Krell Industries KMA-i800 Quick start guide

KMA-i800 Power Amplifier
Owner’s Reference

KMA-i800 Owner’s Reference
© 2023 by Krell Industries LLC. All rights reserved. Page 2 of 15
Table of Contents
Page
Getting Started 3
Unpacking / Placement / AC Power Guidelines 4
Front Panel 5
Rear Panel 6
Operation 8
Protection Modes 11
Specifications 12
Warranty 14
Service 15
Krell Contact Information 15

KMA-i800 Owner’s Reference
© 2023 by Krell Industries LLC. All rights reserved. Page 3 of 15
Getting Started
Thank you for your purchase of a Krell KMA-i800 component.
The KMA-i800 is a high performance monaural amplifier
incorporating all of Krell’s best technologies - iBias™ for true
Class A operation up to 800 watts per channel but without the
constant heat of traditional Class A designs, XD for low output
impedance that maintains firm control over the speakers for
hard hitting tight bass and brilliant highs, and Sym-Max which
virtually eliminates 2nd order harmonic distortion for a more
realistic 3D musical experience.
WARNING!Do not place the component where it
could be exposed to dirt or excessive moisture. The ventilation
grids on the top, bottom, and sides of the KMA-i800 must be
unobstructed at all times. Do not place flammable material on
top of or beneath the unit. When making connections to this or
any other model, make sure all components are off. Turn off all
system power before connecting the KMA-i800 to any other
component. Make sure all cables are of the highest quality,
free from frayed ends, short circuits or cold solder joints.
CAUTION! The top, sides, and bottom of the
KMA-i800 may get hot during use.
WARNING! The KMA-i800 is a differential output
amplifier. Both speaker terminals are live! The negative
speaker terminal is not connected to
ground.
This product complies with the EMC directive
(89/336/EEC) and the low-voltage directive
(73/23/EEC). This CLASS 1 apparatus must
be connected to an AC MAINS socket outlet
with a protective earthing connection.
WARNINGS
CAUTION
NO USER SERVICEABLE PARTS INSIDE.
RISK OF ELECTRIC SHOCK
DO NOT OPEN

KMA-i800 Owner’s Reference
© 2023 by Krell Industries LLC. All rights reserved. Page 4 of 15
Unpacking / Placement / AC Power Guidelines
Unpacking
The KMA-i800 is very heavy and requires two strong people to lift it and position it.
Place the shipping box on a firm level surface. Lift off the top of the shipping box and remove the small cardboard box located
in the center of the protective foam. This box contains a power cord and a 12V trigger cable. Remove the top protective
foam. The unit can now be lifted out of the bottom part of the shipping box and placed in the desired location.
Placement
The KMA-i800 may generate substantial heat while in operation and is intended for use indoors in a typical residential
environment. Place it on a firm level surface where it will not be exposed to excessive heat, humidity, dust, or moisture of
any kind. Krell recommends that it be placed in open air and not in an enclosed cabinet or rack. The bottom, sides, and
top must remain unobstructed in order to maintain adequate air flow. Do not place it directly on a deep pile carpet. It
should not be placed on top of other equipment nor should other equipment be placed on top of it. Please contact Krell if it
must be placed in a rack as forced air circulation will be required.
AC Power Guidelines
The KMA-i800 requires a dedicated AC circuit rated at a minimum of 20 amps for 100-120VAC operation or 13 amps for
220-240VAC operation. Do not use extension cords, adapters, or power strips. Krell does not recommend the use of
power conditioners with the KMA-i800.

KMA-i800 Owner’s Reference
© 2023 by Krell Industries LLC. All rights reserved. Page 5 of 15
Front Panel
1) Power Button
2) Indicator Lights
Front Panel Features Description
1) Power Button
The primary function of the power button is to switch the unit from stand-by to operate or operate to stand-by.
It may also be used to start a software update or a factory restore. See the Operation section for more
information about these functions.
2) Indicator Lights
The indicator lights provide information about the status of the unit. Solid green indicates stand-by and solid
blue indicates on. See the Operation section for more information about status.
Rear Panel
2
2
1

KMA-i800 Owner’s Reference
© 2023 by Krell Industries LLC. All rights reserved. Page 6 of 15
6
1) AC Mains Inlet
2) Power Switch
3) 12VDC Trigger Input
4) RJ45 Ethernet Jack
5) Speaker Binding Post, Positive
6) Speaker Binding Post, Negative
7) RCA (single-ended) Input Jack
8) XLR (balanced) Input Jack
1
2
3
4
5
5
6
7
8

KMA-i800 Owner’s Reference
© 2023 by Krell Industries LLC. All rights reserved. Page 7 of 15
Rear Panel Features Description
1) AC Mains Inlet
IEC 320 inlet for connection to an AC mains outlet. See the serial number label on the rear panel of the unit
for the specific voltage requirements. Use only the supplied power cord or one with an equivalent current
rating.
2) Power Switch
Move the power switch to the up position to apply power to the unit or the down position to remove power.
The power switch is also a circuit breaker. In the event of an internal fault it may automatically move to the
down position to remove power from the unit.
3) 12VDC Trigger Input
For connection to a home control system or other component with a 12VDC trigger output to switch the unit
on (+12V) or off (0V). This input accepts a 3.5mm mono plug where the tip is hot and the sleeve is ground.
4) RJ45 Ethernet Jack
For connection to a LAN (local area network) at speeds of 10/100 Mbps. This must be connected to the LAN
router in order to access the embedded web page. The router must have access to the Internet in order to get
software updates.
5) Speaker Binding Post, Negative
Connect the negative wire from the speaker to this post. The binding post accepts 5/16” (8.0mm) spade
connectors, bare wire, or banana plugs. This is internally connected to ground.
Caution! – Hazardous voltages may be present on this post when the unit is
in operation. Do not touch.
6) Speaker Binding Post, Positive
Connect the positive wire from the speaker to this post. The binding post accepts 5/16” (8.0mm) spade
connectors, bare wire, or banana plugs.
Caution! – Hazardous voltages may be present on this post when the unit is
in operation. Do not touch.
7) RCA (single-ended) Input jack
RCA jack for connection to single-ended analog audio sources (3.8Vrms maximum input
voltage). Insert the shorting jumper between pins 1 and 3 of the XLR jack when using this
input.
8) XLR (balanced) Input Jack
XLR jack for connection to balanced analog audio sources (3.8Vrms maximum input
voltage). Pin 1 is ground, pin 2 is non-inverting (+), and pin 3 is inverting (-).
Krell recommends balanced input connections for the best performance.

KMA-i800 Owner’s Reference
© 2023 by Krell Industries LLC. All rights reserved. Page 8 of 15
Operation
Power
Connect the KMA-i800 to an AC mains outlet and turn on the rear panel power switch. After about 4 seconds the front
panel indicator lights will illuminate green. The unit is now in stand-by. Wait another 8 seconds then press and release the
power button. An audible click will be heard from the unit and the indicator lights will fade from green to blue. The blue
illumination will fade out and in for about 8 seconds and then remain constant. The KMA-i800 is now ready to play. To
return to stand-by press the power button again.
Web Interface
The KMA-i800 has a Web interface that provides status information and the ability to remotely control the unit. It is easily
accessed with most commonly available Web browsers. First, with the unit off, connect an Ethernet cable from the rear
panel jack on the KMA-i800 to the LAN router. Turn on the rear panel power switch. Open a Web browser on a device
connected to the same LAN and type http://krell-kmai800-xxxx.local into the URL window (xxxx is the last four digits of
the serial number).
When the KMA-i800 is in stand-by the Web page will be grayed-out and only the Power button will be active. Click on the
Power button to turn on the unit. The KMA-i800 will turn on and a few seconds later the Web page will come up to full
brightness and various status information will be displayed.
About 15 seconds later the temperature display will appear. Channel 1 is the right side and Channel 2 is the left side.
During use it is normal for there to be a difference of a few degrees between the sides.
The No Signal Timeout feature will put the KMA-i800 in stand-by if an input signal is not detected during the selected time
period. The default setting is Disabled.

KMA-i800 Owner’s Reference
© 2023 by Krell Industries LLC. All rights reserved. Page 9 of 15
Web page KMA-i800 in stand-by
Web page KMA-i800 on

KMA-i800 Owner’s Reference
© 2023 by Krell Industries LLC. All rights reserved. Page 10 of 15
Factory Restore
This will restore any internal settings back to their factory default values. Turn on the KMA-i800 from the rear panel. Wait
2 seconds after the green stand-by lights come on then press and hold the power button until the green lights begin to
fade out and in; release the power button. After about 13 seconds the lights will go off and then come back on steady. The
factory restore is done.
If the Web interface is inaccessible and the LAN connection is good, a factory restore may solve the problem.
Software Update
Note: Upon reaching a certain point in the update process power must not be removed from the KMA-i800. If this
happens, the unit may be rendered inoperable. Read through the entire software update process before attempting to
perform a software update.
From time to time Krell may release new versions of software to add features or fix a problem. The KMA-i800 must be
connected to the LAN router with access to the Internet in order to perform the software update. With the KMA-i800 in
stand-by press and hold the power button until the green stand-by lights begin to flash; release the power button.
While the green lights are flashing the unit is checking for newer software. If they stop flashing and stay steady that
means the unit already has the latest software. If the lights change to red that means it was unable to connect to the
server to check for software updates. This can be caused by a lack of connection to the LAN or the router not allowing the
KMA-i800 to connect to the Internet.
If there is new software available, the lights will start to flash blue. The KMA-i800 is downloading the software update. If
the lights change to red that means the download failed. Sometimes this can be caused by slow response over the
Internet. Try the software update again later.
When the unit is done downloading the software the lights will flash blue with two flashes per period. The unit is copying
and verifying the software download. If the lights change to red there was a problem with the downloaded file. Try the
software update again later.
Do not turn the unit off or otherwise remove power beyond this point in the software update process!
The lights will go off at this point and then come back on blue, fading in and out rapidly. The program memory is being
overwritten. The lights will then go off briefly and then come back on steady green. The KMA-i800 is in stand-by and is
ready to use.

KMA-i800 Owner’s Reference
© 2023 by Krell Industries LLC. All rights reserved. Page 11 of 15
Protection Modes
The KMA-i800 protects itself and the attached speakers from high DC levels on the outputs (DCO), short circuits or
excessive current draw on the outputs, internal power supply faults, and excessively high temperature. The first three
conditions will result in the unit shutting off. During a high temperature condition, the unit will mute until the temperature
drops down to a safe level and then unmute.
The front panel indicator light for the side or sides affected will change to red and flash a code during a protection
condition.
FlashesMode
1 Over Current
2 High DCO
3 Power Fault
None High Temperature
If one of the first three protection modes activates, immediately turn off the rear panel power switch.
Over current protection would most likely be triggered by speaker wires shorting together or an internal short circuit in the
speaker. Check the speaker wires carefully to ensure they are not touching each other and that the positive (red) speaker
wires are not touching the case of the KMA-i800. Turn the unit on and try playing music. If the over current protection
triggers again, contact Krell for support.
High DCO can be caused by high levels of DC on the inputs or an internal fault in the unit. Disconnect the input cables
and the speaker cables and turn on the KMA-i800 again. If it stays on, turn it off, re-connect the input cables, and then
turn it back on. If the high DCO protection triggers again the problem is with the component connected to the KMA-i800. If
it does not stay on with the input cables disconnected the problem is inside the unit. Contact Krell for support.
A power fault can be caused by excessive current draw from the AC mains, usually associated with driving a low
impedance speaker at high levels, or by an internal fault in the unit. Disconnect the speaker wires and turn the system
volume down to zero. Turn on the KMA-i800 again. If it stays on, turn it off and re-connect the speaker wires. Turn it back
on and slowly increase the system volume. If it stays on until a relatively high volume level this probably means there is
inadequate current available from the AC mains outlet and the voltage is dropping too much as the volume increases. If it
stays on until a relatively low volume level this probably means that there is a partial short circuit in the speaker wires or
speakers. If it does not stay on with the speaker wires disconnected the problem is inside the unit. Contact Krell for
support.

KMA-i800 Owner’s Reference
© 2023 by Krell Industries LLC. All rights reserved. Page 12 of 15
Specifications
Analog Inputs
1 balanced via XLR connector
1 single-ended via RCA connector
Outputs
2 pr. speaker outputs via gold-plated binding posts
Control inputs
1 Ethernet via RJ45
1 12 VDC trigger input via 2-conductor 3.5 mm connector
Input impedance
Balanced: 28 kΩ
Single-ended: 14 kΩ
Frequency response
20 Hz to 20 kHz +0, -0.13 dB
-3dB bandwidth 147kHz (measured at 50W into 8Ω)
Signal-to-noise ratio
>109 dBr, wideband, unweighted, referred to full power output
>120 dBr, “A”-weighted
Gain
26.5 dB
Input Sensitivity
3.8 V RMS
Total harmonic distortion
<0.010%, 1 kHz, 800W, 8Ω load
<0.035%, 20 kHz, 800W, 8Ω load
Output power
800W RMS at 8Ω
1600W RMS at 4Ω
Output voltage
245 V peak to peak
86 V RMS
Output current
56 A peak
Slew rate
35 V/µs
Output impedance
0.009 Ω, 20 Hz
0.018 Ω, 1 kHz
Damping factor
>800, 20 Hz referred to 8 Ω
>400, 1kHz referred to 8 Ω

KMA-i800 Owner’s Reference
© 2023 by Krell Industries LLC. All rights reserved. Page 13 of 15
Specifications (cont.)
Power consumption
Standby: 1 W
Idle: 260 W
Maximum: 4750 W
Heat output
Idle: 890 BTU/hr
Maximum: 10,773 BTU/hr (4Ωload)
Dimensions
17.25 in W x 9.4 in H x 24 in D
438 mm W x 239 mm H x 610 mm D
Weight
Unit only: 145 lbs. [66 kg]
As shipped: 180 lbs. [82 kg]
Specifications subject to change without notice.

KMA-i800 Owner’s Reference
© 2023 by Krell Industries LLC. All rights reserved. Page 14 of 15
Warranty
This Krell product has a limited warranty of three years for parts and labor on circuitry from the date of purchase
extended to five years with submission of the Warranty Registration Card either online at our website, or by mail within 60
days of purchase.
Should this product fail to perform at any time during the warranty, Krell will repair it at no cost to the owner, except as set
forth in this warranty. The warranty does not apply to damage caused by acts of nature.
The warranty on this page shall be in lieu of any other warranty, expressed or implied, including, but not limited to, any
implied warranty of merchantability or fitness for a particular purpose. There are no warranties which exceed beyond
those described in this document. If this product does not perform as warranted herein, the owner’s sole remedy shall be
repair. In no event will Krell be liable for incidental or consequential damages arising from purchase, use, or inability to
use this product, even if Krell has been advised of the possibility of such damages.
Proof of purchase in the form of a bill of sale or receipted invoice substantiating that the unit is within the warranty period
must be presented to obtain warranty service. The warranty begins on the date of retail purchase, as noted on the bill of
sale or receipted invoice from an authorized Krell dealer or distributor.
The warranty for Krell products is valid only in the country to which they were originally shipped, through the authorized
Krell distributor for that country, and at the factory. There may be restrictions on or changes to Krell’s warranty because of
regulations within a specific country. Please check with your distributor for a complete understanding of the warranty in
your country.
If a unit is serviced by a distributor who did not import the unit, there may be a charge for service, even if the product is
within the warranty period.
Freight to the factory is your responsibility. Return freight within the United States (U.S.A.) is included in the warranty. If
you have purchased your Krell product outside the U.S.A. and wish to have it serviced at the factory, all freight and
associated charges to the factory are your responsibility. Krell will pay return freight to the U.S.A.-based freight forwarder
of your choice. Freight and other charges to ship the unit from the freight forwarder to you are also your responsibility.
Krell is not responsible for any damage incurred in transit. Krell will file claims for damages as necessary for units
damaged in transit to the factory. You are responsible for filing claims for shipping damages during the return shipment.
Krell does not supply replacement parts and/or products to the owner of the unit. Replacement parts and/or products will
be furnished only to the distributor performing service on this unit on an exchange basis only; any parts and/or products
returned to Krell for exchange become the property of Krell.
No expressed or implied warranty is made for any Krell product damaged by accident, abuse, misuse, natural or personal
disaster, or unauthorized modification.
Any unauthorized voltage conversion, disassembly, component replacement, perforation of chassis, updates, or
modifications performed to the unit will void the warranty.
The operating voltage of this unit is determined by the factory and can only be changed by an authorized Krell distributor
or at the factory. The voltage for this product in the U.S.A. cannot be changed until six months from the original purchase
date.
In the event that Krell receives a product for warranty service that has been modified in any way without Krell
authorization, all warranties on that product will be void. The product will be returned to original factory layout
specifications at the customer’s expense before it is repaired. All repairs required after the product has been returned to
original factory specifications will be charged to the customer, at current parts and labor rates.
All operational features, functions, and specifications and policies are subject to change.

KMA-i800 Owner’s Reference
© 2023 by Krell Industries LLC. All rights reserved. Page 15 of 15
Service
Return Authorization Procedure
If you believe there is a problem with your component, please contact your dealer, distributor, or the Krell factory to
discuss the problem before you return the component for repair. To expedite service, you may wish to complete the
Service Request Form under the Support section of our website at: www.krellhifi.com.
To return a product to Krell, please follow this procedure so that we may serve you better:
1. Obtain a Return Authorization Number (R/A number) and shipping address from the Krell Service Department.
2. Insure and accept all liability for loss or damage to the product during shipment to the Krell factory and ensure all
freight (shipping) charges are prepaid.
3. The product may also be hand delivered if arrangements with the Service Department have been made in
advance. Proof of purchase will be required for warranty validation at the time of hand delivery.
NOTE: Use the original packaging to ensure the safe transit of the product to the factory, dealer, or distributor. Krell may,
at its discretion, return a product in new packaging and bill the owner for such packaging if the product received by Krell
was boxed in nonstandard packaging or if the original packaging was so damaged that it was unusable. If Krell
determines that new packaging is required, the owner will be notified before the product is returned.
To purchase additional packaging, please contact your authorized Krell dealer, distributor, or the Krell Service Department
for assistance.
To Contact the Krell Service Department:
Telephone: [phone] Monday-Friday, 8:30am to 5:00pm EST
Fax: [phone]
E-Mail: [e-mail]
https://www.krellhifi.com