Krell Industries Evolution 202 Quick start guide

OWNER’S REFERENCE
EVOLUTION
EVOLUTION 202
STEREO PREAMPLIFIER
THE LEADER IN AUDIO ENGINEERING

Evolution 202 Stereo Preamplifier
Owner’s Reference, v06.0
Krell Industries, Inc.
45 Connair Road
Orange, CT 06477-3650 USA
This product complies with the EMC directive (89/336/EEC) and the low-voltage directive
(73/23/EEC).
IMPORTANT SAFETY INSTRUCTIONS
1. Read 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 install near any heat sources such as radiators, heat registers, stoves, or other appa-
ratus (including amplifiers) that produce heat.
8. Unplug this apparatus during lightning storms or when unused for long periods of time.
9. Refer all servicing to qualified service personnel. Servicing is required when the apparatus
has been damaged in any way,such as a 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.
10. The Evolution 202 preamplifier must be placed on a firm, level surface where it is not exposed
to dripping or splashing.
11. The ventilation grids on the top of the Evolution 202 preamplifier and the space underneath the
Evolution 202 preamplifier must be unobstructed at all times during operation. Do not place
flammable material above or beneath the preamplifier.
12. Before making connections to the Evolution 202 preamplifier, ensure that the power is off and
other components arein mute or stand-by mode. Make sureall cable terminations are of the
highest quality, free from frayed ends, short circuits, or cold solder joints.
13. Do not connect an RS-232 cable to the phono power port. Output from the phono power port
can seriously damage your computer.
14. Do not connect the cable from a Krell KPE phono stage to the RS-232 port.
15. THERE ARE NO USER SERVICEABLE PARTS INSIDE AN EVOLUTION 202 PREAMPLIFIER.
Please contact Krell if you have questions not addressed in this guide.
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. Evolution Bias™is a trademark of Krell Industries, Inc. and is a Krell technology
based on U.S. Patent No. 5,331,291. CAN Link™, CAST™, Evolution CAST™, and Krell Current Mode™are trademarks of Krell Industries,
Inc. All other trademarks are registered to their respective companies.
©2006 by Krell Industries, Inc. All rights reserved P/N 309158W
TEL [phone]
FAX [phone]
E-MAIL [email protected]
WEBSITE http://www.krellonline.com

3
Contents
List of Illustrations, page 4
ALetter from Dan D’Agostino, page 5
SECTION ONE: Evolution 202 Features and Technology, page 6
Features, Revolutionary Krell CAST Technology,
Definition of Terms
SECTION TWO: Unpacking and Placement, page 11
Opening the Evolution 202 Shipping Carton
SECTION THREE: Quick Start, page 13
Connecting the Evolution 202 to Your System,
Operating the Evolution 202
SECTION FOUR: Anatomy of the Evolution 202, page 15
Front Panel Description, Remote Control Description,
Battery Installation, and Back Panel Description
SECTION FIVE: Connecting the Evolution 202 to Your System, page 26
Input and Output Connections, Connection Steps
SECTION SIX: Evolution 202 Operation, page 28
On/Off and Stand-by Operation
SECTION SEVEN: Customizing the Evolution 202, page 29
Navigation Conventions, Menu Functions
SECTION EIGHT: Troubleshooting System Noise, page 43
WARRANTY, page 44
RETURN AUTHORIZATION PROCEDURE, page 46
SPECIFICATIONS, page 47

4
List of Illustrations
Figure 1, page 15
Evolution 202 Preamplifier and Power Supply Front Panels
Inset Preamplifier and Power Supply Stacked View
Figure 2, page 19
Evolution 202 Remote Control
Figure 3, page 22
Evolution 202 Preamplifier and Power Supply Back Panels

5
ALetter from Dan D’Agostino
Dear Audio Enthusiast,
Thank you for your purchase of the Krell Evolution 202 preamplifier.
The preamplifier plays a vital role in audio playback by mediating the line-level out-
put of a wide variety of source components in preparation for the amplifier’s input.
At no other point in the reproduction process is music so vulnerable to change, as
the signal level is small, and susceptible to noise and distortion.
Having always valued the role of the preamplifier in fine audio systems, I take pre-
amplifier design very seriously. I realize that, no matter how impressive an amplifi-
er’s performance; it can be no better than that of the preamplifier driving it.
My new Evolution 202 preamplifier employs a powerful, separate power supply,
Krell Current Mode gain stages from input to output, and Current Audio Signal
Transmission (CAST) receivers and transmitters. Utilizing these powerful technolo-
gies, the Evolution 202 conveys the complete range of timbre and dynamics that
comprise the foundation musical performance. Typical of my latest preamplifier
designs, the Evolution 202 preamplifier includes a thoughtful suite of menu
options and can be customized for the greatest ease of operation.
Ihope that you enjoy your new Evolution 202 preamplifier.
Sincerely,
Daniel D’Agostino
Chief Executive Officer

6
SECTION ONE
Evolution 202 Features and Technology
This section describes the innovative features and technology of the Evolution 202
preamplifier, and defines CAST and other key terms used in this reference.
The Evolution 202 Stereo Preamplifier, evolving from the flagship Evolution Two,
works to carefully transmit audio signals without damaging the ephemeral staging
and dimensional components of the music. The Evolution 202 is a two chassis
design with a separate power supply that isolates the critical audio stages for the
lowest possible noise floor. A combination of advanced technologies and inspired
design elevate the Evolution 202 preamplifier’s performance to the reference level.
Features
Preamplifier
The Evolution 202 has a 1 MHz open loop bandwidth in a zero feedback, bal-
anced Krell Current Mode design, terminating in Evolution CAST ™. CAST inputs
and outputs drive a newly designed current mode balanced input stage. Class A,
balanced circuitry is used throughout. Cascoded, current mirror input and output
stages utilize an LED voltage reference to achieve an exceptionally linear state of
operation.
There is no feedback employed anywhere in the design. A digitally controlled, ana-
log volume control is accomplished entirely in the current domain. The bandwidth
and transient response through this circuit is virtually unaffected by the volume
setting. A new, Krell-designed digital control circuit monitors and optimizes the
preamplifier’s operating parameters.
Power Supply
The separate power supply makes extensive use of electrical and magnetic
shielding to keep radiated interference out of critical preamplifier circuits. Internal
line conditioning circuitry filters RF noise on the AC power, and compensates for
asymmetric power waveforms and DC on the mains.
Power for the preamplifier’s analog stages comes from a large 170 VA toroidal
transformer, with four 8-amp bridge rectifiers and 39,600 microfarads of filter
capacitance. A dedicated 90 VA toroidal transformer powers the preamplifier’s
digital control circuitry. The preamplifier has as much power supply capability as
many stereo power amplifiers.

7
In stand-by mode, all the analog circuitry continues to operate at the same bias
current; however, the main analog supply voltages decrease by 30 percent. The
result is a corresponding 30 percent reduction in power consumption and heat
without the need to wait for the electronics to “warm up” before listening.
Revolutionary Krell CAST Technology
Current Audio Signal Transmission, termed CAST, is a revolutionary method of
connecting analog audio components for unparalleled sonic performance.
Innovative engineering combines the new Krell CAST circuitry with existing Krell
Current Mode technology to create entire CAST systems that reproduce music
with incredible range, tonality, and precision.
The Voltage Signal Transmission
and the Traditional Audio System
Traditionally, signal is transmitted in the voltage domain between two components.
In an audio system, each component is a discrete entity with unique characteris-
tics that act upon the musical signal independently. Each component is unaware
of the other components in the system. The cables that connect the components
also have their own electrical characteristics, which affect the sonic presentation
of the entire system. CAST transmission unifies individual components and inter-
connects into an electrically-linked whole. The original signal remains unaltered
from source to speaker.
CAST Basics
Here is how a CAST audio system works. Internally, each CAST source transfers,
or amplifies, current using Krell Current Mode circuitry. This current signal is then
output using CAST circuitry. When the signal is received by a CAST input, Krell
Current Mode circuitry again takes over until the signal reaches the loudspeaker.
By maintaining the musical signal in the current domain from beginning to end, an
entire CAST system behaves as if it is one component. With CAST, circuit board
properties and signal transmission aberrations between components are eliminat-
ed. Cable impedances and their effects on the transmitted signal are non-existent.
How CAST and Krell Current Mode Interact
While CAST is a new method of transferring the musical signal between compo-
nents, its origin stems from Krell Current Mode, the technology developed to
transfer the musical signal within a component. CAST combined with Krell Current
Mode takes circuitry signal transmission to the next evolutionary level. In essence,
continued

8
Krell Current Mode maintains the integrity of the signal within the component and
CAST preserves the transmitted signal between components. Together, CAST and
Krell Current Mode technologies unify separate Krell components into a single
global circuit. Krell Current Mode technology enjoys bandwidth increases up to an
order of magnitude greater than their voltage based counterparts. This dramatic
increase in circuit bandwidth delivers near perfection in the audible band that typi-
cally suffers from phase distortions in voltage circuits.
CAST Cable Construction
A CAST system uses cables manufactured by Krell and other manufacturers spe-
cially licensed by Krell. Thin and flexible CAST cables are constructed with the
same build quality as other Krell components and are aesthetically matched to the
components that Krell manufactures. An all-metal body and locking connectors
with gold contacts are part of the standard no-compromise specification devel-
oped for every CAST cable made.
Evolution CAST
By employing radical current mirror circuitry, the Evolution 202 components ele-
vate the CAST technology to another level. This advanced use of the technology
increases the linearity, transient speed, and bandwidth of the Evolution compo-
nents while reducing the distortion by an order of magnitude.
The Best Musical Performance
When you operate a CAST system, you will hear significant improvements in every
performance area: speed, precision, dynamic range, depth and width of the sound
stage, transient impact, tonal balance, harmonic distortion, and more. The goal for
CAST is the same company goal used for all Krell products. Krell strives for the
delivery of the best performance of a musical event for you, using the full expres-
sion of technology to date.
(SECTION ONE: Evolution 202 Features and Technology continued)

9
Definition of Terms
The following are definitions of key terms used in this owner’s reference:
Inputs and Outputs
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 profes-
sional 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 completely immune to induced noise from the system
or the environment.
CAST and Evolution CAST
Krell Current Audio Signal Transmission, or CAST, is a proprietary Krell circuit tech-
nology for connecting analog components, transmitting the audio waveform
between components in the current domain rather than in the voltage domain. The
speed and bandwidth provided by Krell CAST and its circuitry update, Evolution
CAST, yield accurate, realistic music reproduction, enabling connected compo-
nents to perform as if they are all part of a single circuit.
Single-ended
A two-wire input or output circuit. Single-ended connections are not recommend-
ed for connections requiring long cable runs. Use care when using single-ended
connections, because the ground connection is made last and broken first. Turn
the system off/on prior to making or breaking single-ended connections.
Operation
Off
When the stand-by/power LEDs are not illuminated, the preamplifier is off.
Stand-by
A low-power-consumption status that keeps the audio and regulator circuits at
idle. The stand-by/power LEDs are illuminated in red, when the preamplifier is in
stand-by mode. Krell recommends leaving the preamplifier in stand-by mode when
it is not playing music.
Operation
When the standby/power LEDs are illuminated in blue, the preamplifier is in opera-
tional mode and ready to play music.
continued

10
Technology
Krell Current Mode
A proprietary Krell circuit topology in which the audio gain stages of a component
operate in the current rather than voltage domain. This unique technology provides
the component with exceptional speed, and a wide bandwidth.
(SECTION ONE: Definition of Terms continued)

11
Unpacking and Placement
This section describes the procedures for safely unpacking and placing your
Evolution 202 Preamplifier. The Evolution 202 preamplifier is shipped in 1 carton
consisting of 2 chassis: 1 power supply chassis and 1 preamplifier chassis.
Opening the Evolution 202 Shipping Carton
The Evolution 202 shipping carton measures 22.3 in. (56.6 cm) wide by 23.5 in.
(59.7 cm) high by 16.2 in. (41.1 cm) deep.
Preamplifier Chassis. This measures 17.3 in. (43.8 cm) wide by 3.8 in. (9.7 cm)
high by 18.3 in. (46.4 cm) deep, and weighs 18 lbs. (8.1 kg).
Power Supply Chassis. This measures 17.3 in. (43.8 cm) wide, by 3.8 in. (9.7 cm)
high, by 17.7 in. (44.8 cm) deep, and weighs 28 lbs. (12.7 kg).
To Remove the Preamplifier from the Shipping Carton
1. Open the shipping carton and remove the top layer of foam. The carton con-
tains these items:
1 Preamplifier chassis
1 Power supply chassis
1 IEC Connector (AC Power) cord
1 12-pin DC cable
1 Remote control
2 AAA-size 1.5 Volt batteries for the remote
1 T-10 Torx wrench for the remote control
1 Owner’s Reference
2. Carefully remove the preamplifier, power supply, and accessories from the box.
3. Place the preamplifier and power supply in a safe location, and remove the
protective plastic wrapping.
4. Place the power supply chassis where you intend to use the preamplifier.
Krell recommends that you place the preamplifier chassis on top of the power
supply chassis.
SECTIONTWO
continued

12
Placement
Before you install an Evolution 202 preamplifier into your system, please follow the
guidelines in this section to select a location for your component. This will facili-
tate a clean, trouble-free installation.
The Evolution 202 preamplifier does not require a special rack or cabinet for instal-
lation. The preamplifier chassis measures 17.3 in. (43.8 cm) wide, 3.8 in. (9.7 cm)
high, and 18.3 in. (46.4 cm) deep.
The Evolution 202 preamplifier requires at least two inches of clearance on each
side, and at least two inches of clearance above the component to provide ade-
quate ventilation. Installation inside cabinetry may require additional ventilation.
AC Power Guidelines
The Evolution 202 preamplifier has superb regulation and does not require a dedi-
cated AC circuit. Avoid connections through extension cords or multiple AC
adapters. High quality 15 amp AC strips are acceptable. The use of AC line condi-
tioning devices is not recommended. The features provided by these devices are
already incorporated into the Evolution 202 power supply.
(SECTION TWO: Unpacking and Placement continued)

13 continued
SECTION THREE
Quick Start
To access the full array of available functions for the Evolution 202, please read
this entire owner’s reference manual. The abbreviated routine in this Quick Start
section will allow you to connect and operate the Evolution 202 quickly and enjoy
its basic functions.
The front and rear panels are shown in the diagrams on pages 15 and 22. Each
button or feature is labeled with a callout number, and these numbers are shown
in brackets in the sections below. (In the following instructions, the word “button”
refers to a front panel operation, and “key” refers to a remote control operation.)
Connecting the Evolution 202 to Your System
Position the preamplifier and power supply where you intend to use them in
your system. Do not move the chassis after they are connected.
1. Connect the power supply chassis and the preamplifier chassis with the 12-pin
DC cable provided, using the back panel DC power connectors (24).
2. Neatly arrange and organize wiring to and from the preamplifier and all compo-
nents. Separate the AC wires from any audio cables to prevent hum or other
unwanted noise from being introduced into the system.
3. Connect the outputs of your source equipment to the appropriate CAST (18),
balanced (15), single-ended (16), or tape inputs (17) on the Evolution 202.
4. Connect the main outputs (20) on the Evolution 202 to your amplifier’s inputs.
5. Connect the supplied AC power cord to the IEC power cord receptacle (27) of
the power supply unit.
6. Plug the other end of the AC power cord into AC power. The display (3) scrolls
through EVOLUTION 202 SOFTWARE VERSION, and the stand-by/power LEDs (7) illu-
minate red, indicating that the Evolution 202 is in stand-by mode. When the
scrolling stops, the Evolution 202 is ready to be powered on.
Note
Use only the power cord provided with the preamplifier to make the connection to AC
power. Operation with a power cord other than the one supplied by Krell could induce
noise, limit current, or otherwise impair the ability of the preamplifier to perform optimally.

14
Operating the Evolution 202
After the Evolution 202 is connected to your system and to AC power, and the
front panel display has stopped scrolling, begin operation:
1. Press the power button (1) on the front panel, or the remote control power key.
The standby/power LED turns blue. The display shows the factory default
input: S-1, and level: -INF. The Evolution 202 is now in the operational mode.
2. With the preamplifier output muted, or the volume fully attenuated, select a
source manually using the front panel input select buttons (8, 9, or 10) or the
remote input select keys. Start playing the source. Use the level control knob
(14) or the remote level keys to set the volume to a comfortable level.
3. To return the preamplifier to the stand-by mode, press the power button (1) or
remote power key.
Krell recommends leaving the Evolution 202 in the stand-by mode when it is
not playing music.
(SECTION THREE: Quick Start)

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SECTION FOUR
Anatomy of the Evolution 202
This section describes the Evolution 202 Preamplifier functions.
Figure 1 Evolution 202 Preamplifier and Power Supply Front Panels
1Power Button
7Stand-by/Power LED
2Infrared Emitter
4Infrared Sensor
3Front Panel Display
5Menu Button
6Enter Button
8Single-ended Input
Selection Buttons
9Balanced Input
Selection Buttons
10 CAST Input Selection Buttons
11 Tape Button and LED
12 Mute Button and LED
13 Phase Button and LED
14 Level Control Knob
Inset Preamplifier and Power Supply:
Stacked View
Power
continued
Input
Selectors
Display
Level
Navigate/
Customize
Mute
Phase
Remote
Functions

16
Front Panel Description
See Figure 1 on the previous page
The Evolution 202 Preamplifier is comprised of two chassis: the preamplifier
chassis and the power supply chassis. Front panel functions are described
below:
Chassis
Preamplifier Chassis
The preamplifier front panel provides power on, input and zone selection, level
control, menu functions, and status display.
Power Supply Chassis
Powerful transformers, high quality regulators, and extensive electrical and
magnetic shielding are housed in a separate power supply.
Power
1 Power Button or Key
Use this button or key to switch the Evolution 202 between the stand-by and
operational modes.
7Stand-by/Power LED
The preamplifier and power supply LEDs illuminate red (stand-by) when the
Evolution 202 is plugged into a standard AC wall receptacle. They illuminate
blue (operational mode) when the power button (1) is pressed while the
Evolution 202 is in stand-by mode.
Remote Functions on the Front Panel
2 Infrared Emitter
The stand-by/Power LED (7) flashes when the Evolution 202 sends signals via
this infrared emitter to a programmable remote control, such as the Universal
Krell Touch Screen Remote. See IR Out Control, on page 36.
4 Infrared Sensor
The infrared sensor receives commands from the Evolution 202 remote control.
For proper remote control operation, make sure the infrared sensor is not cov-
ered or obstructed.
(SECTION FOUR: Anatomy of an Evolution 202 continued)

17
Preamplifier Functions
8, 9, 10 Input Select Buttons or Keys
Use these buttons to select the corresponding rear panel input that is connect-
ed to a CAST (C-1, C-2), balanced (B-1, B-2), or single-ended (S-1,
S-2, S-3) analog source. The front panel display shows the selected input and
volume level.
11 Tape Button and LED, or Key
Use this button or key to select the tape input that is connected to an analog
tape source. The red tape LED illuminates when the tape input is selected. The
front panel display (3) shows: TAPE and the main volume level.
12 Mute Button and LED, or Key
Use this button or key to mute the preamplifier output. To unmute, press the
mute button again. The red mute LED illuminates when mute is selected. To
customize mute operation see Mute, on page 37.
13 Phase Button and LED, or Key
Use this button or key to invert the absolute polarity of the main output by 180
degrees. The red phase LED illuminates, when phase is selected.
Display
3 Front Panel Display
The front panel display provides preamplifier channel status messages, includ-
ing input status, tape output status, volume level, balance offset, and menu
selections.
continued

18
Level Control
14 Level Control Knob or Level Keys
Use this knob or keys to increase or decrease system volume level or, with the
balance key (C), to adjust balance. The level control knob or keys also select
menu options that customize the Evolution 202. See Customizing the
Evolution 202, on page 29.
Navigate/Customize
5 Menu Button or Key
Use this button or key to access the menu functions of the Evolution 202. For
more information, see Customizing the Evolution 202,on page 29.
6 Enter Button or Key
Use this button or key to configure the menu functions of the Evolution 202.
For more information, see Customizing the Evolution 202,on page 29.
(SECTION FOUR: Anatomy of an Evolution 202 continued)

19
Figure 2 Evolution 202 Remote Control
1Power Key
5Menu Key
6Enter Key
8Single-ended Input
Selection Keys
9Balanced Input
Selection Keys
10 CAST Input Selection
Keys
11 Tape Selection Key
12 Mute Key
13 Phase Key
14 Level Keys
AAmp Pwr Key
BAmp Sel Key
CBal(ance) Keys
DTransport Keys
EMenu Key
FDirection Keys
GSelect Key
HCD Key
IDVD Key
JTitle Key
Power
Input
Selectors
Level
Navigate/
Customize
Mute
Phase
Balance
CD and DVD
Functions
Amplifier
Functions
continued

20
Remote Control Description
See Figure 2 on the previous page
The Evolution 202 remote provides the same power, preamplifier, level control,
and navigate/customize functions as the preamplifier’s front panel. In addition,
the remote has CD and DVD functions, and menu configuration functions.
Keys Labled 1 to 14
These remote keys have the same function (and callout number) as the
corresponding front panel controls described in the preceding pages.
Keys Labled A to J
These remote keys have functions that are unique to the remote control,
and are described below.
Battery Installation and Removal
The remote control uses 2 AAA-size 1.5 Volt batteries. Batteries are included
with the shipment. To install the batteries:
1. Remove the remote control backplate, using the supplied T-10 Torx
wrench.
2. Install the batteries, following the battery position diagram on the plastic
battery receptacle.
3. Replace and secure the backplate.
Notes
Replace batteries when remote control function becomes intermittent.
Remove batteries if the remote control is not used for a long period of time. Battery
leakage can damage the remote control.
Amplifier Functions
A Amp Pwr Key
Use this key to activate Krell amplifiers connected to your system.
B Sel (Meter Select) Key
Use this key to select the meter range of the power meter scale on the
front of a Krell Evolution One power amplifier. Please refer to the Evolution
One Owner’s Reference, for more information.
(SECTION FOUR: Anatomy of an Evolution 202 continued)