FBT DLM26 Speaker Management Processor

The FBT DLM26 is a DSP-based digital loudspeaker management signal processor with two inputs and six outputs, making it perfect for fixed installations and live events. It integrates the functionalities of a variety of traditional products into a single 1U box with extensive PC remote control capabilities. With high hi-end AKM5392 24bit A/D converters and AKM 4396 24bit D/A converters, the DLM 26 delivers exceptional audio quality. Carefully designed double precision signal processing combined with 24bit conversion ensures a dynamic range of >110db.

The unit can operate in either STANDARD or DCL mode. In the first mode, the crossover can be configured in two ways: 2x2 way + SUB, 2x3 way, or 6 way, with the inputs L, R, and L+R freely assignable to each output.

The unit can be set to 3ch DCL, 2ch DCL Plus 2ch standard, or 1ch DCL + 4ch standard in DCL mode. DCL stands for double compressor limiter, and each DCL channel has a double band limiter and compressor with a LO/HI split frequency that can be assigned. This is a unique property of digital processors, and it's highly important for protecting two-way passive filters in the crossover between the LF woofer and the HF speaker. With DCL mode, you can specify two different protection thresholds for the woofer and driver, with the split frequency matching the passive crossover frequency.

Each input features 5 completely programmable filters, a 288.66ms maximum delay in 6.8us steps, and gain.

Rows of 6 level LED + 1 clip led display the 2 input levels, whereas rows of 5 level LED + 1 clip led + 1 Limiter led display the 6 output levels. There are two analogue inputs, one stereo digital SPDIF input, and six analogue outputs on the unit.
There are both input and output connecting functions available.
When a parameter is changed, a function allows ramps to close the output level.

When the unit is utilised live and tiny modifications to the set parameter are required...on the fly, this function can be disabled.

The PC SW for remote control by RS485 or USB allows up to 32 units to be connected in a network and control all processor parameters, as well as show the phase of filter settings and alter the RMS compressor and Peak limiter graphically. Up to 64 memory with security lockout and two password levels are included in the entire standard specification.

Special and new features:

• Hi-pass/Lo-pass/Shelving custom Q second order filters
• RMS compressor and PEAK limiter on each output channel with time constant and algorithm optimized for speaker thermal and mechanical protection while maximizing the output with no audible distortion
• Input channel L, R or L + R freely assignable to each output channel
• Double Compressor Limiter Mode (DCL) with two band RMS compressor and Peak limiter with adjustable HP / LP split frequency and separate parameter adj. This is an exclusive and very useful feature in general purpose digital processors
• ALL PASS first and second order filters useful for Cardioid SUB configurations, very precise phase crossover alignment, special pattern control array, alignment between different speakers and systems.

Each output has 4 fully configurable filters, a delay of 288.66ms max in step of 6.8us, gain, phase, LO-pass/Hi-pass crossover from 6 to 24db/Oct with standard or custom Q, RMS compressor with soft knee and peak limiter.