Krell Industries KSA-100S Quick start guide

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KSA-100S / 200S/300S OWNER’S REFERENCE

INTRODUCTION
Thank you for your purchase of the KRELLKSA-100S/200S/300S power
amplifier. These amplifiers represent the latest evolution in amplifier
technology, matching unprecedented performance with convenience not
obtainable from most high performance audio designs.
Throughout this Reference wewill refer to all three of the amplifiers as KSA.
All three amplifiers operate identically, while their sonic characteristics,
specifications, and dimensions vary. Specific differences will be described
in detail.
To obtain the best performance from your KSA, careful attention should be
paid to placement, installation and operation. A thorough understanding of
these details will help insure satisfactory operation and long life for the KSA
and related system components.
This Owner’s Reference is divided into several sections, each designed to
perform a different function. As you read through it you will become better
acquainted with the features and functions that make the KSAseries
amplifiers a superb value. A Question and Answer section is also included
where answers to common questions are provided. Should you have any
questions or suggestions please feel free to contact your authorized dealer
or the KRELLstaff for assistance.
In the unlikely event that your KSAshould require service, you will be
pleased to know that it is backed by a comprehensive Customer Satisfaction
policy and one of the most advanced service facilities in the industry. For
detailed information on the terms and conditions of service, please refer to
the Warranty and Service section of this Reference, Warranty Registration
Card, and your authorized KRELLDealer or Distributor.
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TABLE OF CONTENTS
4 UNPACKING
5 LOCATION AND REMOTE TURN-ON
6 CABINETRY AND AC POWER CONSIDERATIONS
7 AMPLIFIER FEET AND REMOTE MASTER/SLAVE CONNECTIONS
9 INPUT AND OUTPUT CONNECTIONS
12 AMPLIFIER OPERATION
13 TURN-ONDESCRIPTION
14 SYSTEMNOISE
15 BIAS LEVEL METER
16 FRONTPANEL METERBUTTON
17 REMOTECONTROLFUNCTIONS
18 PROTECTION CIRCUITRY AND TROUBLESHOOTINGSTEPS
20 QUESTIONSANDANSWERS
22 SPECIFICATIONS
23 WARRANTYAND SERVICE INFORMATION
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UNPACKING
NOTE:Due to the extreme weight of the KSAamplifiers, it is strongly advised
that unpacking and placement is completed by at least two individuals.
1. Open the box.
2. Fold back the flaps on all four sides of the box and carefully roll it over on
to the exposed end.
3. Pull the box straight up and off exposing the foam packing material.
4. Pull the foam piece from the exposed end of the amplifier.
5. Roll the amplifier carefully onto its handles and remove the second piece
of foam.
The following items will now be visible:
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4or5
KSAstereo amplifier
Remote control
Warranty card
AC power cord
Rubber feet bottoms (KSA-300S has 5 feet)
NOTE:If any’ of these items are not included, please contact your authorized
dealer immediately for assistance.
6. Removethe plastic bag from the amplifier.
NOTE:Save all packing materials. If you must ship your KSAin the future,
repack the unit in its original packaging to prevent transit damage. Should
the unit require service, send the remote control and ACpower cord with the
amplifier.
CAUTION:Do not connect the power cord to the ACmains before completing
the Installation section.
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BASIC INSTALLATION
LOCATION
Place the KSAon a firm level surface away from excessive dirt or moisture.
When using custom racks or cabinetry, keep in mind the weight and
ventilation requirements for these amplifiers. Ideally the amplifier should be
placed as close to the speakers as possible. It is preferable to run long
balanced interconnect cables to the amplifier and keep speaker cable length
to a minimum. Speaker cable adds impedance to the load the amplifier must
drive, regardless of the cable’s gauge. All KRELLamplifiers will drive the
lowest impedances with ease, but when impedance is added due to long
cable lengths, amplifier power is literally wasted in driving the cable. Long
speaker cables reduce the maximum power that can be delivered to the
speakers.
REMOTE TURN-ON INSTALLATION
Someinstallations do not have adequate space or arrangement flexibility for
the amplifier to be placed near the speakers. To allow for this, the KSA
¯ amplifiers can be turned On or Offfrom a room other than the listening room.
This type of amplifier placement is referred to as Remote Installation. The
KSAcan be placed in a room or space close to the speakers, but out of sight,
and turned On and Off from the listening room. There is a provision
internally to allow the amplifier to be controlled from a wall ACreceptacle
and not from the front panel power switch or remote control. Wesuggest a
standard wall switch be mounted in the listening room to control an AC
power outlet dedicated to the power amplifier. This can be accomplished by
an electrician. Please contact your dealer for assistance.
NOTE:Whenset-up for remote turn-on, the front panel power switch will not
operate, nor will the power switch on the remote control. The meter switches
on the front panel and remote are not affected and will operate normally.
NOTE: Remember to keep speaker cable lengths to a minimum.
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BASIC INSTALLATION
CABINETRY CONSIDERATIONS
High bias amplifiers dissipate much of the power they consume in heat.
Because the KSA-100S/200S/300S utilize Sustained Plateau Biasing, they
remain cool when not in use. Whenthe KSAis in use, it can become quite
hot. Therefore, the KSAshould be installed in a location that provides
unobstructed ventilation. If you must install the unit on shelves or in a
cabinet, extra ventilation may be necessary. This often can be accomplished
with cabinet shelf spacing or unit location. In more extreme instances the
use of small fans can aid in removing excessive heat from internal spaces.
Consult your dealer for assistance.
Generally, with the front and rear of a cabinet open, 3-4 inches of clearance
on each side and 8 inches of vertical clearance, the amplifier should have
adequate ventilation.
The KSAamplifiers have very large power supplies. As a consequence the
amplifiers are quite heavy. Whenpurchasing a rack or cabinet, keep weight
in mind. Most racks are not capable of withstanding the weight of these
units.
The exact weight and dimensions for the KSA-100S/200S/300S are in the
Specifications section of this manual.
AC POWER CONSIDERATIONS
The KSAshould have a dedicated 20 amp line and should only be operated
with the power cord supplied. Use of other power cords may damage the
amplifier and void its warranty. Please consult KRELLor your dealer
BEFOREusing any devices designed to alter or stabilize the ACpower for the
KSA. AC line filters and/or stabilizers must meet or exceed the power
transformer size in the amplifier. As an example, the line conditioner will
require a supply reservoir greater than 2800 VAto condition a KSA-200S.
If you have any questions about placement or ACpower conditions, please
consult KRELL.
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BASIC INSTALLATION
AMPLIFIER FEET
The feet on the KSAcan be used in several different ways. They are made from
machined Delrin and are supplied with separate threaded rubber bottoms.
The rubber bottoms can be screwed into the feet for protection of fragile
surfaces such as hardwood floors or furniture. For use on rugs, we
recommend using the feet without the rubber bottoms. KSAfeet can also
accept the KRELLAMDs(Acoustic Mass Damper). The AMDis a type
spiked foot that threads into the bottom of the foot. These improve the
amplifier’s sonic performance in most installations and are particularly
effective on carpeted floors. Please contact your dealer or KRELLwith any
questions.
REMOTE, MASTER/SLAVE CONNECTIONS - LINKING MULTIPLE
AMPLIFIERS
There are two Remote connectors on the back of the KSAlabeled Master and
Slave provided for linking multiple amplifiers together. Whenthe Master/
Slave cables are connected to each of the amplifiers involved, their meter
function controls and On/Off capabilities will be linked and controlled from
one amplifier.
Select the amplifier that you want to receive operation commands. That
amplifier will be the Master. Follow the instructions below for connecting the
amplifiers. Consider the Master receptacle the output and the Slave recep-
tacle the input.
1. Turn all of the amplifiers Offand unplug them from the ACwall receptacle.
Plug the amplifiers back in but do not turn them on before starting. This
ensures all amplifiers are synchronized when the cabling is connected.
Connect one end of the linking cable to the Master output on the back panel.
2. Connect the other end of the linking cable to the Slave Input on the second
amplifier.
3. To synchronize three amplifiers, connect a second linking cable to the
Master output on the second amplifier. Connect the remaining end to the
Slave input on the third amplifier.
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BASIC INSTALLATION
4. Connect additional amplifiers as described in step 3.
5. Whenthe cables are all in place, point the remote control at the amplifier
designated as Master and press the Power button. The amplifiers will all turn
on at the same time.
The meter display for each amplifier may vary. Manually change the meter
display via the front panel until all of the meters match. The amplifier will
remember the meter setting when cycled On/Off via the remote control or
front panel switch. If the unit is unplugged the memorywill not remain and
the meters may need to be resynchronized. Whenlinked and synchronized
correctly, ON/OFFand meter functions will happen simultaneously only
when the remote control is used.
NOTE: Each individual amplifier canbe turned ON/OFF and have meter
functions changed via the front panel separately. If you change an individual
amplifier’s function, it needs to be manually changed back to follow the
functions of the other amplifiers so the synchronization remains intact.
NOTE: Contact your dealer or KRELLIndustries to obtain remote cable
links.
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CONNECTIONS
INPUT AND OUTPUT CONNECTIONS
CAUTION:When making connections to this component or any other, make
sure the power amplifier is OFF and the preamplifier is in the MUTEor
STAND-BY mode.
The wiring to and from the amplifier, and all components in, general, should
be arranged in a neat, organized manner. Specifically, ACwires should be
separated from audio wires. This practice avoids hum or other unwanted
noise from being induced into the system.
1. Connect the speaker cables to the amplifier’s output terminals.
The KSAutilizes two custom sets of parallel binding posts for the left and
right channels respectively. This configuration makes cable connections
and bi-wiring simple. The binding post will only accept a spade lug or ring
terminal of proper inner radius. Bare wire, banana lugs or pins will not work.
Each binding post is labeled either (+) or (-) between the sets of posts on
rear panel. The (+) sign between the binding posts indicates the positive
output terminal. This is commonly referred to as red or hot. The (-) sign
between the binding posts indicates the negative output terminal. This is
commonly referred to as black or ground.
CAUTION:Makesure all cable terminations are of the highest quality, free
from frayed ends, shorts or cold solder joints.
2. Connect the interconnect cables from your preamplifier to the input of the
KSA.
The KSAhas balanced and single-ended inputs ’. The balanced inputs use 3-
pin XLRconnectors and the single-ended inputs use standard RCAconnec-
tors. Werecommenduse of balanced interconnects sonically, and electrically
because of their ability to reduce noise and not incur significant sonic loss
due to extreme cable lengths.
CAUTION:Use only one input to the amplifier at a time. The KSAis shipped
with shorting pins in the XLRinputs. These pins should remain in the XLR
inputs if you are operating the KSAin the single-ended mode. When the
shorting pin is inserted, pin 1 and pin 3 are shorted together. The shorting
pins must be removed to connect the KSAfor balanced operation.
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CONNECTIONS
The pin assignment for the XLRis:
pin 1 = shield (ground)
pin 2 = non-inverting input (hot)
pin 3 = inverting input
NOTE:The RCAcenter conductor for each channel is wired in parallel with
pin 2, the non-inverted input. Only one of these inputs should be connected
to a preamplifier. Do not attempt to use the single-ended and balanced
inputs simultaneously.
3. Insert the ACpower cord into the receptacle located on the back of the
KSA.Insert the other end into the wall ACreceptacle. (Refer to the Basic
Installation section, for ACpower requirements)
4. The amplifier is now ready for operation. Should you have any questions
regarding system set-up, contact your dealer or KRELLIndustries.
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