BSS
Implementing the first pro audio application of Precision Audio’s Whiseworks NTM crossover filters, BSS’ flagship loudspeaker management processor (LMP), the Omnidrive Compact Plus FDS-366T allows operators to push loudspeakers extremely close to their operating bandwidths without risk of over-excursion.

Developed by Neville Thiele, the crossover uses a notched response to achieve a very steep roll-off rate outside the pass-band. Similar to the industry standard Linkwitz-Riley crossover shape, it eliminates phase difference between adjacent bands throughout the crossover region, preventing polar pattern shift as frequencies move across it. It also maintains a flat magnitude response when acoustically summed.

The primary advantage of a steeper roll-off slope is that it enables system designers to open up the bandwidths of drivers and get more efficiency over the frequency range. This has recently led to the unit becoming the FOH processing of choice on tour with Audio Analysts, Adlib Audio, Britannia Row, On Stage Audio and Promix/Electrotec Las Vegas, among others.

“The electrical summation between bands is razor flat,” says Martin ‘Ferrit’ Rowe of Promix/Electrotec. “They allowed me to put more power to the devices without fear of overload or over-excursion. We were setting off alarms in the car park.”

Yamaha
Approaching speaker processing with the idea that a complicated process, normally involving a substantial array of equipment, can be squeezed into a single rack space unit, Yamaha has developed a device that offers both pristine sound quality that ranks with its most advanced mixing desks and a broad range of processing functions.

Along with high-resolution 24-bit, 96-kHz audio, the SP2060 has  all the major functions involved in speaker processing built in, including: delay, peq, crossover, compression, limiting and an all-pass filter, which can be used to make minute adjustments to phase without altering gain. Yamaha’s large-scale integration (LSI) processing provides a dynamic range with a signal-to-noise ratio of over 110 dB, while analog stages benefit from Yamaha’s experience in high-end console design.

Detailed programming of the unit on a PC is enabled by the DME Designer software – also used to configure Yamaha’s top-of-the-line digital mixing engines. This allows programming of large-scale sound systems that use multiple devices such as SP2060 with the DME series and also enables integration and collective management of outputs.

Adamson
Aimed at either the touring or fixed installation markets, Adamson’s M Series processor is a complete four-input, eight-output digital loudspeaker management system equipped with the very latest in available technology.

32-bit (40-bit extended) floating point processors, the highest quality 24-bit analog converters available and high-bit DSP prevent noise and distortion induced by truncation errors of the commonly used 24-bit fixed-point devices. This results in lofty audio performance figures. The device has a typical un-weighted dynamic range of 115 dB, crosstalk of less than -100 dB and distortion of just 0.002 per cent.

FIR (Finite Impulse Response) linear phase or brick wall crossover filters are implemented in the system. FIR gives a linear phase response at the crossover frequency, which is preferable to conventional IIR (Infinite Impulse Response) filters.

Phase correction filters are also added for precise phase adjustment. Two individual crossovers per output are available. Butterworth, Bessel and Linkwitz Riley filter types provide slopes from six to 48 dB per octave.

The M Series Processor can be controlled or configured in real time on the front panel or with the M Series Processor Software accessed via an Ethernet network or RS-232 interface. A complete set of parameters includes I/O levels, delay, polarity, six bands of parametric eq per channel and full function limiters.

Precise frequency control is achievable with a single Hertz resolution and inputs and outputs can be routed in multiple configurations to meet any requirements.

Martin Audio
Carefully optimised double precision signal processing coupled with 24-bit conversion gives Martin Audio’s DX2 a dynamic range in excess of 117 dB, a sampling rate of 96 kHz and a bandwidth over 32 kHz. The digital inputs feature sample rate conversion, allowing sample rates from 32 kHz up to 192 kHz.

Utilising the SHARC DSP platform, the DX2 has a comprehensive range of digital processing available on all inputs and outputs. Inputs feature gain, variable delay and eight bands of eq. Each output features gain trim, variable delay up to 650 ms, fully configurable limiters, high and low pass crossover filters, polarity select and a further nine bands of parametric eq.

Inputs and outputs can be configured to accept either pro-audio level analog signals, or digital AES/EBU signals to interface seamlessly with industry standard digital consoles, signal processors and amplifiers. Password protected locking ensures tamper free operation, with full or partial locking available, depending on the level of security required, allowing for a wide variety of venues and climatic conditions.

VMB
Arkeops is the latest generation of VMB processors, which have been continually developed for the last ten years. VMB assures that the device uses absolutely the best converters available, ensuring very low distortion and a huge 120 dB dynamic range.

The Akeops allows the user to apply a filter to compensate for absortion losses caused by distance, relative humidity and temperature. Different distances can be calculated and compensated for at the outputs, each of which offers both an RMS compressor/limiter and a peak limiter. The first stage uses a RMS detector algorithm to obtain a high quality compression. The sound system can then gradually reach maximum power while maintaining clear sound, before the second stage is activated for a mechanical control and maximum speaker excursion.

The device allows speaker response data in magnitude and phase, according to the frequency imported. It allows data imports from acoustic measurement systems such as audio precision, Linear X LMS, Smaart Live, CLIO, DAAS 32, MLSSA, Acoustilyzer and CALSOD, among others.
 
Arkeops was recently put to use alongside a VMB Lynx sound system on the Park Stage at Glastonbury 2008 and has also been featured in a number of sizeable installations, including Mirror, a large nightclub in Valencia, Spain.

Klark Teknik
The signal processing specialist has expressed concerns that, because the practicality of the digital system controller has in recent years helped make it one of the fastest developing areas of signal processing, the audio performance of certain units has been overshadowed by functionality. The company insists that, where its own processor, the Helix, is concerned, no compromise has been made on either its feature set or sound quality.

The DN9848E has no preset routing and can be preprogrammed to perform virtually any system-control task. Limiters and compressors on all outputs and compressors on all inputs provide steadfast speaker control and protection, while ninety-six bands of fully parametric EQ allow for room and system eq. The device is equipped with enough processing power onboard to potentially allow every function to be available simultaneously.

Seven DN9848Es were recently installed within the impressive Terminal 5 at Heathrow Airport to drive speaker systems across the World Duty Free retail area. Brian Lumb, the MD of Pro Audio Systems, which carried out the installation, comments: “It was essential that each of the processors had four inputs and, in some cases, more than six outputs. The DN9848E is one of the few models available that provides this.”

Apex
Offering simultaneous use of 256 filters, Apex’s Intelli-X 48 boasts a 30-band constant-Q graphic eq, with eight-band parametric and tow-band shelving eq available on each input signal and also on the output. Two crossover filters with variable slope and types, including Butterworth, Bessel or Linkwitz-Riley, can be activated on each output channel, and comprehensive control of system set-ups can be achieved by combining delays on each input channel, together with the output channel delay and driver alignment delay per output.

The Intelli-X features a two-stage zero-overshoot limiter that preserves sonic transparency for light overshoots, but acts more aggressively if the signal overshoot is too high.

The first limiting stage has user-adjustable threshold, attack and release time and allows for short-term overshoots while reducing the average power output and keeping distortion low on sustained overshoots.

The threshold of the second stage is indicated in dBr, relative to the threshold of the first stage and can be set so that the brick wall limiter acts just before the amplifier clipping point, making it possible to perfectly match speaker and amplifier capabilities.

Lab.gruppen
With production of the Dolby Lake Processor (DLP) coming to an end, scores of sound companies, for which the device has become a touring standard, will be turning to Lab.gruppen’s powered loudspeaker management system to allow them to continue to benefit from the technology.

The PLM 10000Q combines networked digital signal distribution, drive processing, power amplification, load verification and performance monitoring in a single piece of hardware, complete with software interface that allows multiple units to be controlled from a single computer. The device contains two Dolby Lake Processor modules, each offering gain, delay, crossover slope, eq and limiting. DLP algorithms provide raised cosine equalization, linear phase crossovers, LimiterMax loudspeaker protection and Iso-Float ground isolation.

Raised cosine eq is the basis of the DLP’s Lake Mesa eq and Ideal Graphic eq. Mesa eq offers asymmetric filtering to match the responses of many loudspeaker systems, while the Ideal Graphic eq offers true sum-to-flat response, so that adjustments impart uniform boost and cut with greater selectivity. Dolby Lake Processing includes classical crossovers, which are selectable up to 48 dB per octave, and linear phase crossovers to limit lobing and off-axis cancellation, capable of slopes exceeding 180 dB per octave.

HK Audio
With Hardman Filter Technology (HFT), HK Audio’s DSM 2060 digital speaker management system is equipped with practical functions for both touring and fixed installations. The unit is designed to exceed standard requirements and offer audio quality of a level normally obtainable from considerably higher priced products.

The DSM 2060’s two inputs and six outputs can be configured separately for FOH and monitor use in touring applications, also allowing for a great deal of flexibility in fixed installation projects. Users can apply up to six parametric eqs, plus two shelving filters to each input and output channel. For setup of delay zones and time alignment in multi-amped systems, the device offers input delays up to 400 ms and output delays up to 80 ms. For speaker and driver protection different limiters can be applied to each output in steps as fine as 0.2 dB.

The fourth and eighth-order HFT filters unique to the DSM 2060 create crossover slopes of 36 dB and 52 dB and achieve absolutely minimal phase shift and group delay, even at maximum slopes, thereby maintaining a natural-sounding signal. As a result, HFT produces a very smooth response in the crossover region and faster roll-off rates, which in turn minimise distortion, permit lower crossover frequencies and safely expand the effective frequency range of the drivers.

When Dirk Bamberger, owner of the award-winning German discotheque Treffpunkt, opened Top Ten in Tübingen, south of Stuttgart, he enlisted Prolite Event to carry out the sound system installation. The company specified three DSM 2060s to tame an extensive array of HK Audio’s Contour series loudspeakers.

XTA
Culminating in the flagship 4in/8out DP448, XTA’s 4 Series is built around a completely new processing platform, running at a native sample rate of 96 kHz, which the company says has been “advanced to maintain the expected quality and useability, as the demands placed on professional audio systems continue to steadily increase”.

The range uses high-end 24-bit converters on the inputs and outputs, running at 96 kHz to give a bandwidth of over 30kHz and a dynamic range in excess of 116dB. With two or four fully balanced inputs, and up to eight fully balanced outputs, it is possible to design four two-way monitor systems, or DP226 configurations with an additional stereo processing channel, from a standard 1U rack unit can be designed. Any output may be fed from any input, or combination of inputs to forming a completely flexible matrix.

Prominent audio companies Audile and SSE both used XTA 4 Series devices across a number of the biggest festivals in the UK this summer. Between them, they handled stages at Reading and Leeds, V2008, Glastonbury, Bestival and many others. Rob Ashworth, director of Audile, which used DP448s to control Funktion-One systems comments:

“We strongly believe that an audio system should be transparent, from the signal entering the drive to sound exiting the speakers. The sound of a particular music style is shaped on the mixing console, so a correctly specified and set-up system will cope with any style. Our gear is chosen for its transparency and XTA drive is the best there is.”

dbx
The flagship of the popular DriveRack series, dbx’s 4800 system processor is designed primarily for live performance applications and features unique algorithms such as the proprietary Advanced Feedback Suppression (AFS), alongside the more familiar processing functions and control tools required for live sound reinforcement situations.

Providing four analog AES/EBU inputs and eight analog AES/EBU outputs, the DriveRack 4800 – also available with optional CobraNet card – features Harman Professional’s HiQnet protocol. This can be used to monitor and control signal routing as well as the processing of multiple DriveRack 4800 units from various locations, all using standard Ethernet equipment including routers and wireless access points.

Harman Professional’s System Architect software enables user assignable signal routing and control groups, as well as customised control panels for fully configurable systems. The software allows full and simultaneous control over the DriveRack 4800 and any other HiQnet-enabled Harman Professional products, such as Crown I-Tech amplifiers, JBL DrivePack loaded speakers, AKG WMS 4000 wireless microphones and the Studer Vista 8 mixing console.

Sabine
Now offering microphone preamp options and blank front-panel models, the revamped Sabine Navigator series takes advantage of Analog Devices’ powerful SHARC processors to handle all DSP. This negates the need to compile any files or settings, since all functions work simultaneously. Users are able to set feedback control filters and compressors on every input and output with no loss of performance.

One of the pioneers in the field of digital signal processing, Sabine’s research into digital filtering technology ensures excellent sound quality and reliability across all DSP functions, including eq, automatic mixing, routing, crossovers and gain management. The FBX Feedback Exterminator is one of numerous innovations developed by the company’s engineers. Blank front panel versions include Sabine’s new Automatic Mic Mixing function, with independent control of mic priority, attack, release, threshold and gain on each channel. Combined with the FBX Feedback Exterminator, this provides more gain before any feedback can interfere than conventional automatic mic mixers.