1238DF SAM™ Studio Monitor

Active crossover operating at low signal levels.

Audio electronic crossovers allow to split the audio signal into separate frequency bands that can be separately routed to individual power amplifiers which then are connected to specific transducers optimized for a particular frequency band.

Active crossovers come in both digital and analogue varieties. Genelec digital active crossovers include additional signal processing, such as driver protection, delay, and equalization.

Genelec analogue active crossover filters contain electronic components that are operated at low signal levels suitable for power amplifier inputs. This is in contrast to passive crossovers that operate at the high signal levels of the power amplifier's outputs, having to handle high currents and in some cases high voltages.

In a typical 2-way system the active crossover needs two power amplifiers — one for the woofer and one for the tweeter.

The active crossover design offers multiple benefits:

• The frequency response becomes independent of any dynamic changes in the driver's electrical characteristics or the drive level.
• There is an increased flexibility and precision to adjust and fine tune each output frequency response for the specific drivers used.
• Each driver has its own signal processing and power amplifier. This isolates each driver from the drive signals handled by the other drivers, reducing inter-modulation distortion and overdriving problems.
• The ability to compensate for sensitivity variations between drivers.
• The possibility to compensate for the frequency and phase response anomalies associated with a driver’s characteristics within the intended pass-band.
• The flat frequency response of a high-quality active loudspeaker is a result of the combined effect of the crossover filter response, power amplifier responses and driver responses in a loudspeaker enclosure.

Using the active approach enables frequency response adjustments and optimization of the full loudspeaker system, placed in various room environments, without expensive external equalizers. The end result is a simpler, more reliable, efficient, consistent and precise active loudspeaker system.

Directivity Control Waveguide (DCW™) for flat on- and off-axis response.

A revolutionary approach was taken by Genelec in 1983 with the development of its Directivity Control Waveguide (DCW™) used at the time in an egg-shaped enclosure. The Genelec DCW technology developed and refined over more than 30 years greatly improves the performance of direct radiating multi-way monitors.

The DCW technology shapes the emitted wavefront in a controlled way, allowing predictable tailoring of the directivity (dispersion) pattern. To make the directivity uniform and smooth, the goal is to limit the radiation angle so that the stray radiation is reduced. It results in excellent flatness of the overall frequency response as well as uniform power response. This advanced DCW technology minimizes early reflections and provides a wide and controlled listening area achieving accurate sound reproduction on- and off-axis.

Minimized early reflections and controlled, constant directivity have another important advantage: the frequency balance of the room reverberation field is essentially the same as the direct field from the monitors. As a consequence, the monitoring system's performance is less dependent on room acoustic characteristics.

Sound image width and depth, critical components in any listening environment, are important not only for on-axis listening, but also off-axis. This accommodates not only the engineer doing his or her job, but also others in the listening field, as is so often the case in large control rooms.

DCW™ Technology key benefits:

• Flat on- and off-axis response for wider usable listening area
• Increased direct-to-reflected sound ratio for reduced control room coloration
• Improved stereo and sound stage imaging
• Increased drive unit sensitivity up to 6 dB
• Increased system maximum sound pressure level capacity
• Decreased drive unit distortion
• Reduced cabinet edge diffraction
• Reduced complete system distortion

Intelligent Signal Sensing (ISS™) for power consumption reduction in stand-by mode.

Introduced early 2013, Genelec’s Intelligent Signal-Sensing technology has been developed to meet with both European Union ErP Directives and the company’s own wider sustainability commitments.

The Intelligent Signal Sensing, ISS™ circuitry tracks the signal input of the loudspeaker and detects if it is in use. If the ISS circuit does not find any audio on the input for a period of time, it sets the loudspeaker to a low-power sleep state and the loudspeaker will consume less than 0.5 watts. When an input signal is detected, the loudspeaker immediately turns itself on. Basically, the loudspeaker system will start saving power as soon as work is interrupted.

Additionally an ‘ISS Disable’ switch is located on each product’s back plate next to the other room response controls. First, when the mains power switch of the loudspeaker is set to “ON”, the ISS™ auto-start function (low-power sleep state on/off) of the loudspeaker is active.

If this function is not desired, the ISS™ function can be disabled by setting the “ISS Disable” switch on the back panel to “ON” position. In this mode, the monitor is only powered on and off using the mains power switch.

Note that the mains power switch will always turn the monitor off completely.

Each transducer is driven by its own optimized amplifier.

Audio electronic crossovers allow to split the audio signal into separate frequency bands that can be separately routed to individual power amplifiers which then are connected to specific transducers optimized for a particular frequency band.

In a typical 2-way loudspeaker system, the active crossover needs two power amplifiers — one for the woofer and one for the tweeter. The power amplifiers are connected directly to the drivers of an active loudspeaker, resulting in the power amplifier’s load becoming much simpler and well known. Each driver-specific power amplifier has only a limited frequency range to amplify (the power amplifier is placed after the active crossover) and this adds to the ease of design.

The active design principle offers multiple benefits:

• The power amplifiers are directly connected to the speaker drivers, maximizing the control exerted by the power amplifier’s damping on the driver’s voice coil, reducing the consequences of dynamic changes in the driver electrical characteristics. This may improve the transient response of the system.
• There is a reduction in the power amplifier output requirement. With no energy lost in the passive crossover filter components, the amplifier power output requirements are reduced considerably (by up to 1/2 in some cases) without any reduction in the acoustic power output of the loudspeaker system. This can reduce costs and increase audio quality and system reliability.
• No loss between amplifier and driver units results in maximum acoustic efficiency
• Active technology can achieve superior sound output vs. size vs. low frequency cut-off performance
• All loudspeakers are delivered as a factory aligned system (amplifiers, crossover electronics and enclosure-driver systems)

Sophisticated drive unit protection circuitry for safe operation.

When working in critical audio production environments it is essential that monitoring systems remain reliable and functional at all times. One of the main reasons behind Genelec’s excellent success in broadcasting environments is the reliability of our products and a key element behind the reliability is the internal protection circuitry found in all products since 1978.

The protection circuitry prevents driver failures by detecting signal levels, and in case of sudden peaks or constantly too high levels, taking the signal level down automatically. Of course this feature does not affect the sound quality in any way when working within the specifications of the loudspeaker, but only prevents inadequate input signals from breaking the loudspeaker.

Protection circuitry features and benefits:

• Reduces the output level when required, (e.g. when driver voice coil temperature reaches the safe limit) which highly improves the system reliability
• Appropriate protection circuitry design in every loudspeaker and subwoofer enables to maximise system output sound level.