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FP+ power amplifiers and PLM Series Powered Loudspeaker Management systems
Westlake Village, CA (June 2008) – The world-famous Greek Theatre, a unique open-air amphitheater located at the edge of Griffith Park close to Hollywood, has earned an enviable reputation providing high-performance sound in an intimate environment. When the time came to replace the four-year old power amplifiers specified in The Greek’s original bid, Schubert Systems - the company responsible for supplying and operating its state-of-the-art PA rig - decided to integrate Lab.gruppen at what many consider to be the Number 1 US outdoor venue.
“I have admired the company’s product line for many years,” acknowledges company founder Dirk Schubert. “We received one of the first pallets of amps shipped to the US in 2002, and adopted Lab.gruppen for our systems the first time we listened to them. No other amplifier makes a rig sound as good as Lab.gruppen … period. I particularly like the new PLMs with built-in Dolby Lake processing, because they offer a truly integrated solution that is ideal for today's very challenging market.”
The new all-Lab.gruppen configuration, inaugurated in early May, features Lab.gruppen FP 10000Q four-channel amplifiers powering the main left and right JBL VerTec line arrays, with PLM Powered Loudspeaker Management four-channel models handling everything else: subwoofers, center, terrace and front fills plus delay speakers. Nederlander Concerts is exclusive operator of the 5,801-seat Greek Theatre.
Why the hybrid amplifier configuration? “Simply so that we can make sure the system is 110% reliable prior to our 2008 Summer Season,” replies Dustin Delker, head of sound at the Greek Theatre. “Last weekend we had [Latin legends] WAR and Tierra playing here [with special guests The Salas Brothers, MALO and Thee Midniters], and I wanted to try out the PLMs on the subwoofers, in particular, since they present a complex load for any amplifier. Then, when we have several weeks’ positive experience, we will probably swap out the FP+ Series amps for these remarkable PLM models. So far, the Lab.gruppen-powered VerTec system sounds remarkable.”
“We already use Dolby Lake Contour Processors here,” offers Tim Davis, front-of-house sound mixer and system technician, “so we are very familiar with the processing functions of the new PLMs. We can adjust the overall EQ profile for each concert, according to the needs of each individual act performing here. We like that both the stand-alone Dolby Lake [processors] and the PLMs use the same GUI interface, which we are already familiar with – it makes the learning curve much easer.
“If the visiting act's sound engineer is handling front-of-house, I can walk through the Theatre with a wireless-capable PC and adjust EQ settings to ensure consistent sound coverage throughout the entire amphitheater. The FP+ and PLM provide great sound even at lower SPLs. We are limited here [by an LA County Noise Ordinance] to a maximum 95 dB A-weighted, so we need to ensure a 20 Hz to 20 kHz response at levels lower than a normal arena SPL. These Lab.gruppen amps are fabulous in that critical 85-95 dB range, with plenty of dynamics.”
Conceived from the outset as a comprehensive drive system for any type of loudspeaker, the new PLM 10000Q seamlessly integrates networked digital signal distribution, drive processing (crossover, delay, EQ and limiting), power amplification and load verification plus performance monitoring into a single unit with a unified software controller accessing 100 user-programmable presets. The PLM’s built-in amplifier platform is based upon the highly successful and tour-tested FP+ Series, using Lab.gruppen’s patented Class TD output stage, an amplifier topology that approaches the exceptional efficiency of class D while retaining the sonic purity of proven class AB designs.
“We compared the FP+ Series amps on external Dolby Lake processors to the new PLMs with their built-in Lakes,” Delker recalls. “They sound virtually the same although I could detect a slight advantage from the PLMs – the lack of extra D-to-A and A-to-D stages in each channel might explain the improved headroom and transient response that I would probably attribute to latency delays. Also, we save space with this new configuration. Last year, our [competitive-brand] amps took up six racks; this year is occupies just two racks plus the Drive Rack and a single PLM at the FOH position to drive the delay speakers.” Currently the external Dolby Lake units are located at the FOH position – more space will be saved if the facility elects to use PLMs with built-in processing.
“What I like most about these new Lab.gruppen PLM 10000Q power amps,” Schubert concludes, “is that each amplifier becomes a multipurpose unit, with presets for any cabinet in our inventory, from subwoofers and side-fills, to full-range line array cabinets and monitor wedges. Flexibility is a major advantage for a sound-hire company like ours. At The Greek we only need one spare amplifier because every unit has all of the presets needed to run any part of the system.
“Also, the PLMs sound very, very good: powerful low-end, silky high-end, and ultra-smooth mid-range. They are capable of delivering full Lake Dolby processing with minimum latency” – 1.7 mS from analog-in to speaker-out – “which results from fast internal processing. There are many power amplifiers with internal loudspeaker processors we will not use because the latency makes them unacceptable. These PLMs are the only way to go!”
