M441M — Channel Amplifier

The M441M Channel Amplifier is a plug-in, high performance module which forms the foundation of sophisticated console systems. The module is designed to integrate with the Ward-Beck group of modular console components_ The M441M Channel Amplifier provides the following major functions: preamplification of a microphone source selection of a line input sensitivity and phase reversal adjustment to either the mic or line source reverb send selection (pre or post fade) and mix control foldback select and mix control solo select channel "ON' switch booster amplification following the mixer attenuator The input selector switch provides microphone sensitivity selection from 7CdBm to 20dBm in steps of 1OdB, for a standard nominal output level of OdBm: The line input posi tion provides range of sensitivity from 10dBm to +8dBm_ Sensitivity adjustments made by the rotary selector are combination of pre- amplifier feed back and input pad selection.

By this means it is possible to improve signal to noise with decreasing input sensitivity as well as maintain the highest overall dynamic range for the channel amplifier input circuitry. The microphone input is designed for operating from a 150 ohm source and the Iine input is designed to operate from a 600 ohm source or lower. Both inputs are balanced to ground with the microphone input providing an input impe- dance of 1500 ohms or greater to the source and the line input a 20k ohm bridge to the source.

The M441M is entirely balanced, and is particularly immune to radio frequency interference in high fields. The maximum preampli ifier output capability of +25 dBm provides a headroom of 35 dB before the fader. FEATURES: Modular_ plug-in construction faci- litates convenient future expansion of console input channels_ Multi-position input selector pro- vides sensitivity and automatic mic or line source selection: Compact design incorporates phase switch, reverberation selector clw independent mix control cue or solo pushbutton, foldback controls and illuminated channel-on push button.

Wide band, high dynamic range, RF isolated, electrostatically shielded input transformer Totally balanced circuitry provides transient free operation and offers high RF immunity_ Exceptionally low input noise; high peak output capability

The M44IM Channel Amplifier i5 plug-in, high performance module which Torms oundanam suphsticuied causole Sstem; The module designed intedrall Vil Ward-Beck group modulai consoe comnonents The M441MM Channe Amnlifier provides the following major Tunclions: preamnlification of microcone {ouc selection of inpul Sensi and onisl [eversa adjustment ta either the mic Tine source reverb send lection (pre post farel and mix control aldback Eontro splant channe ON" swvitch booster amplification followiny thie mixer attenuator The input selector switch nrovides microphone sensitivity selection from 7CdBm 20dBm steps TOdB standard fominal oulput level af I(NBm; The line input position provides FalYC sensitivity fram TOdBin [0 8dBin Sensitivity adjustments made by the rotary selector are combination of pre amplifier feed Duck jnu inpul JJu %clectian this Means, nossible 10 improvC Suetal HOISC 'ilh decreasing input sensitivity we maintain the highest overal dynamic range For the channel amplifier iOput circuily The microphone Inoui desigred for operating Fom 150 ohm solcce HAre itpjut designed aperate irom 600 onm source lowver Bath inputs halanced drotno wich the microphone input providing an input impe dencr of 1500 chms (catcr thc suurc and the line Input 20k ohm oudce souicc FEATURES: Modular, plug-in construction taci- litates convenieni fuiure XDansion consal npul charinels: Multi-position innut selecto vides sensitivity and automatic mic Iine source lection; Compact design incorporates phase suuch reverberation selector Ciw Inollenden control pushnuntom foldhack controls and iIluminated charnel push button: Wide band, high dynamic range isolated; electrostatically shielded indut anstorme Totally halanced circuitry provides transient free operalion and offers Huigh RF immunity Exceptionally low input noise , high peak output capability, The M441M antirel Daiancer and particularly iminune radio frequency Interterence in high fields.

The maximum preamplifier oulput capability of +25 CBM providcs hcatonm 35 UB before the fader- Neverd

SOURCE IMPEDANCE Microphone input 150 ohms balanced GAIN Line input 600 ohms or less balanced a) Preamplifier Booster amplifier input 600 ohms or less balanced Microphone input 6OdB to 1OdB +0. SdB selectable via INPUT IMPEDANCE sensitivity switch_ Microphone input 750 ohms or greater balanced_ b) Line input unity to 18dB + 0.5dB selectable via sensitivity Line input 20K ohms balanced (may be externally terminated switch.

in 600 or 150 ohms) . b) Booster amplifier 1SdB + 0.25dB Booster amplifier input 4000 ohms balanced_ FREQUENCY RESPONSE OUTPUT LEVEL +0.25dB 30Hz to 2OkHz Preamplifier 1OdBm nominal_ +27dBm maximum: NOISE Booster amplifier 1OdBm nominal, +20dBm maximum: Microphone input equivalent to -124 input noise for 70 sensitivity LOAD IMPEDANCE Line input greater than 75dB signal to noise (referred to a test level Preamplifier 600 ohms balanced.

1OdB above the nominal operating level) . Booster amplifier 600 ohms balanced_ TOTAL HARMONIC DISTORTION OUTPUT IMPEDANCE: Less than 0.25% 30Hz to 20kHz measured with preamplifier out Preamplifier less than 25 ohms. Booster amplifier less than put level of +24dBm and a booster amplifier output level of +18dBm. 25 ohms INPUT LEVEL PHASING Microphone input 70dBm to 20dBm nominal, -35dBm to +1SdBm The numbered terminal of the input pair is in phase with the maximum: numbered terminal of the output pair.

Line Input -1OdBm to +8dBm nominal, +25dBm maximum_ POWER REQUIREMENTS Booster amplifier input -25dBm nominal, +SdBm maximum: 48Vdc regulated 65 ma AMBIENT TEMPERATURE ACCESSORIES: 0 to 600C DIMENSIONS 1.6"W x 6.625"H x 6.5"D WEIGHT 1.5 Ibs_ WARD-BECK SYSTEMS LTD_ WARD-BECK SYSTEMS INC. 841 Progress Ave,Scarborough,Ont; MH 2x4 29O Larkin St; Buffalo; New York 14210 Telephone: (416) 438-6550 Telex: 06-23469 WBS

SOURCE IMPEDANCE Microphone input 150 ohms bal uncd Line input G00 chms Hesshlanced GAIN Booste amplit input G00 ohms balanced, Prcamplifier Microphone Inuut 60d8 10dB 0.5dB selectable via INPUT IMPEDANCE llvity switch Microphone input 750 ohms greatcr balanced: Line inpu uy to - 18d8 0.5dB ble via sensitivity Line Input 20K ohms halanced (may externally terminated sitch 600 50 ohms) Buaslet umplifier T5dB 0.25dB Booster amplifier HOprt 40CD ohms balanced: REQUENCY RESPONSE OUTPUt LEVEL 40.25d8 30H2 t0 20kHz Preamplifier - 1O Bmnominal, +27dBm maximum.

Booete NoISE amplifier - IOdBminominal; + ZOdBm maximuma Microphone innut equivalent t0 .124 input noise for .70 sensitivity LOAD IMPEDANCE ineinput greater than 75dB signal to noise (referred test luvel Preamplifier 600 ohms balanced: JOdB atov tIc nomina operatino leve Booster amplifier 600 ohms balancd: TOTAL HARMONIC DISTORTION OUTPUT IMPEDANCE: Less than 0.25%0 30H2 t0 ZOkHz measured with preampli fier our Preampllifier Iess than 25 ohms.

Boostcr amplifier than evel +24dBm , noosier ampli fier Output levcl of + I8dBm. 25 ohns INPUT LEVEL PHASING Microphone input 70dBm 20 Bm nomintal; '5dBm t0 15dBm The numbeted terminal of the input pair phase with the mm numueicd (C(minai na oupuL Dalll Line Input OdBm to +8dBm nominal, +25dBm maximum: POWER REQUIREMENTS Buneio[ inout ~25dBmnominol, 48Vdc requlated 65 amplifier SdBm maximum: AMBIENT TEMPERATURE ACCESSORIES: 60OC DIMENSIONS 1.6"W x 6.625"H * 6.5"D WeIGHT 5lns WARD BECK SYSTEMS LTD: WARD BeCK SYSTEMS INC_ 840o A2.Bc FCLEAOnt Mh Ex4 220 Cukn Exrmd 14210 1231 2336550 De-eaden Wbspste WBS

GAIN a) Preamplifier Microphone input 6OdB to 1OdB + 0.SdB selectable via sensitivity switch. b) Line input unity to 18dB + 0.5dB selectable via sensitivity switch. b) Booster amplifier 1SdB + 0.25dB FREQUENCY RESPONSE +0.25dB 30Hz to 2OkHz NOISE Microphone input equivalent to -124 input noise for -70 sensitivity Line input greater than 75dB signal to noise (referred to a test level 1OdB above the nominal operating level) TOTAL HARMONIC DISTORTION Less than 0.25% 30Hz to 20kHz measured with preamplifier out- put level of +24dBm and a booster amplifier output level of +18dBm INPUT LEVEL Microphone input -7OdBm to 2OdBm nominal, -35dBm to +15dBm maximum: Line Input -1OdBm to +8dBm nominal, +25dBm maximum: Booster amplifier input -25dBm nominal, +SdBm maximum ACCESSORIES: WARD-BECK SYSTEMS LTD- WARD-BECK SYSTEMS INC _ 841 Progress Ave,Scarborough, Ont.

M1H 2x4 290 Larkin St;, Buffalo; New York 14210 Telephone: (416) 438-6550 Telex: 06-23469 WBS