Extended phase precision driver
To reproduce music with enhanced spatial sound expressivity, the wavefronts of the sounds emanating from the speaker must all be aligned when they reach the listener, regardless of the listening position. The point source concept is one of the ideal approaches to achieve this.
To achieve point source reproduction, the coaxial configuration was adopted and combined with the originally shaped Linear Phase Plug for phase alignment and the Smooth Flow diaphragm, which features a flat diaphragm and smooth edge shape for minimal sound reflection.
The SB-G90M2’s 2-way coaxial speaker unit has been redesigned to reproduce the mid- and high-frequency ranges for clear sound image localization and high sound quality that delivers smooth, emotionally charged music reproduction, while retaining Technics’ relentless pursuit of point source and linear phase concepts.
Linear phase plug
The originally shaped acoustic plug is positioned on the front of the tweeter diaphragm and provides high-resolution sound reproduction and a wide soundstage.
The tip of the linear phase plug is made of high-modulus, high-density brass material. It prevents the plug from vibrating unnecessarily due to the vibrations of the midrange driver and thus ensures a clear and low-distortion sound.
Smooth flow membrane
When a sound wave propagates along an irregular surface, its wavefront is disturbed by the irregularities of the surface, resulting in a degradation of the frequency characteristics, especially at high frequencies with short wavelengths.
The cone of the midrange driver, which is part of the coaxial Speaker, has a flat shape with a smooth edge to reduce sound reflections so that the disturbance of the sounds radiated by the cone is minimized, resulting in excellent frequency response, phase characteristics and wide directivity. This configuration achieves a wide soundstage and a smooth and powerful midrange and treble.
Balanced driver mounting architecture
Unwanted vibrations generated by the baffle have been further reduced by improving the vents using CAE, and the one-piece woofer baffle penetrates the bottom plate to achieve greater rigidity. In addition, the optimized vents improve the distribution of the sound emitted from the rear of the Speaker for better response. In addition, the baffle for the coaxial speakers is separated from the baffle for the woofers to avoid mutual interference. Together they improve the clarity of the sound and the three-dimensional representation of the sound field.
To reproduce the sound of music with a high S/N ratio, all unwanted sound sources must be completely eliminated. To this end, the balanced driver mounting architecture inherited from the previous SB-G90 model has been further optimized through extensive CAE analysis, and the baffle has been redesigned for secure mounting of the Speaker.
In addition, the rigidity of the entire cabinet has been increased to take advantage of the balanced driver mounting. The strength and shape of each part that makes up the coaxial speaker has been carefully checked to eliminate unwanted vibration and noise as completely as possible. In addition, a sound path structure is provided inside the cabinet. This new and unique structure effectively eliminates standing waves that cause a resonant peak.
Standing wave termination structure
A resonance, called a standing wave, is normally generated inside the cabinet of the speaker – by sound of a certain frequency, which is determined by the size of the cabinet. The most common method of eliminating the standing wave is to install sound-absorbing material in the cabinet.
However, since sound-absorbing material also absorbs sound at frequencies other than that produced by a standing wave, it takes away some of the dynamics and liveliness of the reproduced sound. As a countermeasure, a sound path structure is provided at the bottom of the woofer enclosure to guide the standing waves.
Sound-absorbing material is placed at the point in the sound path where the speed of sound is highest. This allows efficient elimination of standing waves, which are the cause of resonance peaks, with a minimal amount of sound absorbing material. (Patented)
This structure allows the use of all the information necessary for accurate music reproduction, so that the speaker achieves a more vivid and natural sound in the mid and low frequency range.
- Speaker-type: Floor standing speaker
- Speaker system: 2-way speaker system
- Efficiency/sound pressure 2.83V/1m (dB): 88
- rated power handling (W): 100
- music power handling (W): 200
- min. recommended amplifier power (W): 40
- max. recommended amplifier power (W): 150
- frequency response lower limit (Hz): 27
- frequency response upper limit (Hz): 100000
- Transition Freq. 1st bass-2nd bass (Hz): 480
- Transition Freq. low/mid/high frequency (Hz): 3200
- Number of mid-tweeters: 1
- Number of woofers: 2
- diameter mid-tweeter (cm): 16
- diameter woofer (cm): 16
- Number of speaker boxes: 1
- width (cm): 30.2
- height (cm): 111.4
- depth (cm): 37.5
- weight (kg): 32
- 38 kg