Series amplifier
1 20 amp AC power cord
1 12 VDC (12 V trigger) cable

2. Orient the shipping box so that one person stands at the front of the amplifier and one person
stands at the back of the amplifier. Both people need to grab a pair of the cardboard handle
cutouts (one pair located at the front of the amplifier and one pair located at the back of the
amplifier) and simultaneously lift the amplifier straight up, out of the carton.

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

Place the amplifier on a firm, level surface, away from excessive heat, humidity, or moisture. If you
place the amplifier in a closed cabinet, you may need to modify shelf spacing or use small fans to
increase ventilation. When the front and back of a cabinet are open, the air space between the
chassis and shelf must be unobstructed.

Place the amplifier(s) as close to the loudspeakers as possible. While balanced connections
technology permit long cable lengths, keep loudspeaker cable lengths to a minimum.

Krell Evolution 2250e and 3250e Series Amplifiers 1

Placement

1 packet containing this quick setup

guide and the warranty registration card

2250e,

3250e

KRELL

THE LEADER IN AUDIO ENGINEERING

EVOLUTION e SERIES POWER
AMPLIFIERS

Quick Setup Guide

OVERVIEW

WARNINGS

This product complies with the
EMC directive (89/336/EEC), low­voltage directive (73/23/EEC), and
Eco-Design directive for energy
using products (2009/125/EC).

This CLASS 1 apparatus must
be connected to a MAINS
socket outlet with a protective
earthing connection.

Back Panel

3 Loudspeaker Binding Posts

Stereo. One pair of

loudspeaker binding posts per
channel.
Three-channel. One pair of
loudspeaker binding posts per
channel.

4 Left and Right Single-ended

Inputs Stereo. One left

single-ended input and one
right single-ended via RCA
connectors.
Three-channel. One
single-ended input per
channel via RCA connectors.

5 Left and Right Balanced

Inputs Ster

eo. One left

balanced input and one right
balanced input via XLR
connectors.
Three-channel. One balanced
input per channel via XLR
connectors.

6 12 VDC Out/In (12 V trigger)

In. The 12 V trigger enables

you to turn the Evolution e
Series amplifier on or to stand­by from other components.
Out. The output sends 12 VDC
(12 V trigger) power on/off
signals to other Krell
components and other devices
that incorporate a 12 V trigger.

7 IEC Power Connector

Used to connect the provided
20 amp AC power cord. This
connector and power cord
must remain unobstructed for
easy removal in case of an
emergency.

8 Back Panel Power

Breaker Switch

Place this switch in the up
position to put the amplifier in
stand-by mode.

9 Balanced / Single Ended

Input Select Switch

Set this switch for the stle of
connection being used,
balanced/XLR or single­ended/RCA.

10 Speaker Fuses

The speaker fuse protects the
S-275 in case of overload or
malfunction.

Figure 3
Evolution 2250e
Stereo Amplifier
Back Panel

Figure 4
Evolution 3250e
Three Channel Amplifier
Back Panel

Krell Evolution 2250e and 3250e Series Amplifiers 3

Front Panel

1 Power Button

Press the power button to
place the amplifier in
operational mode.
Operational mode. The
power status indicator is
illuminated in blue when the
amplifier is in operational
mode.

2 Power Status Indicator

Stand-by. The power status

indicator is illuminated in
green when the amplifier is in
the stand-by mode. Green is
the standby color and
indicates an ultra low power
draw of 2 watts.

Figure 1
Evolution 2250e
Stereo Amplifier

Front Panel

Figure 2

Evolution 3250e

Three Channel Amplifier

Front Panel

2 Krell Evolution 2250e

and 3250e Series Amplifiers

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

© 2011 by Krell Industries, LLC, All rights reserved.