MANUAL ADM20

Gesellschaft für digitale Studiotechnik mbHSpecialists for Digital Studio Technology

ACTIVE DIGITALE

REFERENCE- STUDIOMONITOR

KSDIGITAL

GESELLSCHAFT FÜR DIGITALE STUDIOTECHNIK

AM DÖRRWALD 566571 EPPELBORN (DI)E-MAIL: INFO@KSDIGITAL.DE

WWW.KSDIGITAL.DE

FURTHER INFORMATION AVAILABLE AT:WWW.KSDIGITAL.DE

STAND: 01.06.2006

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INHALTSVERZEICHNIS

2 CONTAKT

3 CONTENTS

4 SOUNDS RIGHT IN ROOM AND TIME

5 KSDIGITAL - FEATURES OF THE ADM - FAMILY

6- 8 ADM20 - HOW IT WORKS

9 ADM20 - REAR VIEW / CONTROLS

10 ADM20 - DIAGRAMS

11 ADMW - THE THIRD WAY

12 CONNETCIOS

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SOUNDS RIGHT IN ROOM AND TIME

KSDIGITAL GESELLSCHAFT FÜR DIGITALE STUDIOTECHNIK MBH

KS DIGITAL – SPECIALIST FOR DIGITAL STUDIO TECHNOLOGY

For more than 20 years, KS has created world class sound transmission devices and hasalways followed one aim; the reproduction of genuine and natural sound. KS products canbe found in the inventory of the most illustrious operas, such as the Semperoper in Vienna,the Alte Oper in Frankfurt, Schauspiel Frankfurt, Kammerspiele in Munich or also in theHouses of Parliament in Berlin etc., as well as in the sound studios of top artists like StevieWonder, Herbert Grönemeyer, Xavier Naidoo / M. Herberger and many more. Naturally, youwill also find our products in many radio stations in Germany like SWR, SR, Hit-Radio FFHand also around the world as well as in many famous mastering studios. The guiding principlefor the design was the ultimate aim of sound neutrality that has made the ADM products anincorruptible tool in judging acoustic reproductions coupled with wonderful speakers to enjoythe results of those efforts.Many innovative ideas and patented processes have been developed by Ksdigital to get asnear as possible to the original. We developed the FIRTEC ™ technology – a digital phasecompensation filter – for the studio loudspeaker “system” (cabinet and electroniccomponents), with our dipole bass we have achieved a directional radiation, with DMC ™we have built a linear phase and zero latency cone loudspeaker and with NeXT ™ we haveintroduced a new technology that, especially in the area of mastering, has brought the eareven closer to the sound and revolutionized acoustic radiation. You have made a superbchoice in buying an ADM product from KSdigital and we congratulate you on your purchaseand wish you endless enjoyment with the equipment.

ATTENTION TO THE FINEST DETAILDuring the development of the ADM family of products, we paid special attention to thecorrect timing of the radiated acoustic signals. When an impulse is correctly radiated withzero latency, this is equivalent to a linear frequency and phase characteristic. The highlyresponsive drivers we use, that have been manufactured in Germany according to ourown, high specification, combine with the speed of the utilized MOSFET technology in ouramplifiers and the FIRTEC ™ digital equalization (ADM20) in an almost ideal way to achieveour goal of sound neutrality.

(eW ) : beim Patentamt München eingetragenes und geschütztes W arenzeichen

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KSDIGITAL – FEATURES OF THE ADM PRODUCT FAMILY

All products of the ADM family are compatible with each other. In this way it is possible tocombine the ADM 20 or ADM 30 with the ADM W or operate them together in a 5.1Surround setup.

ANALOG INPUT: Symmetrical XLR input (20dBu head room) with a bypass connector toconnect the ADM W. A blue LED indicator on the front warns of possibleoverloading.

DIGITAL INPUT: “FullScale” results in full volume. Warning, when connected directly toFullScale level such as the output of a CD-player, use the remote control toadjust the volume!

INPUT CONTROL: If the –3dB Fs limit is exceeded (-3dB under the overload limit), the blue LEDon the front will blink until the –3dB limit has been reached again. This ensuresthat you can listen in safety and that overload distortion caused by levelsabove the FullScale limit is eliminated. In case the FullScale level is accidentallyexceeded, a built-in limiter intercepts a dangerous overload and prevents thedestruction of the loudspeaker’s driver.

INPUT SWITCH: A dial at the rear of the cabinet enables the user to browse through a menuwith a number of adjustment parameters. If a parameter needs to be adjusted,this is possible by pressing the dial and rotating it until the required value hasbeen set. In this way, under “Digital In Left” or “Digital In Right” the requiredinput data can be chosen for the signal processor of the DSP. If both inputsare activated, then a mono signal is generated and reproduced.

REMOTE CONTROL:The remote control permits a control of the volume from your work areawithout a reduction of the word length of the input signal.There are 3 types of remote control:- per PC with remote control softwareThis permits access to all signal processing parameters that canalso be adjusted with the dial on the rear panel of the cabinet.- per analogue hardware controllerThis is connected to the loudspeaker and drives a VCA input signal tocontrol the amplification of the output stage.-per digital hardware controllerIn the same way as the PC software, this permits access to all signalprocessing parameters that can also be adjusted with the dial on the rearpanel of the cabinet. 5

ADM20 THE REFERENCE CREATED BY DIGITAL PRECISION

The ADM20 is an active, two-way studio monitor for medium to high volume levels. The signalprocessing, including equalization, crossover and correction of the transient behaviour of thecomponents, is completely done at the digital level. A connection to an existing, digital studioenvironment can be made digitally using the AES3 interface. An analogue feed is however, alsopossible; a high quality 27 bit gain staging, sigma-delta Converter with 64 x oversampling and adynamic of more than 130 dB is responsible for the conversion. The digital signal is furtherprocessed by a fast 60 MHz floating point Sharc DSP in our proprietary designed processor board.This converts the 24 bit wide input data into a float word with 32 bit mantissa and 8 Bit exponent thattheoretically allows a dynamic of over 1500 dB; noise from overloading, scaling and rounding offare therefore eliminated. A patented system (Pat. Nr: 198 23 110) raises signals with a word widthof less than 24 bits to an audiophile level. Parameters that can be externally adjusted, such asvolume, filter etc., work directly at the floating point level in the process so that also at this stage,e.g. when adjusting the volume, no scaling errors occur. On the output side, the DSP works withtwo 24 bit D/A converters feeding the high performance MOFSET output stage, that is equippedwith individually selected transistors. With a bandwidth of 100kHz and a rise time of 80 V/us, theoutput stage performs to 100W in treble range and 200W at deep mid-range. The resulting soundpressure is 116dB cont. and 122dB peak.

SPECIFIC FEATURES OF DIGITAL SIGNAL PROCESSING

Digital signal processing must meet the following requirements:- Separation of the relevant signal parts into treble and bass/ mid-range as well as the 3rd way onthe analogue output socket- Equalization of the transmission behaviour of each component- Overload protection function

Every analogue interference with the signal, - e.g. insertion of a cross-over filter or equalization ofindividual speakers - causes not only the desired change but also a change to the impulse behaviourof the system. Analogue equalization would inevitably lead to a short impulse being smudged alongthe time axis and create a later oscillation of the impulse response at the end of the equalization.Additionally, an impulse would, in turn, cause a further oscillation due to the inertia of the membrane.Putting these together cause a deformation of a right-angled input signal to a less related outputsignal characteristic. The FIRTEC ™ equalizer (Finite Impulse Response) which was developedfor and is used in the ADM20, is free of those distortions described above.

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On the contrary, the FIRTEC actually allows the processing of the Laufzeit time lapse / run time aswell as the frequency characteristic. The correction of the input signal takes place in real time byfolding the input signal with the impulse response of the equalization filter. As opposed to analoguetechnology, (that would try to correct the frequency characteristic with various filters therebyworsening the impulse accuracy) the equalization of the ADM20 works with a direct manipulation ofthe input signal to ensure absolute accuracy of the impulse – this is physically identical with alinearization of the frequency characteristics in Betrag value and phase. Overall, a correct impulsebehaviour is responsible for an apparent sound width (spaciousness), bass differentiation and acorrect localisation of the instruments in the room.

FREQUENCY CROSSOVER OF THE ADM20

The frequency crossover in the ADM20 works with a differential filter using FIR technology. Thehigh frequencies are determined as the difference between the input signal and the bass signals –this guarantees that there is always an ideal addition in the area between high and low frequencies.At the same time, the geometric misalignment of the moving coils of both drivers is exactlycompensated utilizing a run time circuit. When combined with the newly designed sound directionprinciple of the tweeter, that ensures a planar wave at the sound opening, an optimal radiationcharacteristic is guaranteed. The frequency crossover’s slope steepness of ca. 90 dB /Octaveensures no interference when listening in front of the speaker.

EQUALIZATION OF THE ADM20

To ensure the best possible equalization of the whole system, the FIR filter works on both tweeterand bass (complete filter) – including therefore, the transition band between both. The measurementsrequired to adjust the FIRTEC coefficients, take place on the complete speaker system, includingcrossover set-up of the drivers, so that the corrections include the complete geometry of the system.This procedure allows an individual calibration of the system after local installation. This meansthat any peculiarities of the monitoring room can be adjusted for in the configuration of the FIRTECequalizer. The factory default settings of the FIRTEC filter result from measurements in anacoustically inert room whereby each individual (!) driver is calibrated. In this way, all manufacturingtolerances have already been compensated for in the calibration. Of course, the perfect impulsereproduction is supported by all utilized drivers. With a Qts of the mid-/bass speaker of 0.24 longstroke and high driving power, is a distortion free reproduction of the loudest impulse peaksguaranteed just in the same way as with the 44mm membrane diameter of the ring-radiator tweeter.

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SOUND RADIATION

Just as important as a correct amplitude and phase in the frequencycharacteristic is an exact sound radiation, where the acoustic energy is radiateduniformly across the complete frequency range. The new principle of directing

the sound of the tweeter, guarantees aplanar wave at the sound opening. Thebuilt-on wave-guide then bundles theradiated sound in exactly the same wayas the midrange/bass speaker does in itstransition band to the tweeter, guaranteeinga constant radiation behaviour at thecrossover frequency. The driver of thistweeter, which is capable of high soundpressure, works with a membrane in ringform. Opposed to normal dome speakers,usually found in hifi and studio systems,

this enables the tweeter a distortion free reproduction of impulse peaks even atvery high volumes. The result of the correct digital equalization is neithercorrupted nor nullified by the drivers’ components. In case of a complete overloadof the input signal, utilization of a limiter in each path protects the componentsfrom destruction.

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THE 3RD WAY

A special feature of a two-way loudspeaker is the three-way processing of thesignal. In addition to the two-ways which are fed to the drivers via the built inamplifiers, the DSP of the ADM20 calculates a third way in order to reproducethe bass range. This extends the bass range to the lower frequency limit of 25Hz. This bass signal can be accessed at the analogue output socket and beconnected directly to the ADMW. If the ADM20 “WooferMode” in the parametermenu is turned to ON, then this output will be switched from “bypass” to “ADMequalization”. Thereby, all frequencies under 100Hz are redirected to the ADMWwhich naturally contributes to relieving the 8” drivers. Therefore, the combinationof the ADM20 and ADMW not only reaches the lowest frequencies but cansignificantly increase the volume of higher frequencies. Spitzenabhörlautstärke.The signal at the analogue output socket can naturally also be adjusted from theremote control.

Digital IN, OUT

Parameter adjustment dial withtwo-line display

Remote Control IN

Fused mains socketMain switch

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Remote Control OUT

AnalogueIN, OUT

Impulse respons without FIRTEC process Impuls response after FIRTEC process

Frequency of ADM20with FIRTEC (red)

Frequency of ADM20wthout FIRTEC (green)

Phase response ofADM20wiht FIRTEC (red)

Phase response of ADM20wihtout FIRTEC (green)

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In connection with the ADMW, the three-way combinationof ADM20 / ADM W forms a perfectly matched studiomonitor, that can effortlessly reproduce very highvolumes across the whole transmission range from25Hz to 20000 Hz. With its connection at the analogueoutput socket of the ADM20 where the corrective signalprocessing takes place, the ADMW is an integratedcomponent enabling all possibilities of parameter controlsuch as filtering, volume, digital connection etc. The KSMOSFET output stage with its ca. 500 Watt, offersenough reserves for the deepest and fullest bass,distinguishing itself with a lively impulse. In this way youcan enjoy the bass section just as it was recorded withno artificial bass generated by the loudspeaker itself.

To connect the ADMW to the ADM20:- turn “Woofer Mode” to ON (Parameter menu of the

ADM20)- connect the analogue output socket with the ADMW

ADMW THE THIRD WAY

OVERVIEW OF THE TECHNICAL SPECIFICATION OF THE ADM W

Connection via the Analogue OUT socket of the ADM20

Analogue IN, OUT: XLR-symmetrical, active bypass connectorRoom Equalization: per DSP in ADM20Drivers: 2 x 10” high performance speakersOutput Stage: 400 Watt MOSFET technologySound Pressure: 122dB cont. / 128dB peak

(ADM20/W Stereo set-up)

Dimensions (ADM W): 65 x 30 x 90cm 42Kg

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DIGITAL CONNECTIONS

The ADM20 utilizes different left and right loudspeakercabinets. The differentiation is simple due to the dif-ferent geometry of the speakers. The right speakerhas the name plate with the blue LED on the right,the left speaker’s is on the left. The different geometryis due to the directional optimisation. In this position,the tunnel not facing the listening position, causesfar fewer reflections.In a studio environment, a digital connection is madeby connecting the AES signal with the Digital INsocket of the ‘right’ speaker. The left speakeris connected to the active Digital OUT socketof the first speaker. The digital source must beconnected to the speaker with the ‘right digitalIn’ in paramter menue. Bild1: Right ADM20 Speaker

OVERVIEW OF THE TECHNICAL SPECIFICATION OF THE ADM20

AD / DA: 27 bit gain staging sigma delta, 64x over-samplingDigital IN, OUT: AES3 Format, 32 –110 KHz

XLR symmetric, active bypass connectorAnalogue IN, OUT: XLR symmetric, active bypass connector with signal selectionDSP: High performance Sharc Processor

60 MHz, 32 bit floating point, 1500dB dynamic1500 dB dynamic

Process: FIRTEC ™ equalization, FIR crossoverlimiter, preset equalization, user defined equalization, digital floatingpoint, volume control, deflection protection

Room Equalization: 2 x FIRTEC ™ preset, low and high shelving, 3 x parametric EQs,phase shifting

Drivers: 2” ring radiator, 8” carbon bassOutput Stage: 200W + 100W MOSFET technologySound Pressure: 116dB cont. /122dB peakRemote Control: optional, with gain control and input switch.Dimensions: 42 x 30 x 33 cm 19.7Kg

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digital source

ADM20 DIGITAL CONNECTION, REMOTE CONTROL

Remote Control

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to RC socket ofnext ADM20

to next ADM20 Digital IN in connetcion with ADMW:- to Analogue -In Buchse ofs ADMW- Woofer Mode in menue of: ON

Description Function Range of ValuesVolume Total volume 0dB … -31dB

Filter 1Frequency X/26 Frequency band of Filter 1 27 frequency bandsGain Relative level of the correction filter +6dB … -6dBQ-Factor Frequency bandwidth 0.1,…, 5.0

Filter 2Frequency X/26 Frequency band of Filter 1 27 frequency bandsGain Relative level of the correction filter +6dB … -6dBQ-Factor Frequency bandwidth 0.1,…, 5.0

Filter 3Frequency X/26 Frequency band of Filter 1 27 frequency bandsGain Relative level of the correction filter +6dB … -6dBQ-Factor Frequency bandwidth 0.1,…, 5.0

Low shelving 80Hz EQ +6dB … -6dBHigh shelving 12kHz EQ +6dB … -6dBDistance shift Speaker delay In meterSubwoofer Switches between 20Hz and 35Hz fgu Active / Not activePhase reversal Phasing shift of 180° Active / Not activeDigital In Left Turns on left data word Active / Not active

and turns off analogue inputDigital In Right Turns on right data word Active / Not active

and turns off analogue inputUpdate FIR Filter Facilitates transfer of a new filter Active / Not active

The 27 frequency bands (terz bands) appear in the display in the following order:

40 Hz, 50 Hz, 63Hz, 80Hz, 100 Hz, 125 Hz, 160 Hz, 200 Hz, 250 Hz, 315 Hz, 400 Hz, 500 Hz,630 Hz, 800 Hz, 1000 Hz, 1250 Hz, 1600 Hz, 2000 Hz, 2500Hz, 3150 Hz, 4000 Hz, 6300 Hz,8000 Hz, 10000 Hz, 12500 Hz, 16000 Hz.

PC Screen shot of the ADMControl Software