musikelectronic geithain RL921K User manual

musikelectronic geithain
RL 921K
RL 921K1
Instructions for installation and use

TABLE OF CONTENTS II
musikelectronic geithain GmbH RL 921K / RL 921K1
Table of contents
1 Introduction 1
2 Disclaimer 2
3 System description 3
4 Basic information 4
4.1 Guidelines 4
4.2 Safety instructions 4
4.3 Unboxing 6
4.4 Delivery contents 6
4.5 Cleaning 6
4.6 Environmental conditions 6
4.7 Guarantee acknowledgements 6
5 Positioning 7
5.1 Positioning near walls 7
5.2 Stereo operation 8
5.3 Surround operation 9
6 Set-up the speakers 10
6.1 Connecting the RL 921K 10
6.2 Connecting the RL 921K1 10
6.3 Cable connection 11
6.4 Adjustment controller 11
6.5 Status indication 11
7 Specications 12
8 Acoustic measurements 14
9 Notes 15

INTRODUCTION 1
musikelectronic geithain GmbH RL 921K / RL 921K1
1 Introduction
Dear customer,
Thank you for the trust you have put in us by buying these speakers. You decided upon a quality
product that in regard to tonal and technical characteristics complies to the utmost expectations.
The usual burn-in period is not required, because the speakers are articially aged in-house.
Please read the technical description and manual to take advantage of the capabilities
of these speakers and ensure safe operation.

DISCLAIMER 2
musikelectronic geithain GmbH RL 921K / RL 921K1
2 Disclaimer
Technical data and appearances are subject to changes without notice. Errors and omissions
excepted. Musikelectronic Geithain GmbH assumes no liability for any loss which may be suffered
by any person who relies either wholly or in part upon any description, photograph or statement
contained herein. Musikelectronic Geithain GmbH products are sold through authorized fulllers
and resellers only. Fulllers and resellers are not agents of Musikelectronic Geithain GmbH and
have absolutely no authority to bind Musikelectronic Geithain GmbH by any express or implied
undertaking or representation. This manual is copyrighted. No part of this manual may be reproduced
or transmitted in any form or by any means, electronic or mechanical, including photocopying and
recording, or by any information storage or retrieval system without the prior written permission of
Musikelectronic Geithain GmbH.
All rights reserved
Copyright © 2018 Musikelectronic Geithain GmbH

SYSTEM DESCRIPTION 3
musikelectronic geithain GmbH RL 921K / RL 921K1
3 System description
The RL 921K is based on the timeless classic design of the legendary RL901K. Not only optically but
also tonally the RL 921K follows in the steps of its older sibling. Therefore it is the optimal solution
in cases where the RL901K can not be used because of its size or short listening distances. The
RL 921K is aimed at professional users as well as music enthusiasts.
By the cardioid radiation characteristics within the frequency range from 30Hz through 250Hz
the reections on the back walls of listening rooms can be minimized. In addition the transfer
characteristic can be matched to the acoustical conditions of the reproduction room as well as to the
set-up situation by an integrated room matching lter.
The total directivity index of the monitor was optimized for very short listening distances and a base
distance between two and three metres (6′7″ and 9′10″). As the bass system a very linear 300 mm
(12″) long-throw driver in a cardioid cabinet is employed, delivering excellent impulse delity. The
100 mm (4″) cone is mounted together with the 25 mm (1″) dome tweeter coaxially in front of
the bass system allowing a precise steering of the directivity index. As a result a realistic and
steady spatial performance of the sound pattern around the listening position is achieved, with high
homogeneity and smallest possible coloration. By the great membrane area the RL921K is in the
highest degree level proof while at the same time it has the lowest distortions. Therefore the RL 921K
is a precision studio tool allowing fatigue free working for hours.
The three-channel MOSFET power amplier with electronic crossover is integrated into the back
of the cabinet and is hinged for service purposes. An intermittent LED lighting signals when the
overload limit is reached. After crossing of the maximum level the output level will be reduced by
20 dB to avoid any overloading of the components.
The RL 921K1 is a shortened cabinet variant of the RL921K, that is employed when not enough
installation depth is available. Be it a video wall or an outside broadcasting van. For maximum
exibility when choosing the mounting position the speaker is also available in a lying variant. As an
alternative to the standardly provided MOSFET amplier in an upright standing enclosure both the
19-inch compatible Class-D ampliers RL-Amplier and RL-Amplier 2 are also available.
A variety of special stands and racks is available as accessories. According xing elements have been
integrated into the loudspeaker cabinet.

BASIC INFORMATION 4
musikelectronic geithain GmbH RL 921K / RL 921K1
4 Basic information
4.1 Guidelines
This product complies to requirements of current European and national guidelines (2004/108/EG
Electromagnetical Compatiblity). The conformity is ascertained, corresponding declarations and
records are deposited with the manufacturer.
Products built by us belong to B2C-class of the WEEE guidelines and must not
be disposed with domestic waste.
4.2 Safety instructions
Like using any other electrical device you should observe the following operation guidelines, safety
instructions and warning signs to ensure optimum functionality and safety of operation!
;Read these instructions carefully.
;Keep these instructions during the life cycle at a safe place. The instructions are an important
part of the product.
;Heed all warnings. Follow all instructions.
;The product may only be used in accordance with the information provided in the user manual.
Before and during the usage of the amplier please ensure that all recommendations, especially
the safety recommendations in the user manual, are adhered to.
;Do not place this product on an unstable cart, stand, tripod, bracket, or table. The product may
fall, causing serious injury, and damage to the product.
;The heat sink must not be blocked or covered. This product should not be installed unless
proper ventilation is provided or manufacturer‘s instructions have been adhered to.
;Do not install the device near any heat sources.
;Do not expose the device to direct sun radiation.
;Do not install the device in rooms with high humidity.
;Do not try to insert anything into device openings.
;The device shall not be exposed to dripping or splashing and no objects lled with liquids shall
be placed on the device.
;Clean only with dry or slightly moistened cloth.
;Protect the power cord from being walked on,pinched or damaged in any other way. Pay
particular attention to plugs and the point where they exit the device.

BASIC INFORMATION 5
musikelectronic geithain GmbH RL 921K / RL 921K1
;Do not attempt to service this product yourself as opening or removing cover may expose you
to dangerous voltage or other hazards.
;Refer all servicing to qualied service personnel.

BASIC INFORMATION 6
musikelectronic geithain GmbH RL 921K / RL 921K1
4.3 Unboxing
The speakers are shipped in proper condition. Unpack the speaker carefully and check for visible
damages. In case of damages report them to your retailer. Keep the packaging, in case the speaker
has to be transported in the future.
4.4 Delivery contents
;Speaker RL921K / RL921K1
;Amplier enclosure (only RL 921K1)
;Speakon cable (only RL 921K1)
;Mains cable
;Technical description and user manual
4.5 Cleaning
The speaker is made of real wood veneer and needs to be nurtured in the same way as furnishings.
We advise quality wax polish to ensure durability of the veneer. Surfaces can also be cleaned with
tidy, slightly damped, fuzz-free, smooth cloth.
4.6 Environmental conditions
Ensure the following environmental conditions in your listening room:
;Operating temperature +15 °C ... +35 °C (+59 °F ... +95 °F)
;Storage temperature range −25 °C ... +45 °C (−13 °F ... +113 °F)
;Relative humidity 45 % ... 75 %
4.7 Guarantee acknowledgements
Opening the device by unauthorized personnel leads to all claims under guarantee expire. In case of
destruction by overload, misuse or outside inuences there are no claims under guarantee.

POSITIONING 7
musikelectronic geithain GmbH RL 921K / RL 921K1
5 Positioning
Our speakers do not impose special requirements neither in stereo nor in multichannel set-ups.
Nonetheless speaker positioning has inuence on listening impression because every room is
individually designed and furnished. The following advices are just guidelines that ease proper
positioning. In addition we offer a measurement service to take advantage of the capabilities of your
listening environment.
5.1 Positioning near walls
When speakers are installed near walls sound quality is physically affected. Every customary speaker
behaves as a punctual sonic source in the low frequency range, with sonic waves spherical radiated
without any constructional measures. Back wall reections are unavoidable.
The speakers RL921K / RL921K1 however utilize cardioid radiation characteristics with rearward
attenuation greater than 10dB. Because of this structural measurement installation near walls is
considerably less critical. For optimum listening experience a minimum distance of 20 cm (7.9″) to
walls and furniture should be ensured. Avoid corner installations because unwanted bass accentuation
could arise.
b
b
;Minimum distance to wall b ≥ 20 cm (7.9″)

POSITIONING 8
musikelectronic geithain GmbH RL 921K / RL 921K1
5.2 Stereo operation
The optimum position of the speakers in your listening environment is the so-called stereo triangle
(see gure). The base distance between the speakers and the distance to the hearing zone form an
equilateral triangle (stereo triangle). A distance less than 2 m (6′7″) or more than 3 m (9′10″) should
be avoided. For precise,spacial reproduction turn the speakers inside,directed to the hearing zone.
a
a a
hearing zone
60°
;Distance between speakers and your listening position a = 2 m … 3 m (6′7″ … 9′10″)
;Adjust the speaker horizontally to the height of the ear at the listening position