The EPAK™ 2500 is a four-way, active control and amplification system specifically designed for the KV2 Audio ES Series modular loudspeaker systems. It not only houses all signal processing and amplification but also controls allocation of power depending on the number of bass modules employed. Unlike other active speaker systems, the EPAK allows placement of critical (and heavy) electronics on stage - instead of inside the speaker modules (which may be flown or stacked where access is not possible.)

• Four-Way modular, 2500-Watt Control and Amplification System for use specifically with ES 1.0 Mid / High and Bass active-driven Modules
• High Frequency, 100-watt, Class AB – push pull – low intermodulation design
• Mid Frequency, 200-watt, Class AB – push pull – low intermodulation design
• Mid Bass, 600-watt, high-efficiency, current-enhancing switch mode technology with Linear Active Filter
• Bass, 1600-watt, high-efficiency, current-enhancing switch mode technology with Linear Active Filter
• Complete, on-board speaker system management including equalization, time correction, crossover filters, amplifier overdrive protection, system set-up and output level controls
• AC soft start circuitry with ON/OFF AC breaker switch provides thorough power protection
• Passive heat dissipation design with demand-sensitive forced cooling back-up system
• Setup provides selection and control of six different bass module setups
  Individual system and bass module output level controls
• Unique ability to select between two types of bass “character”–ATTACK and EXTENSION
• Professional enclosure using exterior-grade Baltic birch construction with wear resistant polymer coating
• Proprietary corner handle design for simplified handling and carrying
  Acetal copolymer high impact, low friction feet for easy cabinet movement
• Removable front cover holds all AC and speaker cables
  Included: One 13ft (4m) long speaker cable with AP4 connectors included for main bass module hook up (4-conductor, 13 gauge [2.5mm2] wire,)
• Included: One 20ft (6m) long speaker cable with AP6 connectors included for mid / high module hook up (6 conductor, 13 gauge [2.5mm2] wire)
• Included: Two 5ft (1.5m) long speaker cables with AP4 connectors included for bass module daisy chaining (4 conductor, 13 gauge [2.5mm2] wire)
• Included: One 20ft (6m) long AC3 conductor cable
  with market/model dependant connectors.

The equivalent of a dozen outboard components…or more.
To attempt to provide the sophisticated control built into the EPAK 2500, you’d need:

• A four-way electronic crossover
• Three parametric equalizers
• Four digital delay units
• Phase correction
• Four power amplifiers

Even if you employed an all-in-on “speaker control box” instead of the first three components, you’d still need a degree in acoustic engineering and sophisticated test equipment to achieve the optimization we’ve been able to build into the EPAK 2500. Plus, you would need four power amplifiers, each of which has to be overbuilt for unknown loads (a problem our amps don’t have). You would also need a road rack. After all of that, you still wouldn’t have the plug-and-play flexibility of switching bass modules…or some of the unique controls we’ve added.

Active speaker accuracy brought down to earth.
In our previous lives working at Fussion, Mackie Designs® and RCF™, sound contractors have often expressed to us one specific concern about active electronics: Because the amps and processing were built into the speakers, service could be a problem, especially when the boxes were flown high over a stage or in a large church sanctuary. (Corresponding complaint from anyone who ever had to load an active system in and out: the darn cabinets weigh a TON!).

Our response use to be: because active amplifiers are purpose-built designs specific to the loads and impedance swings of the transducers they’re driving, reliability is far FAR greater than with “blind” passive amps. And that’s true.

But now that we’re running our own company, we have a better response: The EPAK 2500. Amplification and control are back down behind the stage (or easily built into permanent installations).

The weight of the components is concentrated in one easily-moved, handle-laden cabinet, instead of inside the cabinets.

You need just one AC power cord instead of half a dozen.

And (never say never) should anything go wrong with an EPAK 2500, another one can be swapped in within minutes, even when the active-driven speakers are fifty feet in the air on a truss.

Four transducer- and load-specific amplifiers.

Unlike most other speaker manufacturers, KV2 Audio is equally expert in electronic design — in fact, we’re thirty-year veterans at building rugged, high-current power amps.
When you’re able to perfectly match an amp with a transducer, you unlock incredible performance that is impossible with passive systems. The amplifier can perfectly handle the impedance swings of the transducer. It can deliver exactly the right amount — and type of power. Reliability goes up dramatically as does sound quality.

Each amplifier in the EPAK 2500 perfectly compliments the transducers it’s coupled to. They are therefore very different from each other with respect to construction and purpose.

Mid / High Amplifiers. Both the mid and high frequency amplifiers inside the EPAK 2500 are Class AB, Push-Pull amplifier circuits using Metal Oxide Silicon Field Effect Transistors (MOSFET) output stage devices. The entire performance strategy for this type of design is based on producing the lowest intermodulation distortion possible and the highest audio quality in the critical mid and high operating bands. Both amplifiers are coupled to the mid /high drivers through transformer balanced speaker outputs.

Mid Bass and Low Frequency Amplifiers. For these frequency ranges, we’ve selected a very high efficiency and refined low frequency amplifier topology.

The unique part of the design is in the voltage amplifier’s ideal method in supplying current to the output stage. It’s based on a switcher design that supplies current both in its on and off position. It is the only amplifier system known to increase current under phase shift conditions encountered with large diaphragm woofers. The result is a dramatic improvement in the control of the speakers and superior bass reproduction quality. The system is also 95% efficient lowering typical amplifier losses and eliminating the need for forced cooling systems.

Robust mechanical design.
The EPAK 2500 is enclosed in a road-rugged Baltic Birch cabinet with two corner handles, acetal copolymer low friction, high density feet and a removable front panel with built-in cable storage compartment.

All electronic circuit boards are mounted on an extensive aluminum heat sink assembly that provides robust and consistent passive cooling backed up by an electronic forced cooling system. For additional reliability, the electronics mechanical assembly is mounted on an independent suspension system that isolates it from the shocks and impacts typically encountered on the road.

Easy-to-use controls…including a couple of unique new ones.
The first thing you do after opening the EPAK 2500 is determine what combination of bass modules you’re going to use along with an ES 1.0 Mid /High module. A six-position switch allows the selection of the following combinations:

• One ES 1.5 single fifteen-inch compact bass module
• Two ES 1.5 single fifteen-inch compact bass modules
• Three ES 1.5 single fifteen-inch compact bass module
• One ES 2.5 double fifteen-inch high output bass module
• One ES 1.5 and one ES 1.8 single eighteen-inch high output bass module
• Two ES 1.8 single eighteen-inch high output bass modules

Although the EPAK 2500 actively drives a single ES 1.0 Mid /High module, you can set up two ES 1.0 cabinets to work together in a single loudspeaker system using two EPAK 2500’s per side. A two-position switch allows the EPAK 2500 to engage a specific set of filters and operating parameters for using either one or two ES 1.0’s per side.

System Level and Bass Level Control. Rotary knobs allows level control adjustments between –6 dB and +6dB. System Level affects the entire loudspeaker system including bass modules; Bass Level affects the output level of the bass modules only.

EXTENSION and ATTACK are “why-didn’t-anyone-else-think of-it-before” features that come from having electronic as well as acoustic design expertise. KV2 Audio has developed a proprietary electronic bass management circuit that provides deep, controlled bass extension. This super-fast circuit is completely transparent and is not based on changes in equalization, addition of limiters or the integration of compression to the signal.

Bass EXTENSION is generated by first “charging” the bass extension circuit with the high-energy transient signal that occurs below 80Hz to 100Hz. The circuit then releases the energy over a slightly longer period of time, about 15 milliseconds. The resulting amount of total power is the same as found in the original signal, but the addition of time and the reduction in peak signal results in large diameter woofers having more time to reproduce long wavelength information.

When ATTACK is selected, the EPAK 2500 uses its 1600 watts of power to reproduce the input signal in the low frequency band pass with control and authority. The ES system was developed primarily for use in live applications where peak transient signals are typically 10-15dB above pre-recorded levels. Available low frequency amplifier power is primarily used for reproduction of these transients. Every KV2 bass module has been developed to provide depth, definition but especially attack that can be experienced at substantial distances away from the enclosure. The ATTACK setting provides true, pure, high dynamic bass reproduction.

Three system LEDS show various modes of operation. First there is a POWER ON LED that indicates that the unit is ON and is ready to operate. There is also a LED to indicate that signal is present. This is helpful for trouble shooting signal path problems. The EPAK 2500 uses a very fast, RMS power limiting system that when engaged turns the GREEN SIGNAL PRESENT LED to RED. To disengage the limiter, simply lower the input signal level or the master level control. A RED LED indicates that the unit has entered a thermal shutdown / auto reset condition. The unit will automatically reset when the temperature has reached safe operating levels.

The ON /OFF control (on the lower control panel) is a combination power / circuit breaker switch which provides secure, safe protection from AC spikes and associated problems.

There are also two speaker outputs on the panel, one is a female AP6 connector for the ES 1.0 mid / high module. The other is a four pin female AP4 connector for any of the KV2 Audio bass modules.