Technical Glossary: Genelec proprietary technologies, Technical specifications, Audio & physics terminology
Genelec proprietary technologies
Directivity Control Waveguide (DCW™)
Genelec's revolutionary Directivity Control Waveguide technology, first developed in the early 80's, can greatly improve the performance of a direct radiating multi-way monitor. The DCW is designed individually for each monitor and matches the frequency response and directivity characteristics of the drivers in the monitor. This results in an excellent flatness of the overall frequency response for on- and off-axis listening positions and improves the audio reproduction neutrality in acoustically challenged listening rooms compared to conventional designs.
Genelec AccuSmooth is a proprietary frequency response smoothing algorithm that provides a higher resolution i.e. a narrower smoothing bandwidth at low frequencies compared with the standard 1/3 octave smoothing and similar resolution at high frequencies. It is used by AutoCal™ to ensure accurate placement of equalising filters at critical or problematic bass frequencies. It also enables the customers to evaluate the low frequency effects in a more detailed way.
Genelec proprietary acoustical measurement and monitoring system alignment and performance-optimising calibration tool, Genelec AutoCal, is built in Genelec GLM™ and GLM.SE™ software. AutoCal utilises built-in test signal generators inside every Genelec SAM monitor and subwoofer to acoustically measure, optimise and align all products in a monitoring system.
Genelec AutoPhase is a part of the Genelec AutoCal calibration tool. It aligns the subwoofer phase at the crossover frequency in the system with the designated monitor(s).
GLM™ & GLM.SE™ Control Networks
The Genelec Loudspeaker Manager and Genelec Loudspeaker Manager for Small Environments control networks are proprietary Genelec networking technologies that allow setting, reading and controlling monitors and subwoofers on the GLM/GLM.SE network. Settings of a multichannel system can be adjusted very rapidly by opening up a System Setup file, which causes all system settings to be applied and all internal settings to be automatically communicated and set in all monitors and subwoofers.
Intelligent Signal Sensing (ISS™)
Genelec's ISS function saves energy through automated sleep mode function. It tracks the signal input to the monitor detecting whether it is being used. If the ISS circuit does not find any audio input for a period of time, it automatically sets the monitor amplifier to a low-power sleep state. The monitor automatically starts up again once an input signal is detected. This functionality meets with both European Union ErP Directives and Genelec's own wider sustainability commitments.
Iso-Pod™ (Isolation Positioner & Decoupler)
The Genelec Iso-Pod stand mechanically isolates the monitor from its mounting or standing surface which helps to eliminate sound colouration caused by mechanical vibrations. It also allows the monitor to be tilted and orientated so that the monitor's acoustical axis can point directly at the listener.
Laminar Integral Port (LIP™)
The Laminar Integral Port is a highly efficient flow-optimised dual reflex port system integrated in Genelec's innovative Natural Composite Enclosure™ material during the enclosure moulding process. It is designed to achieve very low distortion and high output levels, as well as to further increase the rigidity of the enclosure, reducing also the likelihood of cabinet surface vibration.
Laminar Spiral Enclosure (LSE™)
The LSE Series subwoofers feature the innovative Genelec Laminar Spiral Enclosure bass reflex cabinet. The LSE design provides excellent laminar air flow in a highly efficient reflex port with minimal turbulence noise. This enables optimal integration of a very long and efficient reflex port into a physically small enclosure.
Minimum Diffraction Coaxial (MDC™)
The MDC driver consists of an integrated midrange-diaphragm-suspension-tweeter. The coaxial dome tweeter assembly is in the center. The midrange diaphragm has no conventional spider and its suspension is made of foam over the entire cone. Both midrange-diaphragm-tweeter and midrange diaphragm-DCW joints are totally smooth and diffraction-free. This breakthrough in coaxial design integrated in a DCW provides precise imaging and outstanding sound quality on- and off-axis which leads to clarity and definition of the inner details of the music.
Minimum Diffraction Enclosure (MDE™)
Eliminating edge diffractions is needed in order to improve the flatness of the frequency response and the power response. Genelec's highly innovative Minimum Diffraction Enclosures are optimised to match the properties of the monitors' drivers. They feature rounded as well as gently curved edges. In addition to achieving an unsurpassed flatness of the frequency response, such enclosures yield superb sound stage imaging qualities.
Acoustical measurements at multiple positions are a method of spatial averaging used in Genelec AutoCal. MultiPoint measurement method enables optimising the acoustical settings of Genelec SAM monitors over a given listening area.
Natural Composite Enclosure (NCE™)
The Natural Composite Enclosure of the Genelec M Series products is made of a fully recyclable injection-mouldable wood-based composite material. The wood fibers contained in the material provide high internal losses which contribute to excellent enclosure performance. The injection moulding process allows the production of acoustically optimised shapes and design of structures with small wall thicknesses.
Room Response Controls
The room response controls are a collection of controls built into Genelec monitors and subwoofers which are used to compensate and eliminate acoustical problems generated by the room and which are present in the monitor or subwoofer frequency responses at the listening position.
Acoustical measurements taken at a single position in the room, i.e. at the main monitoring position only, is used as the standard method by Genelec AutoCal when optimising the Acoustical Settings of Genelec SAM monitors.
Smart Active Monitoring (SAM™)
Genelec Smart Active Monitoring concept describes a system thinking achieved by utilising Genelec SAM monitors which contain elaborate digital signal processing (DSP), Genelec automatic calibration (AutoCal) and Genelec Loudspeaker Manager (GLM) software. The complete package allows automatic calibration of the system in different size of setups, helping to eliminate room-related acoustical problems and allowing to optimise multiple positions in the same room or a listening area.
Audio & physics terminology
A-weighting is related to measuring the sound pressure level. Weighting is used because the human hearing system is more sensitive at some frequencies (500 Hz...8 kHz) than others (very low or very high frequencies). A-weighting changes the pressure readings according to the frequency in calculating a value representing the subjective impression created by the sound.
An active crossover uses electronics at low signal level and has a well-defined and precise frequency response, unchanged by the signal level or power output of the monitor. Traditional passive crossovers operate at high signal levels on the power amplifier output and the filter characteristics do not typically remain constant when the signal level varies. Active crossover filters can have analog or digital signal processing.
Bass management is a filtering method that enables to direct the lowest frequencies in the audio signals to one or more subwoofers instead of monitors. This can be the low frequency content of the full-bandwidth audio channels. Parts of the entire LFE (low frequency effects) audio channel can also be bass-managed. Bass management provides several benefits. The monitors can output higher sound level. The monitors can be placed with more freedom to control the acoustical environment and to improve the quality of the audio reproduction.
A Class-D amplifier uses switching technology in driving power handling semi-conductor devices (usually MOSFETs). The power devices are either fully conducting or fully off. Class-D amplifiers work by varying the duty cycle of the output according to the signal voltage. Theoretical efficiency of Class-D amplifiers can be very high, ultimately 100%, in practice well over 90%. By contrast, an ideal Class AB amplifier has a theoretical maximum efficiency of 78% and pure Class A amplifiers have a theoretical maximum efficiency of 50%.
The decibel (dB) is a representation of magnitude relative to a reference level on a logarithmic scale. Since it is expressed as a ratio of two physical quantities, it is a dimensionless unit.
Digital Signal Processing (DSP) uses numerical presentations of the audio signal in signal processing.
Flush mounting and half-space
When a plane surface, such as a wall or floor, limits the radiation of a monitor, the radiation occurs in a half space. A method of monitor installation close to a half-space is flush mounting where the front of the monitor is flush with the wall and the monitor is installed in a recess. This has several benefits such as improved low frequency efficiency, elimination of rear wall cancellation, and lack of cabinet edge diffraction.
Free-standing or free field installation
When a monitor can radiate sound without any limitation of obstacles or surfaces it is said to radiate in the free field and the monitor is said to be free-standing. Genelec monitors have a flat frequency response in free field.
Magnetic shielding reduces the magnetic field around the monitor. Drivers have permanent magnets and are magnetically shielded to minimise stray magnetic fields. The stray magnetic fields can disturb magnetic compasses and other equipment that depend on static magnetic field.
Radiation space refers to the free volume around the monitor or subwoofer where the sound can spread. The radiation space of a loudspeaker can also be limited by the radiation characteristics of the monitor itself.
The reflex port is an acoustically optimised opening in a monitor or subwoofer enclosure which enhances the reproduction of the lowest audio frequencies.
The cut-off frequency describes the higher and lower limits of the audible frequency range. The standard values used by Genelec are -3 dB and -6 dB below the average output level in the monitor pass-band.
The dynamic range measures the ratio between the strongest output signal and the output noise level, limiting the smallest possible output. The concepts of signal-to-noise ratio (SNR) and the dynamic range are closely related. The difference between them is that SNR measures the ratio between an arbitrary signal level, not necessarily the most powerful signal possible such as the dynamic range, and the no-signal noise level.
The frequency response is measured in the free field, i.e. in an anechoic chamber. The frequency response defines a frequency range guaranteed to be flat on the acoustical axis within the set specification in all products. The specification used by Genelec depends on the product. Typically one of the following tolerances is used for Genelec specifications: ± 1 dB, ± 2 dB, ± 2.5 dB, ± 3 dB.
Signal-to-noise ratio (SNR)
SNR is a ratio of the test signal to the no-signal noise level. It is often expressed in decibels.
Sound pressure level (SPL)
Sound pressure level describes the pressure of the sound wave, expressed in decibels (dB) relative to the reference pressure of 20 µP (micro-pascals) or N/m2. 0 dB SPL is the average threshold of hearing a sound for humans at 1 kHz frequency for young healthy adults.
Total harmonic distortion (THD)
The total harmonic distortion describes the ratio of the wanted signal to all the harmonic distortion produced by the monitor or loudspeaker. Genelec specifies the total harmonic distortion for the whole monitoring system, from the input to the output, in two frequency bands.