Manuale d’uso / di manutenzione del prodotto WLX del fabbricante Martin Audio
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The Martin Experience WLX, WLXGS User ’s Guide PREMININARY INFORMA TION All material © 2007. Martin Audio Ltd. Subject to change without notice..
Wavefront WLX and WLXGS Hybrid™ Subwoofer Preliminary information Introduction The powerful WLX Hybrid™ subwoofer is designed to complem ent Wavefront W8L Series tou ring systems to provide deep bass with maximum efficiency. WLX Rigging options Standard WLX subwoofers are equipped with integral flying hardware.
A combined WLX/W8LM grid (ASF20003 – not shown) ha s been designed to enab le W8LM miniature line array elements to be flown ben eath standard WLX subwoofers. Rear connector brackets (ASF20005) are also available for flying W8LC compact line arrays below WLX subwoofers.
Pin-outs and cabling WLX Input N L 8 W L X -1 Driver – (& link -1) +1 Driver + (& link +1) -2 Driver – (& link -2) +2 Driver + (& link +2) - 3 l i n k - 3 + 3 l i n k + 3 - 4 l i n k - 4 + 4 l i n k + 4 All material © 2007. Martin Audio Ltd.
Cable and panel connector part numbers Please note the following part numbers when orderi ng loudspeaker connectors to m ake up cables and patch panels Neutrik NL connectors NL8FC 8 pole cable (female.
Sub-woofer crossover and alignment Crossover frequencies The original factory controller se ttings for W8L, W8LC and W8LM sy stems are intended for use with sub- bass systems such as the W8LS, WLX or W SX.
W8LM presets include the WLX sub-woofer so they ha ve two (mono) or four (stereo) unlocked delays. The WLX channel defaults to zero because the WLX has the longest horn. The W 8LM LF/Full-range and HF reference delays default to 3.931mS and 3.829mS respectivel y to time align the W 8LM to the WLX when the grilles are aligned.
Main to sub-woofer delays Reference settings The following table shows system delays to align various combinations of W 8L Series main and sub-woofer system. These should be treated as im portant initial settings and will work without further adjustments where grilles are alignm ent.
In all cases, set the main (W 8L, W8 LC or W8LM) and sub-woofer contro ller output parameters as follows, making sure that controller inpu ts are initiall y set flat (no equalisatio n), 0dB gain, 0ms delay.
4 x WLX + 8 x W8LC mixed array fo r orchestral applications using Connector Brackets – ViewPoint™ Rigging View Stacked WLXs or WLXGSs WLX or WLXGS subwoofers may be ground stacked be low the m ain system.
Stacked system alignment A stacked subwoofer system should be placed di rectly be neath the main system with the subwoofer and m ain system grilles vertically aligned. Subwoofer grilles and main sy stem grilles should be closely aligned so that they are at equal distances from a central audience area – preferab ly a well positioned mix position.
WLX sub-woofers may be time aligned without test gear as follows: 1) Start with t he controller out puts delays se t as per th e above t able 2) Use a laser tape mea sure to measure the distance to th.
overpowered models - with suitably set controller limiters - without risking uncontrolled power bursts. The MA series power amplifiers’ regula ted power rails also ensure maximu m performance under the real-world concert conditions of less-than-optimum ma ins supplies and low impedance loads.
have been checked and controllers have been set to suit the power amplifiers to be used. Music should be used to check that controllers are receiving and sendi ng the ap propriate signal bands and then each power amplifier level control advanced in sequen ce to check system operation and patching.
Symmetrically coupled 2-wide columns show a sli ght im provement in mid-bass am plitude and polar response - but the effect becomes insignifican t in large, flat fronted arrays or widely spaced stage apron systems. 2-wide symmetrical columns of WL X/WLXGS m ay be horizontally arrayed to improve mid-bass coverage.
Array Approx Boost Horizontal Vertical ( w r t s i n g l e u n i t ) coverage coverage - Wide Wide +12dB Wide Narrow +12dB Narrow W ide +24dB Narrow Narrow In these examples “wide” means th at there are no coverage nulls w ithin the forward 180º at m id-bass crossover frequencies.
Coverage angle for tightly packed flat fronted arrays -6dB Coverage Here is a simplified formula for calculating the m ain c overage angle of a tightly packed flat fronted array. * = approximate speed of sound in m/s. Va ries with temperature (see Section 2a).
The medium sized array (left) has significant ou tput to ±90º wh ereas the large array’ s ±90º output is dramatically reduced. A note on coverage nulls It is useful to be able to calculate where.
For instance, an 8 high ground-based stack of WLX/WLXGS subwoofers will act like the top h alf of a 16 high stack. It is possible to reach higher seati ng areas whilst retaining a tall vertical stack by electronically “tilting” the system - see later.
Again, a flexible side wall may absorb sound at certain low frequencies. Boundaries should always be treated with caution. Spacing It is possible to space out W LX or WLXGS subwoofers to provide a larger frontal area with fewer units but care must be taken to avoid irregular c overage at higher, mi d-bass frequencies.
Far field polar patterns can be quite complicated - even for a simple pa ir of subwoofers driven in unison. Wide spacing will cause off axis irregularities (com bing) because time off sets start to become significant.
Horizontal splays Splaying WLX/WLXGS arrays horizontally will widen their mid-bass coverage. The following sketch shows an 8 wide x 3 high WLX/WL XGS array arranged in four symmetrical pairs for smooth mid-bass coverage.
Stacked WLX/WLXGS application examples The following sketches show how WLX/WLXGS arrays may be deployed for a wide range of productions and types of venue. All productions and venues present their own unique requirements and these examples are intended as a template or starti ng point for your own specific design.
(3) WLX/WLXGS set-up for very high power dance/rock production in narrow arena Gives narrow horizontal & vertical co verage up to 120Hz - allowing for ground effects. Example 3 shows a very high power da nce or rock set-up for a narrow “shoe box” venue.
(5) Alternative set-up for wide venues Splayed WLX/ WLXGS array s for wide horizontal coverage. Example 5 shows a set-up for a TV shoot in a similar wide venue where sight-lines are critical. Note the lower profile, splayed arrays. Thrust stages Examples 6 show a typical set-up for a larg e, thrust st age productions.
Island stages (not shown) Island stages are simply four-sided versions of exam ples 3 and 5 and should be aligned using the same process. Tutorial on spaced systems Whenever two or more loudspeaker sy.
Addition & Subtraction The above shows how two pairs of sine waves (with identical am plitude 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. Subject to change without notice.
Polar variations with frequency Whether particular frequency components add or subt ract in the far field will depend on the louds peaker system spacing, the angular offset of the listener with respect to th e centre line, and the wavelength. The following polar responses show what happens when subwoofers are placed 8.
These lobes could cause low freque ncy feedback problems on stage with the high microphone gains used for orchestral low string (cello, double bass) se ctions or for “unplugged” perform ances. 60Hz At 60Hz the spacing is an odd number of half-wav elengths again so we see side nulls again.
40 Hz reduced spacing The above shows what happens at 40Hz if we reduce the spacing between the subwoofers to 4.3m. We get better central coverage without 40Hz side lobe s - adequate for long, narrow “shoe-box” venues but wider coverage would be required for most arenas.
Listeners in the 60º zone will hear th e note at a reduced leve l and may be more aware of room reverberation because the direct-to-reverberation ratio would be poorer for that note. Other notes would give d ifferent effects. In practice, these peaks and troughs can be smoothed out with additional fill systems.
Note that it is important to keep th e subwoofers tightly packed to avoid polar anomolies caused by spacing. Procedure The normal procedure is to measure the angle from the t op of the vertical subwoofer stack to the highest/most distant seats (using an inclinometer) and to calculate the required delay increm en t with the formula shown.
The following delay line taps would be required for the above system: t0 = 0m s t1 = 0.83mS t2 = 1.66mS t3 = 2.49mS t4 = 3.32mS t5 = 4.15mS t6 = 4.98mS Going further It is possible to apply electronic sh aping to horizontal array s. For instance, it is common to use curved m ain clusters for smooth mid and high frequency coverage.
Un punto importante, dopo l’acquisto del dispositivo (o anche prima di acquisto) è quello di leggere il manuale. Dobbiamo farlo per diversi motivi semplici:
Se non hai ancora comprato il Martin Audio WLX è un buon momento per familiarizzare con i dati di base del prodotto. Prime consultare le pagine iniziali del manuale d’uso, che si trova al di sopra. Dovresti trovare lì i dati tecnici più importanti del Martin Audio WLX - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso Martin Audio WLX imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul Martin Audio WLX ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il Martin Audio WLX, ma non hai ancora letto il manuale d’uso, dovresti farlo per le ragioni sopra descritte. Saprai quindi se hai correttamente usato le funzioni disponibili, e se hai commesso errori che possono ridurre la durata di vita del Martin Audio WLX.
Tuttavia, uno dei ruoli più importanti per l’utente svolti dal manuale d’uso è quello di aiutare a risolvere i problemi con il Martin Audio WLX. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo Martin Audio WLX insieme con le istruzioni su come risolverli. Anche se non si riesci a risolvere il problema, il manuale d’uso ti mostrerà il percorso di ulteriori procedimenti – il contatto con il centro servizio clienti o il servizio più vicino.
