Martin Audio Wavefront W8CT Application Manual Download Page 18

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The farfield inner power amplifier channels are the reference...

Initial outer level settings

Similarly, initial outer level settings can be calculated for each row as follows:

Again, the farfield inner amplifier setting (0dB) is used as a reference...

In a fairly small, wide, fan-shaped venue with heavily raked seating, we may require
the following amplifier channel settings:

Summary of Contents for Wavefront W8CT

Page 1: ...MARTIN AUDIO L O N D O N The Martin Experience Wavefront Compact Series Applications Guide All material 2007 Martin Audio Ltd Subject to change without notice...

Page 2: ...ew Section 1 W8C 3 way System Section 2 W8CT W8CM Line Array System Section 3 W8CS Flown Subwoofer Section 4 WSX Folded Horn Subwoofer Appendix A1 W8 3 way System A2 W8S HybridTM Subwoofer Section 5 W...

Page 3: ...for damage to any returned product through the use of non approved packaging Standards Martin Audio Wavefront Compact Series products conform to the requirements of the EMC Directive 89 336 EEC amende...

Page 4: ...ed to assemble high quality truck friendly quick deployment sound systems for applications ranging from small clubs commercial and theatrical productions using floor placed W8Cs and W8CS to vast outdo...

Page 5: ...utilisation without compromising performance and reliability Wavefront W8C 3 way System The heart of the Wavefront Compact series is the award winning W8C Section 1 a compact light weight high perform...

Page 6: ...r W8C clusters by providing spot coverage for difficult seating areas The W8CT combines three horn loaded high mid drivers with six horn loaded high frequency compression drivers Like the award winnin...

Page 7: ...ure W8CS may be used as full bass subwoofers up to120Hz or may be flown as mid bass sections 60 160Hz to complement floor standing WSXs Wavefront WSX Folded Horn Subwoofer The WSX folded horn subwoofe...

Page 8: ...o product configurations including the Wavefront Compact family It is ideal for combining Wavefront Compact products into seamless systems For instance two DX1s may be used to combine W8Cs W8CS and WS...

Page 9: ...MARTIN AUDIO L O N D O N The Martin Experience Wavefront Compact Series Applications Guide Section 1 Wavefront W8C 3 Way System All material 2007 Martin Audio Ltd Subject to change without notice...

Page 10: ...Management System 1 6 Power amplifier recommendations 1 6 1 Martin Audio MA2 8 Power Amplifier Overview 1 7 General operational summary 1 8 Arraying and placement 1 9 Coverage calculations 1 10 W8Cs a...

Page 11: ...mply with the 12 1 safety factor specified by the German VBG70 standard when used with compatible 12 1 flying systems One important advantage of the MAN flying system is that inter cabinet connections...

Page 12: ...et finish Slate textured paint Protective grille Perforated steel Grille finish Grey paint Dimensions incl wheels W 562mm x H 799mm x D 925mm W 22 1ins x H 31 5ins x D 36 4ins Flown weight 69kg 152lbs...

Page 13: ...1 1 Low Mid Low Mid 2 1 Low Mid Low Mid 3 2 High Mid High Mid High 4 2 High Mid High Mid High 5 3 High n c 6 3 High n c 7 4 n c n c 8 4 n c n c see Section 1 5 for details of the connector panel Activ...

Page 14: ...tion or loss of signal 1 3 2 Recommended loudspeaker cable Cable run vs copper core cross sectional area Single W8C Two W8C paralleled at the cluster Up to 50m 2 5mm 6mm or 2 x 2 5mm cores in parallel...

Page 15: ...sections and W8CS subwoofers See the Section 1 5 for further DX1 information and Section 2 of this applications guide for a more complex example 1 4 1 Cluster sub sections When designing a large soun...

Page 16: ...W8Cs each requiring high high mid low mid power amplifier channels 8 pairs at 3 bands per pair 24 amplifier channels required 12 x 2ch amplifiers per cluster 2ch power amplifier allocations Farfield i...

Page 17: ...Initial inner level settings Initial inner level settings can be calculated for each row as follows All material 2007 Martin Audio Ltd Subject to change without notice...

Page 18: ...evel settings can be calculated for each row as follows Again the farfield inner amplifier setting 0dB is used as a reference In a fairly small wide fan shaped venue with heavily raked seating we may...

Page 19: ...usters are further from the audience at the front and require less nearfield downfill attenuation The lower the cluster the greater the required attenuation rate Again the vertical layout is In a narr...

Page 20: ...r functions suitable for a wide range of system configurations and power amplifiers DX1 Factory Preset Examples W8C Rear panel Active Passive switch Please note that the W8C rear connector panel is eq...

Page 21: ...3 way W8C system Two MA2 8s will drive four W8Cs assuming W8Cs driven in pairs The following shows the DX1 with programme 20 selected This caters for a stereo set up comprising left and right W8Cs in...

Page 22: ...ntre frequency 0Hz 20kHz 1 36 octave steps 368 positions Filter Q BW 0 4 to 128 2 5 to 0 008 Sections switched to shelving response Low frequency 20Hz 1kHz High frequency 1kHz 20kHz Shelf gains 15dB i...

Page 23: ...dBu Vrms dB dB dB dB Martin MA2 8 38dB 2 0 62 38 9 9 7 Crest CA9 x68 1 0 69 37 8 8 6 Crown MA1202 0 775v 0 0 77 36 7 7 5 1 0 87 35 6 6 4 QSC PL224 2 0 98 34 5 5 3 3 1 09 33 4 4 2 Martin MA2 8 32dB 4 1...

Page 24: ...ed to exceed the 250 300W into 8 500 600W into 4 power rating unless the amplifier s power rails are well regulated see Section 1 6 even with properly set controllers in place Although Martin Audio dr...

Page 25: ...y Gain Lomid Himid High dBu Vrms dB dBu dBu dBu Martin MA2 8 38dB 2 0 62 38 3 6 9 Crest CA9 x68 1 0 69 37 2 5 8 Crown MA1202 0 775v 0 0 77 36 1 4 7 1 0 87 35 0 3 6 QSC PL224 2 0 98 34 1 2 5 3 1 09 33...

Page 26: ...rs capable of delivering undistorted output power into a range of loads as follows W8C 250 300W AES into 8 ohms 500 600W AES into 4 ohms and 1 000 1 200W AES into 2 ohms Please note Amplifiers with in...

Page 27: ...eloping output stage crossover distortion Mains safety A fully qualified technican should check mains safety and phase voltage before the system is patched Power reserve Power amplifier specifications...

Page 28: ...vel control advanced in sequence to check system operation and patching Assuming that controller output levels and limiters have been set as tabulated in Section 1 5 2 power amplifier level controls s...

Page 29: ...nce in the operating temperatures of each output device In contrast a conventional tunnel design can result in a temperature variance of up to 40 between output devices Switch Mode Power Supply The MA...

Page 30: ...reduce the input signal proportionally Thermal Protection Thermal Protection circuitry prevents the amplifier from running at an unsafe temperature by muting the input signal when the internal temper...

Page 31: ...Hz at 500W 4 ohms 0 08 4 ohms 0 03 4 ohms 0 02 4 ohms 0 03 4 ohms 0 08 Power Matrix LOAD CONFIGURATION 16 ohms Stereo 2 channel 8 ohms Stereo 2 channel 4 ohms Stereo 2 channel 2 ohms Stereo 2 channel...

Page 32: ...calibrate its output levels controls to their 0dB nominal position initially These settings will be easier to get back to and will avoid embarrassing level setting mistakes during the show particularl...

Page 33: ...s horizontal coverage is 55 at high frequencies the system has been designed to integrate well with smaller splays for practical output summing A splay of 40 between axes 260mm between cabinet front c...

Page 34: ...ns in this applications guide on multiple columns The beauty of the MAN system is that each cabinet in a system supports only its own weight Each pair of vertical chains is attached to a single width...

Page 35: ...flown systems examples Wavefront cluster examples are included in this manual to illustrate recommended loudspeaker combinations and splay angles only Note that very large clusters particularly those...

Page 36: ...t from the lower flying point of the cabinet above ii NEVER suspend standard cabinets horizontally Two Wavefront Compact W8Cs correctly rigged using upper key holes only All material 2007 Martin Audio...

Page 37: ...vertical coverage of a W8C cluster can be calculated as follows Vertical coverage of a W8C the vertical coverage of a single W8C 30 the sum of all the vertical splay angles For a 3 deep W8C cluster wi...

Page 38: ...ertical splay angles 30 15 15 60 For a 3 deep W8C cluster with 20 vertical splay angles 30 20 20 70 The horizontal coverage can be calculated as follows For a 2 wide W8C cluster with 30 horizontal spl...

Page 39: ...er The horizontal coverage now extends to 55 30 30 30 30 30 205 for 30 horizontal splays 55 40 40 40 40 40 255 for 40 horizontal splays and the vertical coverage extends to 30 15 15 15 75 for 15 verti...

Page 40: ...o back to provide full 360 horizontal x 90 vertical coverage for ice shows for example Column View Note that the 90 coverage allows foldback to be provided to the ice dancers The centre hole may be fi...

Page 41: ...subwoofers They can focus vocals and add a detailed quality that can be beneficial right out to the mix position If the apron fill loudpeaker signal is delayed by the difference between the downfill p...

Page 42: ...quired for good projection and intelligibility W8Cs are ideal for this application as they blend in sonically without off axis lobing and stage mic colouration Deep orchestral stage continues this way...

Page 43: ...y be considered for panning spot effects around the venue Flown radial delays Flown distribution or delay loudspeakers should be placed on radii converging at the stage and staggered for smooth covera...

Page 44: ...ions will affect placement for heavily raked seating areas and intelligent compromises will need to be made Delay systems should be thoroughly checked over a wide listening area to ensure that their l...

Page 45: ...t to scale Small delay time errors are inevitable where delay towers are located in audience areas eg on a football field due to the three dimensional geometry involved Initially controller delays sho...

Page 46: ...UDIO L O N D O N The Martin Experience Wavefront Compact Series Applications Guide Section 2 Wavefront Longthrow W8CT W8CM Line Array System All material 2007 Martin Audio Ltd Subject to change withou...

Page 47: ...hing 2 5 DX1 gain limiter settings 2 6 Power amplifier recommendations 2 7 General system reminders 2 8 Coverage 2 9 Further examples Section 2a Climatic effects on sound propagation 2a 1 Introduction...

Page 48: ...rest of the Wavefront family Although designed to be rigged in continuous columns for very long throw operation Wavefront Longthrow elements may also be used within W8C clusters to provide spot covera...

Page 49: ...ine vertical see Section 2 8 Crossover 750Hz 3 5kHz Connectors 2 x Neutrik NL8 Cabinet construction Birch Ply Cabinet finish Slate textured paint Protective grille Perforated steel Grille finish Grey...

Page 50: ...rated steel Grille finish Grey paint Dimensions incl wheels W 562mm x H 799mm x D 925mm W 22 1ins x H 31 5ins x D 36 4ins Flown weight 72kg 158lb Lid 4kg 9lb extra Before rigging note colour coding W8...

Page 51: ...es and patch panels Neutrik NL connectors NL8FC 8 pole cable female NL8MPR 8 pole panel male NL8MM 8 pole inline coupler male male Connectors should be kept in good clean uncorroded condition to ensur...

Page 52: ...2 Enable the system to provide the required sound quality coverage and level without feedback and without stressing its mechanical electrical or electro acoustic components 3 Be divided into easily un...

Page 53: ...Loudspeaker Management Systems configured as 5 way crossovers Martin Audio can provide factory set configuration cards for a variety of off the shelf crossover systems contact your dealer or Martin A...

Page 54: ...t gain settings will enable full system performance to be obtained whilst keeping the console and drive system noise floors inaudible and avoiding amplifier slew rate limiting W8CT W8CM assuming 600Wc...

Page 55: ...W8CT and W8CM as long as they are sourced by a correctly set controller When choosing power amplifiers do not be tempted to exceed the 250 300W into 8 500 600W into 4 power rating unless the amplifier...

Page 56: ...ded Amplifier Amplifier Amplifier DX1 LIMITER Example Sensitivity Gain Settings dBu Vrms dB Lomid Himid High dBu dBu dBu Martin MA2 8 38dB 2 0 62 38 3 6 9 Crest CA9 x68 1 0 69 37 2 5 8 Crown MA1202 0...

Page 57: ...nufacturers keep their costs down by using unregulated supply rails which sag under load To allow for this sag manufacturers set their rails high so that they still meet their quoted output into speci...

Page 58: ...e sure that it is sinusoidal and not crawling with spikes or interference 3 Avoid driving more than one W8CT high mid or high section or one W8CM cabinet per power amplifier channel This will keep the...

Page 59: ...ier for a particular Wavefront product This avoids confusion caused by different controller topologies or by power amplifiers with different voltage gains for the same output specs 2 It is common prac...

Page 60: ...approximately 7 5 in the upper midrange When dead hung as illustrated below the vertical coverage narrows with increasing cluster height following the classic law for multi element line arrays speed...

Page 61: ...long straight column s mid and high frequency coverage must be regarded as being cylindrical in nature Low mid vertical coverage will widen in the farfield depending on the height of the column but us...

Page 62: ...base flown designs in this applications guide on multiple columns The beauty of the MAN system is that each cabinet in a system supports only its own weight Each pair of vertical chains is attached to...

Page 63: ...ont Longthrow elements may need to be flown in multiple layers to maintain the 12 1 safety factor of the standard Martin Audio Wavefront 8 Flying System Safety reminder Two female keyhole stud plates...

Page 64: ...lly arrayed for wide coverage 30 left right clusters will be mirror image High mid high horizontal coverage would be 1 2 left W8CT 30 30 1 2 right W8CT one W8CT 30 30 55 60 115 30 30 30 30 30 30 30 Al...

Page 65: ...audience is expected forward of the mix position 15 Reminder Splay angles are always quoted axis to axis not between cabinet sides ie 30 0 30 0 As with W8Cs the single box horizontal coverage is 55 H...

Page 66: ...kept small to avoid vertical coverage gaps 15 8 20 Note that the Longthrow system s output is considerably greater than the Compact s for the same input voltage so some level tailoring tends to be re...

Page 67: ...ts Note that when just a few Wavefront Longthrow elements are used to supplement a large W8C system high mid high W8CTs may be used without low mid W8CMs as low mid energy is provided by adjacent W8C...

Page 68: ...otice the gradual 6dB increase in high frequency at the back of the field 3dB at the mix position until the guest engineer arrives having walked the field with a clean pair of ears and wants to change...

Page 69: ...ide winds Gusting side winds can dramatically effect mid and high frequency sound by changing the propagation direction and therefore the way adjacent radiators interact as follows Single sound source...

Page 70: ...sensitive interferometer Martin Audio Wavefront Longthrow horns are stacked vertically and adjacent W8CTs may be flown in mirror image and splayed 30 40 for coherent arraying to minimise high frequenc...

Page 71: ...l wavefront will be slowed less near the ground and its sound path will veer upwards Conversely a wind gradient associated with wind blowing from behind a loudspeaker system will speed up its vertical...

Page 72: ...ol the air at night causing it to flow down hill to form a katabatic wind To maintain coverage loudspeaker cluster tilts may need to be readjusted between morning orchestral rehearsals for a major out...

Page 73: ...and several times stronger than the main wind Their effects will be far more audible than a steady wind Anti phasing eq It may be advisable to roll off the system s high frequency response during gust...

Page 74: ...will warm low level air and the atmosphere will heat up by convection from bottom to top Warm air cannot rise to the top of the atmosphere because air pressure drops with height and air temperature fa...

Page 75: ...effects Air absorption is quoted in dB m and occurs over and above the usual sound pressure level changes caused by an expanding wavefront quoted in dB doubling of distance Air absorption changes wit...

Page 76: ...rises but this is not always obvious in warmer weather as our ears produce more secretions when we perspire Note that even at high relative humidity we will still loose 10dB at 10KHz over 100m Martin...

Page 77: ...MARTIN AUDIO L O N D O N The Martin Experience Wavefront Compact Series Applications Guide Section 3 Wavefront W8CS Flown Subwoofer All material 2007 Martin Audio Ltd Subject to change without notice...

Page 78: ...tions 3 3 Pin outs and cabling 3 4 System patching 3 5 DX1 Loudspeaker Management System 3 6 Power amplifier recommendations 3 6 1 Martin Audio MA4 2 Power Amplifier Overview 3 7 Adding W8CS to flown...

Page 79: ...rs up to120Hz or may be flown as mid bass sections 60 160Hz to complement floor standing WSXs Like all flown Wavefront products W8CS are fitted with MAN load certified flying points and are designed t...

Page 80: ...teel Grille finish Grey paint Dimensions inc wheels W 562mm x H 799mm x D 925mm W 22 1ins x H 31 5ins x D 36 4ins Flown weight 61kg 134lb Lid 4kg 9lb extra Before rigging note colour coding W8C has 2...

Page 81: ...8MPR 8 pole panel male NL8MM 8 pole inline coupler male male Connectors should be kept in good clean uncorroded condition to ensure full undistorted loudspeaker performance Corroded or damaged pins an...

Page 82: ...e sub mix for bass mid bass sections This is good practice as it helps provide main system headroom for those all important vocals and solos whilst allowing for larger than life percussion and bass in...

Page 83: ...drive system noise floors inaudible and avoiding amplifier slew rate limiting W8CS assuming 800Wcont 1600Wpk into 8 power amplifiers Best fit Initial DX1 Amplifier Amplifier Amplifier Output GAIN Exa...

Page 84: ...cursions that stress and age drivers The best way to get the clean relaxed sound of an overpowered amplifier is to choose an amplifier with plenty of current reserve ie an amplifier with good 2 specif...

Page 85: ...st 8001 x40 8 1 95 32 7 Crest 9001 x40 8 1 95 32 7 QSC PL236A 32dB 8 1 95 32 7 9 2 18 31 8 10 2 45 30 9 11 2 75 29 10 12 3 08 28 11 13 3 46 27 12 Crown MA3600VZ 26dB 14 3 88 26 13 Crown MA5002VZ 26dB...

Page 86: ...ifiers to provide outputs 1 5 2 times their quoted power for short term bursts Martin Audio products will withstand this potential doubling of instantaneous power with suitably set controller limiters...

Page 87: ...lly better to use the appropriate amplifier in 2 channel mode than to use an inadequate amplifier in bridged mode Power amplifier gain or level settings reminder Gain switches If you are lucky enough...

Page 88: ...orts are recommended Check the manufacturer s application notes for details 3 6 1 Martin Audio MA4 2 Overview Features Switch mode power supply Superior sonic performance Light weight Advanced protect...

Page 89: ...computers and televisions However the demands of high power audio are very different to these applications The MA4 2 overcomes the size and weight constraints of conventional power supplies whilst at...

Page 90: ...afe temperature by muting the input signal when the internal temperature rises above 90 C Short Circuit Protection The MA4 2 amplifier is completely short circuit protected The protection circuits per...

Page 91: ...nd 7kHz at 500W 4 ohms 0 1 4 ohms 0 04 4 ohms 0 04 4 ohms 0 04 4 ohms 0 04 Power Matrix LOAD CONFIGURATION 16 ohms Stereo 2 channel 8 ohms Stereo 2 channel 4 ohms Stereo 2 channel 2 ohms Stereo 2 chan...

Page 92: ...will absorb mid bass from low profile ground stacked subwoofers Flying W8CS as horn loaded mid bass complements the horn loaded WSX subwoofers to provide an incredibly tight efficient and detailed bas...

Page 93: ...ncreasing forward projection allowing high gain before feedback The following iconic layout may be used to represent the above cluster 30 20 20 20 20 20 20 20 20 Important reminder Splay angles are al...

Page 94: ...applications Note that flying W8CS in rows keeps clusters relatively narrow where width is at a premium Coverage would be 145 horizontal x 70 vertical For very high power rock or dance applications t...

Page 95: ...hat half of the total system power is demanded between 60Hz 160Hz during heavy rock and dance music W8CS flown in columns with W8Cs 15 20 20 20 20 20 20 20 Again coverage would be 145 Horizontal x 70...

Page 96: ...quired for TV cameras or may be configured as flown mid bass elements to complement floor stacked WSXs For further information on suitable Wavefront subwoofer systems and a brief tutorial on bass stac...

Page 97: ...RTIN AUDIO L O N D O N The Martin Experience Wavefront Compact Series Applications Guide Section 4 Wavefront WSX Folded Horn Subwoofer All material 2007 Martin Audio Ltd Subject to change without noti...

Page 98: ...3 Pin outs and cabling 4 4 System patching 4 5 DX1 Loudspeaker Management System 4 6 Power amplifier recommendations 4 7 Placement 4 8 WSX application examples 4 9 Further examples 4 10 Spaced systems...

Page 99: ...ns Freq response 38 150Hz 3dB half space LF limit 10dB 28Hz Rated Power 600W into 8 ohms 2400W peak Sensitivity 105dB half space with band limited pink noise Maximum SPL 132dB continuous 138dB peak ha...

Page 100: ...in outs and cabling WSX NL8 WSX 1 Driver 1 Driver 2 Driver 2 Driver 3 n c 3 n c 4 n c 4 n c See Section 1 3 for connector pin out drawing All material 2007 Martin Audio Ltd Subject to change without n...

Page 101: ...able run vs copper core cross sectional area Single WSX Two WSXs paralleled Up to 50m 2 5mm 6mm or 2 x 2 5mm cores in parallel Up to 100m 6mm 10mm or 2 x 6mm cores in parallel Q Why the odd sizes A Lo...

Page 102: ...r and correctly set up controller preferably the Martin Audio DX1 will provide the most dynamic system performance and protection whilst simplifying design and reducing spares inventories The Martin A...

Page 103: ...4 2 rear MLS switch to 0dB to match peak output of unregulated power amplifiers Limiter settings The Rated Power specification in Section 4 2 indicates the maximum long term power dissipation that can...

Page 104: ...minimise amplifier clipping for high quality trouble free operation WSX assuming 600 W into 8 power amplifiers Best fit Recommended Amplifier Amplifier Amplifier DX1 LIMITER Example Sensitivity Gain...

Page 105: ...amplifier output specifications Most power amplifier manufacturers keep their costs down by using unregulated supply rails which sag under load To allow for this sag manufacturers set their rails hig...

Page 106: ...m load An electrical technician should check the mains supply vs demand using an accurate rms voltage meter 2 If unfamiliar generators are being used the electrical technician should check the mains w...

Page 107: ...for loudspeaker sections requiring the strongest drive Other amplifiers driving apron subwoofer sections for instance may be backed off as required for smooth coverage This process will ensure that th...

Page 108: ...umns show a slight improvement in mid bass amplitude and polar response but the effect becomes insignificant in large flat fronted arrays or widely spaced stage apron systems 2 wide symmetrical column...

Page 109: ...that there are no coverage nulls within the forward 180 at mid bass crossover frequencies Wide coverage arrays have significant output beyond 180 making them more prone to room colouration Narrow mea...

Page 110: ...Varies with temperature see Section 2a Arcsin means the angle whose sin is Flat fronted cluster coverage patterns will be confined to one main lobe whose mid bass crossover directivity is proportiona...

Page 111: ...ing in sound pressure level terms but is not suitable for superimposing a polar plot onto a venue plan Venue plans are drawn to a linear scale so polar plots with linear amplitude scales would be more...

Page 112: ...l at a distance of 50m and 34m above floor level at 100m It is possible to reach higher seating areas whilst retaining the long throw characteristics of a tall vertical stack by electronically tilting...

Page 113: ...or short wide shots Horizontal Boundary effects A solid wall near an array will act as a reflector This will cause a horizontal array to perform as if it were twice as wide giving a useful low frequen...

Page 114: ...cause off axis irregularities combing because time offsets start to become significant See Section 4 10 for a more detailed explanation An odd number of half wavelengths will cause nulls along the lin...

Page 115: ...m 38 160Hz 0 5m 38 115Hz 1 0m 38 86Hz 2 0m 38 60Hz To avoid combing Keep horizontal gaps below 1m for upright WSXs Keeps horizontal gaps below 0 2m for horizontal WSXs 4 7 4 Horizontal splays Splaying...

Page 116: ...y cause low frequency build up on thrust and island stages Avoid this problem by augmenting small stage corner systems with WSXs placed along the stage apron For a smooth polar crossover Array the WSX...

Page 117: ...desirable to excite the natural room acoustic for this type of application 2 WSX set up for small very high power dance rock production Gives very narrow vertical wide horizontal coverage up to 120Hz...

Page 118: ...WSX arrays for tight horizontal control and the more tightly packed apron systems for central focusing 4 WSX set up for very high power dance rock production in wide arena Gives wide horizontal very n...

Page 119: ...l cases 1 Set the main L R WSX stacks to match the main L R system farfield levels around 120Hz fine tuning system delays as required 2 Set the L R stack front fills to balance the main L R systems WS...

Page 120: ...r system farfield levels around 120Hz 2 Set the front rear W8Cs to balance the main systems WSXs in the nearfield 3 Set the flown centre W8Cs to balance the main systems WSXs W8Cs in the L R centre mi...

Page 121: ...t rear corner system farfield levels around 120Hz 2 Set the front rear W8Cs to balance the main systems WSXs in the nearfield 3 Set the flown centre W8Cs to balance the main systems WSXs W8Cs in the L...

Page 122: ...e instant shown but the extra distance travelled by the second R signal causes it to be out of phase at the listener position at that particular frequency R is ve while L is ve Reflections Remember th...

Page 123: ...shows how two pairs of sine waves with identical amplitude and frequency characteristics will sum Pair a are in phase and add Pair b are out of phase and cancel All material 2007 Martin Audio Ltd Sub...

Page 124: ...100Hz The polar plot shows the far field polar response of the two subwoofers when driven in phase with the same 100Hz signal Subwoofer interaction causes irregular coverage either side of the centre...

Page 125: ...tring cello double bass sections or for unplugged performances 60Hz At 60Hz the spacing is an odd number of half wavelengths again so we see side nulls again 40Hz When the frequency drops to 40Hz the...

Page 126: ...er coverage at that frequency but the spacing could still give coverage irregularities at mid bass frequencies due to the shorter wavelengths at higher frequencies The real world Bass notes usually in...

Page 127: ...effects In practice these peaks and troughs can be smoothed out with additional fill systems 4 11 Electronic steering It is possible to aim ground stacks towards distant raked seating or balconies or...

Page 128: ...subwoofer stack to the highest most distant seats using an inclinometer and to calculate the required delay increment with the formula shown Example We wish to project bass mid bass punch to stadium...

Page 129: ...to horizontal arrays For instance it is common to use curved main clusters for smooth mid and high frequency coverage Ground based subwoofer arrays should follow the same curvature to maintain mid ba...

Page 130: ...All material 2007 Martin Audio Ltd Subject to change without notice...

Page 131: ...004 Copyright by Martin Audio Ltd 2004 all rights reserved Martin Audio Ltd Century Point Halifax Road Cressex Business Park High Wycombe Buckinghamshire UK The information presented in this document...

Page 132: ...M 3 way mini line array The W8L and W8LC systems are fully horn loaded tri amplified systems All sections are 8 ohms for easy paralleling in pairs The W8LM system combines direct radiating and horn lo...

Page 133: ...ced point source drivers W8L Midrange section Wavefront W8L Series line arrays feature integral quick deployment flyware systems which allow progressive curvature columns of up to 16 cabinets to be as...

Page 134: ...fessional riggers or trained personnel under professional riggers supervision Flying professional loudspeaker systems is not a job for amateurs See the appropriate Flying System User Manual for furthe...

Page 135: ...n loaded cone drivers HF 3 x 1 horn loaded compression drivers LF MF 2 x 8 cone drivers 1 ported direct radiating LF 1 Hybridtm horn loaded LF MF HF 2 x 1 horn loaded compression drivers Rated Power L...

Page 136: ...L8 or PAcon sockets Input Link 2 x Neutrik NL4 sockets Input Link Enclosure Vertical trapezoid 3 75 deg top bottom walls Multi laminate birch ply Vertical trapezoid 3 75 deg top bottom walls Multi lam...

Page 137: ...W8L W8LS outline dimensions W8L shown All material 2007 Martin Audio Ltd Subject to change without notice...

Page 138: ...W8LC outline dimensions All material 2007 Martin Audio Ltd Subject to change without notice...

Page 139: ...W8LM outline dimensions All material 2007 Martin Audio Ltd Subject to change without notice...

Page 140: ...W8LX outline dimensions All material 2007 Martin Audio Ltd Subject to change without notice...

Page 141: ...W8L polar plot W8L beamwidth plot All material 2007 Martin Audio Ltd Subject to change without notice...

Page 142: ...W8LC polar plot W8LC beamwidth plot All material 2007 Martin Audio Ltd Subject to change without notice...

Page 143: ...W8LM polar plot W8LM beamwidth plot All material 2007 Martin Audio Ltd Subject to change without notice...

Page 144: ...d of its molecules Molecules of different weight other gases maybe or different velocity that translates into temperature will exhibit different speeds of sound Motion of the sound source the listener...

Page 145: ...ndard inverse square law for point sources For a point source it represents a 6dB reduction in sound pressure level per doubling of distance If the ground is quite hard and reflective compensation mus...

Page 146: ...te integral Considering this it is easy to imagine that at a very great distance or very small size both sources will ultimately approximate an ideal point source This suggests that for such sources t...

Page 147: ...ree tightly arrayed low curvature horns at 8kHz Vertically spaced wide coverage horns will have hot spots directly in front of each horn and will comb add or subtract depending on the wavelength and r...

Page 148: ...All material 2007 Martin Audio Ltd Subject to change without notice...

Page 149: ...n designed with this in mind The W8L Series are deliberately designed to produce slightly curved vertical wavefronts enough to allow up to 7 5 of vertical splay to be introduced between boxes but not...

Page 150: ...ummation point near the top of a progressively curved array and aims this towards the furthest listening area A progressive curvature array s HF coverage weakens dramatically above the maximum summati...

Page 151: ...cannot be reduced simply because the band is a quiet traditional folk combo A short line array column would project only mid frequencies to the far field It would lack warmth and sparkle as it would...

Page 152: ...projection out far enough for mid high air absorption to have a balancing effect The following curves show the spectral balance of 4 and 12 W8L cabinets vs distance taking air absorption into account...

Page 153: ...t is based on applications experience and line array physics as it is currently understood Quantity W8L no subs W8LC no subs W8LM no subs Cabinets arrayed with 2 or less inter cabinet splay Throw in m...

Page 154: ...x W8L at 1 per side festival system in side wings for 100m throw Example 2 16 x W8L per side arena system Upper 12 cabinets at 1 2 for 100m throw All material 2007 Martin Audio Ltd Subject to change w...

Page 155: ...Example 3 12 x W8LM per side 41m concert hall system All material 2007 Martin Audio Ltd Subject to change without notice...

Page 156: ...ar field projection increasing towards the bottom 0 straight arrays are calculated for up to 16 cabinets as curvature losses are not applicable See look up table below B Radial attenuation is the redu...

Page 157: ...W8LC or 16xW8M 6m array 12xW8L or 16xW8LC 8m array 16xW8L 16m 15dB 12dB 12dB 12dB 12dB 32m 21dB 15dB 15dB 15dB 15dB 64m 27dB 21dB 18dB 18dB 18dB 128m 33dB 27dB 21dB 21dB 21dB 256m 39dB 33dB 27dB 24dB...

Page 158: ...5 5 ViewPointtm Version 3 03 Contents 5 5 1 Introduction 5 5 2 Installing ViewPointtm 5 5 3 Using ViewPointtm 5 5 4 Entering venue data 5 5 5 Coverage start and stop 5 5 6 Array type 5 5 7 Array fixi...

Page 159: ...ch and one of the controller preset indicated for accurate Band Zoning and smooth coverage 1 The controller preset names shown on ViewPointtm correspond to the preset names on our DX1 XTA DP226 or XTA...

Page 160: ...ll indicate splay angles and controller presets for these flown systems W8L Full range line array W8LS Sub woofer W8LC Compact line array W8LM Mini line array WLX Sub woofer and these flown combinatio...

Page 161: ...rogramme It indicates optimum line array curvature based on simple audience dimensions that may be gathered from basic venue drawings or from a quick on site survey For best results planes should be u...

Page 162: ...1 height can be negative or positive For planes two and three Elev refers to the elevation height of the front of the plane For plane three Distance relates to the actual distance from the front of th...

Page 163: ...se to calculate angles from X and Y data 5 5 4 3 Single Point Survey This option enables you to enter all plane data from a single reference point directly under the intended flying point or above the...

Page 164: ...orm of venue dimension You can switch back and forth between the single point survey and direct form at any time 5 5 5 Coverage start and stop Specify the horizontal coverage distances from the front...

Page 165: ...s 5 5 7 Array Fixing Select either Fly or Stack in the Fixing section to determines how the array is supported In Fly mode the grid is suspended and cabinets are attached beneath In Stack mode the gri...

Page 166: ...ug and the relevant motor hook to ensure that motor chain bags do not rest on the grid or top cabinet and upset its tilt angle Array Height Set the array height for best coverage It refers to the high...

Page 167: ...rray too high and therefore too curved for efficient cabinet to cabinet summation Array view inefficient design Array too curved for efficient cabinet to cabinet summation All material 2007 Martin Aud...

Page 168: ...design Lower curvature for efficient cabinet to cabinet summation Array view efficient design Lower curvature for efficient cabinet to cabinet summation All material 2007 Martin Audio Ltd Subject to c...

Page 169: ...ill appear VERY IMPORTANT NOTE Long throw applications will require arrays long enough to ensure the appropriate vector summation for the distance to be covered Too few cabinets may result in an inapp...

Page 170: ...Venue name Enter the name of the venue Previously saved venue names will appear here 5 5 11 Editing ViewPointtm designs Once the initial venue and array parameters have been entered and the Design but...

Page 171: ...tions and overspill ViewPointtm s auto calculation routine is based on a combination of theoretical modeling and practical experience and aims to give the most consistent frequency response over the a...

Page 172: ...ought of as the vector sum of all the cabinets 7 5 degrees from that point not simply due to the cabinet whose ray is aiming there The example above shows that the cabinet 7 area receives contribution...

Page 173: ...you Enter the number of WLXs you wish to use in the number box to the right of the Match WLX button then click the Match WLX button A WLX array is generated that has a similar shape to your original...

Page 174: ...osition the cross hair over the dark blue squares at the end of each ray until the box turns red 2 Use the left and right mouse buttons to increase or decrease the array tilt top cabinet only or inter...

Page 175: ...face It is not advisable to miss the surface completely as temperature gradients in the air can steer high frequencies upwards or downwards by 5 or more from the direction the cabinets are pointing in...

Page 176: ...This is shown by the blue vertical line on the Array view which indicates the datum point from which coverage Start Stop distances are measured Pick Points and Cabinet Positions Two grid pick points f...

Page 177: ...le for W8LC WLX and W8LM flown arrays When Lifting Bar is selected further options become available The lifting bar can be placed in the Rear or Front position and can be lifted at either one or two p...

Page 178: ...ack make sure that the lifting bar is in the rear position and that the cabinet is mounted at the front of the grid before trying an alternative height Similarly if the required lifting point is too f...

Page 179: ...ging points Allow fine angular control using the motors Load Indicators Depending on the grid configuration the Rear Pick Load and Front Pick Load are displayed as well as total mass These loads as we...

Page 180: ...ired to push or pull the array over is less than that shown in the box beside the array view and a mechanical warning is raised Please note This assumes that no sliding takes place Grids should be sec...

Page 181: ...ains distribution Move your mouse cursor over the greyed out amplifier racks to see further rack details Historically array cabinets have been numbered from top to bottom see Quick Start sections W8L...

Page 182: ...lets to the top to bottom cabinet numbering Note that W8Ls and W8LCs are driven in pairs whereas W8LMs are driven in fours Speaker Outlet Cabinet number W8L W8LC W8LM pairs fours H 1 2 G 3 4 F 5 6 E 7...

Page 183: ...eric effects and personal taste A reminder ViewPointtm produces sonically accurate results based on high resolution loudspeaker data and the audience coverage You must use the exact reference preset a...

Page 184: ...1 6 Power amplifier recommendations A1 6 1 Martin Audio MA2 8 Power Amplifier Overview A1 7 General operational summary A1 8 Arraying and placement A1 9 Coverage calculations A1 10 W8 front fills A1 1...

Page 185: ...with MAN load certified flying points and are designed to comply with the 12 1 safety factor specified by the German VBG70 standard when used with compatible 12 1 flying systems One important advantag...

Page 186: ...mid 16 ohms nominal High 16 ohms nominal Coverage 6dB 55 horizontal 30 vertical Crossover 750Hz 3 5kHz Connectors 2 x Neutrik NL8 2 x EP8 Cabinet construction Birch Ply Cabinet finish Slate textured...

Page 187: ...1 Low Mid Low Mid 2 1 Low Mid Low Mid 3 2 High Mid High Mid High 4 2 High Mid High Mid High 5 3 High n c 6 3 High n c 7 4 n c n c 8 4 n c n c see Section A1 5 for details of the connector panel Active...

Page 188: ...ommended loudspeaker cable Cable run vs copper core cross sectional area Single W8 Two W8 paralleled at the cluster Up to 50m 2 5mm 6mm or 2 x 2 5mm cores in parallel Up to 100m 6mm 10mm or 2 x 6mm co...

Page 189: ...systems may be assembled using the same two DX1 units but with extra slave amplifiers and loudspeakers See Section A1 5 for further DX1 information A1 4 1 Cluster sub sections When designing a large...

Page 190: ...ed from just a Martin Audio DX1 controller set up for 3 way operation See Section A1 5 for further DX1 information Power amplifier channel allocations There are 8 pairs of W8 loudspeakers each requiri...

Page 191: ...Midfield inner outer high Midfield inner outer himid Midfield inner outer lomid Nearfield inner outer high Nearfield inner outer himid Nearfield inner outer lomid Downfill inner outer high Downfill i...

Page 192: ...evel settings Initial inner level settings can be calculated for each row as follows The farfield inner power amplifier channels are the reference All material 2007 Martin Audio Ltd Subject to change...

Page 193: ...e the following amplifier channel settings The attenuation rate shown here is 2dB per cluster row The actual rate of vertical attenuation will depend on the cluster height which in turn will depend on...

Page 194: ...rtical layout is In a narrower venue we may require the outer sections to be attenuated a little particularly in the farfield section as follows All material 2007 Martin Audio Ltd Subject to change wi...

Page 195: ...tions and power amplifiers DX1 Factory Preset Examples W8 Rear panel Active Passive switch Please note that the W8 rear connector panel is equipped with an Active Passive switch Active mode DX1 factor...

Page 196: ...8s driven in pairs The following shows the DX1 with programme 20 selected This caters for a stereo set up comprising left and right W8s in Passive mode plus separate left and right WSX folded horn sub...

Page 197: ...20kHz 1 36 octave steps 368 positions Filter Q BW 0 4 to 128 2 5 to 0 008 Sections switched to shelving response Low frequency 20Hz 1kHz High frequency 1kHz 20kHz Shelf gains 15dB in 0 1dB steps Cros...

Page 198: ...87 35 6 6 4 QSC PL224 2 0 98 34 5 5 3 3 1 09 33 4 4 2 Martin MA2 8 32dB 4 1 23 32 3 3 1 Crest 4801 x40 4 1 23 32 3 3 1 Crown K1 1 4v 4 1 23 32 3 3 1 QSC PL218 218A 32dB 4 1 23 32 3 3 1 QSC PL224A 32dB...

Page 199: ...nal operator error over powered or bridged amplifiers can cause over excursions that stress and age drivers The best way to get the clean relaxed sound of an overpowered amplifier is to choose an ampl...

Page 200: ...4 1 23 32 3 0 3 Crown K1 1 4v 4 1 23 32 3 0 3 QSC PL218 218A 32dB 4 1 23 32 3 0 3 QSC PL224A 32dB 4 1 23 32 3 0 3 Crown MA1202 1 4v 5 1 38 31 4 1 2 6 1 55 30 5 2 1 7 1 73 29 6 3 0 8 1 95 28 7 4 1 9 2...

Page 201: ...components due to excessive signal density Amplifiers with excessive output may damage voice coils or age driver suspensions due to excessive heat dissipation and excursion A note about power amplifi...

Page 202: ...tem is patched Power reserve Power amplifier specifications are usually based on bench measurements made using stable high current mains supplies and well defined loads Amplifiers sound best when they...

Page 203: ...r level control advanced in sequence to check system operation and patching Assuming that controller output levels and limiters have been set as tabulated in Section A1 5 2 power amplifier level contr...

Page 204: ...e operating temperatures of each output device In contrast a conventional tunnel design can result in a temperature variance of up to 40 between output devices Switch Mode Power Supply The MA2 8 s swi...

Page 205: ...e the input signal proportionally Thermal Protection Thermal Protection circuitry prevents the amplifier from running at an unsafe temperature by muting the input signal when the internal temperature...

Page 206: ...Hz at 500W 4 ohms 0 08 4 ohms 0 03 4 ohms 0 02 4 ohms 0 03 4 ohms 0 08 Power Matrix LOAD CONFIGURATION 16 ohms Stereo 2 channel 8 ohms Stereo 2 channel 4 ohms Stereo 2 channel 2 ohms Stereo 2 channel...

Page 207: ...e calibrate its output levels controls to their 0dB nominal position initially These settings will be easier to get back to and will avoid embarrassing level setting mistakes during the show particula...

Page 208: ...cenery movements etc Wide coverage broadband stack Although a single Wavefront W8 s horizontal coverage is 55 at high frequencies the system has been designed to integrate well with smaller splays for...

Page 209: ...y chained D rings using keyhole cabinet fittings hence the tendency to base flown designs in this applications guide on multiple columns The beauty of the MAN system is that each cabinet in a system s...

Page 210: ...e vertical coverage of a W8 cluster can be calculated as follows Vertical coverage of a W8 the vertical coverage of a single W8 30 the sum of all the vertical splay angles For a 3 deep W8 cluster with...

Page 211: ...ll the vertical splay angles For a 4 deep W8 cluster with 20 vertical splay angles 30 20 20 20 90 Horizontal coverage of a W8 cluster the horizontal coverage of a single W8 55 the sum of all the horiz...

Page 212: ...55 30 30 30 30 30 205 for 30 horizontal splays and the vertical coverage extends to 30 20 20 20 90 for 20 vertical splays Circular cluster Two 6 wide 4 deep W8 clusters with 30 horizontal splay angle...

Page 213: ...age allows foldback to be provided to the ice dancers The centre hole may be filled by flying a smaller cabinet underneath the main cluster Circular 4 deep W8 cluster All material 2007 Martin Audio Lt...

Page 214: ...ain PA downfills these apron fills don t just balance the subwoofers They can focus vocals and add a detailed quality that can be beneficial right out to the mix position If the apron fill loudpeaker...

Page 215: ...typically across a wide cycle track so fairly powerful side clusters may be required for good projection and intelligibility W8s blend in sonically without off axis lobing and stage mic colouration D...

Page 216: ...considered for panning spot effects around the venue Flown radial delays Flown distribution or delay loudspeakers should be placed on radii converging at the stage and staggered for smooth coverage D...

Page 217: ...ions will affect placement for heavily raked seating areas and intelligent compromises will need to be made Delay systems should be thoroughly checked over a wide listening area to ensure that their l...

Page 218: ...t to scale Small delay time errors are inevitable where delay towers are located in audience areas eg on a football field due to the three dimensional geometry involved Controller delays should be adj...

Page 219: ...to combine Wavefront 8 components using the correct crossover characteristics and delay settings Experienced users may mix and match DX1s with standard crossover settings for custom combinations See t...

Page 220: ...r 2 rows of W8CTs being used to augment the outer columns The W8 to W8CT vertical splay angle is kept very small 3 just one M A N flying system chain link to provide a smooth transition between the tw...

Page 221: ...See Section 2 for further Wavefront W8CT CM information See Section A2 for guidance on W8 W8S combinations All material 2007 Martin Audio Ltd Subject to change without notice...

Page 222: ...in outs and cabling A2 4 System patching A2 5 DX1 Loudspeaker Management System A2 6 Power amplifier recommendations A2 6 1 Martin Audio MA4 2 Power Amplifier Overview A2 7 Adding W8S to flown W8 syst...

Page 223: ...performance to below 40Hz Like all flown Wavefront products the W8S is fitted with MAN load certified flying points and is designed to comply with the 12 1 safety factor specified by the German VBG70...

Page 224: ...r Connectors 2 x Neutrik NL8 2 x EP8 Cabinet construction Birch Ply Cabinet finish Slate textured paint Protective grille Perforated steel Grille finish Grey paint Dimensions inc wheels W 562mm x H 10...

Page 225: ...up cables and patch panels Neutrik NL connectors NL8FC 8 pole cable female NL8MPR 8 pole panel male NL8MM 8 pole inline coupler male male Cannon EP connectors EP8 11 8 pin cable female EP8 12 8 pin ca...

Page 226: ...tching suggestions and examples Bass sub mix operation Many mix operators prefer to create a separate sub mix for bass mid bass sections This is good practice as it helps provide main system headroom...

Page 227: ...r amplifiers Best fit Initial DX1 Amplifier Amplifier Amplifier Output GAIN Example Sensitivity Gain Lo15 Lo18 o ps dBu Vrms dB dB Crown MA5002VZ 0 775v 2 0 62 42 9 Martin MA4 2 41dB 1 0 69 41 8 Crest...

Page 228: ...rating unless the amplifier s power rails are well regulated see Section A2 6 even with properly set controllers in place Although Martin Audio drivers are mechanically designed to survive normal roa...

Page 229: ...x115 1 0 69 41 2 Crown MA3600VZ 0 775v 1 0 69 41 2 0 0 77 40 1 1 0 87 39 0 2 0 98 38 1 3 1 09 37 2 QSC PL236 PL236A 36dB 4 1 23 36 3 5 1 38 35 4 6 1 55 34 5 7 1 73 33 6 Martin MA4 2 32dB 8 1 95 32 7 C...

Page 230: ...keep their costs down by using unregulated supply rails which sag under load To allow for this sag manufacturers set their rails high so that they still meet their quoted output into specified loads...

Page 231: ...crawling with spikes or interference 3 Avoid driving too many W8S drivers in parallel I would suggest no more than 2 x 15 or 2 x 18 per amplifier channel so that the power amplifier s 2 ohm spec is k...

Page 232: ...rols should be set to full fully clockwise for loudspeaker sections requiring the strongest drive Amplifiers driving nearer field section within the same cluster may be backed off as required for smoo...

Page 233: ...plifier and exhaust from the rear A horizontal pressure chamber between the heatsink and the cooling fans ensures that there is little difference in the operating temperatures of each output device In...

Page 234: ...are independent and inaudible in normal use Clip Limiters Clip limiters prevent dangerous clipped signals reaching the speaker They work by monitoring the output to check for signals not present at th...

Page 235: ...ture Turn on VHF Over and under voltage Clip limiters AFS Short circuit Distortion THD 20Hz 20kHz and 1W 1000W THD at 1 kHz and 2000W DIM 30 at 500W CCIF 13 and 14kHz at 500W SMPTE 60Hz and 7kHz at 50...

Page 236: ...ll absorb mid bass from low profile ground stacked subwoofers Flying W8S will provide a tight efficient and detailed bass performance without audience mid bass absorption A2 7 1 W8S W8 configurations...

Page 237: ...conic layout may be used to represent the above cluster Important reminder Splay angles are always quoted axis to axis not between cabinet sides ie All material 2007 Martin Audio Ltd Subject to change...

Page 238: ...equency headroom for higher power rock dance club applications Flying W8S in rows keeps clusters relatively narrow where width is at a premium Coverage would be 145 horizontal x 70 vertical All materi...

Page 239: ...4 for further information on WSX folded horn subwoofers Power amplifier monitoring at real world gigs have shown that half of the total system power is demanded between 60Hz 160Hz during heavy rock an...

Page 240: ...r the ground s boundary effects are required to maximise system headroom Stacking safety Stacked W8S should always be blocked strapped and anchored from above by a qualified rigger Coverage angle for...

Page 241: ...luster coverage patterns will be confined to one main lobe whose mid bass crossover directivity is proportional to the size of the cluster The medium sized array left has significant output to 90 wher...

Page 242: ...t onto a venue plan Venue plans are drawn to a linear scale so polar plots with linear amplitude scales would be more suitable iii Polar plots have been simplified in this article for clarity Real wor...

Page 243: ...de 69 8 Wide 69 33 16 69 33 16 With W8S standing upright flat fronted cluster coverage patterns will be confined to one main lobe whose mid bass crossover width is inversely proportional to the size o...

Page 244: ...fewer units but care must be taken to avoid irregular coverage at higher mid bass frequencies The following formula gives the pressure ratio wrt the on axis pressure for any off axis angle of a regul...

Page 245: ...example above An even number of half wavelengths will cause lobes along the line of the loudspeakers see the 2 wavelength example below The following tables give the maximum recommended gap between W...

Page 246: ...upright with the 18 unit at the bottom This ensures that the side rigging points are nearest the top for safe rigging Straps and rigging systems should be used to prevent ground stacks from falling o...

Page 247: ...This practice improves low frequency consistency particularly at and around the typical central auditorium mix position Note that W8S subwoofers may be used with other members of the Wavefront family...

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