Lake Processing

The robust power platform of D Series and PLM Series works hand-in-glove with dual integrated Lake Processing modules, with features such as Raised Cosine Equalization™, Limiter Max™ peak and RMS limiters, and Iso-Float™ ground isolation.


The advanced technology of Lake Processing provides audio professionals with unparalleled power to shape and optimize sound in a variety of environments. Regardless of the make or type of loudspeaker system, the venue size or acoustics, or the program material, Lake Processing will help you create a more consistent sound with less time and hassle in system set-up.

LM 26 and PLM Series devices contain two full-featured Lake Processor modules, each offering precise settings for gain, delay, crossover slope, equalization, and limiting. Exclusive Lake Processing algorithms are included for Raised Cosine Equalization, and linear phase. In addition, Lake Processing also incorporates Iso-Float™ ground isolation, a cost-effective and audibly superior alternative to isolation transformers.

Mesa EQ

Mesa EQ gives sound engineers a faster, more effective optimization tool—one that can truly match the asymmetrical responses of loudspeakers.

Ideal Graphic EQ

Ideal Graphic EQ is not implemented in the traditional manner, but instead uses Raised Cosine Filters that provide better selectivity than conventional filters. Ideal Graphic EQ filters sum to flat, thus providing a true response equalizer. This results in controls that provide exactly what is expected by the end user.

Raised Cosine Equalization

Raised Cosine Equalization is the foundation underlying Ideal Graphic EQ™ and Lake Mesa EQ™, the two revolutionary EQ interfaces provided by the Lake® Processor.

The graphic above shows boost shapes typical of raised cosine (blue) and conventional (red) equalization. Note the increased selectivity of the raised cosine shape.

The development of the Lake Mesa EQ was a significant advance in EQ technology. While other processors provide standard symmetrical boost and cut functions, the Mesa EQ offers asymmetric filtering, with the ability to separate the sides of a parametric section, change center frequencies, and independently adjust slopes.

The Mesa EQ gives sound engineers a faster, more effective optimization tool—one that can truly match the asymmetrical responses of loudspeakers.

Classical Crossovers

Bessel, Butterworth and Linkwitz-Riley crossovers are provided, selectable up to 48 dB per octave. The crossover interface also allows you to quickly add low shelf, high shelf, and parametric filters to each output. These filters use the latest in digital signal processing technology, maintaining their symmetrical shape at high frequencies.

You can also build your own custom crossover functions by enabling or disabling high pass and low pass filters on any output channel.

Linear Phase Crossovers

Linear phase crossovers are another feature separating Lake Processing technology from ordinary processors. Linear phase crossovers can match traditional crossover slopes, such as 24 dB per octave and 48 dB per octave, when desired. But they are also capable of transition slopes exceeding 180 dB per octave.

These slopes offer dramatic benefits when applied to various types of loudspeaker arrays. Off-axis lobing and cancellation between loudspeakers are dramatically reduced. Greater control over slopes means that different speaker cabinet types can be more easily mixed and matched. Also, a loudspeaker’s impulse response is significantly improved, providing a time-coherent wavefront.

Additionally, improvements of up to 3 dB or more in acoustic output power may be expected in some frequency ranges.

LimiterMax™ & Iso-Float™
– LimiterMax Loudspeaker Protection

LimiterMax is a significant advance in limiter technologies, combining an exclusive true-RMS limiter, an advanced peak limiter capable of instantaneous attack time (adjustable by the user), and additional sophisticated signal processing.

Iso-Float Ground Isolation: A Better Way to Avoid Ground Loops

Iso-Float technology combines the benefits of transformer-coupled isolation with the advantages of clean, direct-coupled inputs.

In the Lake processor input section, the audio converters are galvanically isolated, and not connected to the main ground. High-speed transformers and opto-isolators create a barrier between the processor and possible grounding aberrations from the outside electrical environment.

Additionally, you can change the grounding of any input or output remotely through the Lake® Controller software interface.

While isolation transformers are typically an expensive option for many processors, Iso-Float is standard in the LM 26 and PLM Series units.