The lineage of APM speakers stretches from the first model, the APM-8 of the "Esprit" series, in 1979 to the latest APM-66ES. This is the unchanging philosophy behind Sony's Hi-Fi audio - to convey music in its purest form, without any additives or loss of anything. By reproducing only the music signal, the emotion of music emerges from the APM-66ES. This APM 3-way speaker has been perfected to the next level, with an amorphous diamond tweeter, a multi-point drive woofer, and an acoustically rounded enclosure. The natural sound field and detailed depiction of instruments and vocals with their natural color and texture. The deep emotion and flavor of music is born from here.
A 9cm² APM tweeter made from amorphous diamond, a new material that provides high resolution and crystal clear high frequencies. After years of research, Sony has succeeded in depositing this new material onto an aluminum skin material. The synergistic effect of its high sound speed value, high rigidity, and aluminum honeycomb structure has resulted in a diaphragm that has excellent transient characteristics and produces clear playback sound without any quirks, making it suitable for the digital audio era. In addition, the voice coil uses lightweight and highly efficient copper-clad aluminum edgewise wire. The magnetic circuit is equipped with the strongest strontium ferrite magnet in its class, and a magnetic fluid with high heat dissipation and damping effects is injected into the voice coil gap. It reproduces high frequencies with a high level of transparency that vividly depicts even the subtle details of music. A 48cm² APM type midrange speaker with double-sided drive that reproduces vocals beautifully and freely. The midrange is the band where the fundamental tones of musical sounds are concentrated. The quality of vocal reproduction in particular is greatly affected by the quality of the midrange. The APM-66ES also incorporates new technology here. It uses a three-layered reinforced aluminum skin material based on aluminum. This is a reinforced aluminum material with fine internal cavities that has been treated with vibration damping, which increases rigidity while also reducing internal loss. The sweet spots of the skin material in front and behind the diaphragm are driven on both sides. This has greatly improved the rise and smoothness of the sound. In addition, the magnetic circuit is designed to be low distortion with a T-shaped pole piece, a perforated yoke, and a copper cap, and is highly efficient with the largest strontium ferrite magnet in its class and an oxygen-free copper-coated aluminum edgewise voice coil. It beautifully depicts rich, lustrous vocals, as well as the color and warmth of music. In addition, by using a large back chamber and setting the lowest resonance frequency low, the transition from the mid-range to the low-range is extremely smooth. A 424cm² APM woofer with multi-point drive system produces rich, firm bass. The aluminum honeycomb diaphragm is driven by multiple armatures directly connected to the voice coil, effectively canceling split vibrations beyond the usable frequency band. This design concept has been expanded to a total of eight armatures, canceling split vibrations up to higher modes. This achieves a pistonic motion band approximately five times (compared to our previous model) that of a comparable cone-type woofer, achieving a wide, flat playback band up to 4kHz. At the same time, distortion has been significantly reduced. To fully utilize the benefits of this drive system, the woofers are equipped with a powerful magnetic circuit with a low distortion design that includes a T-shaped pole piece with excellent magnetic flux symmetry and a perforated yoke that reduces back pressure on the diaphragm. In addition, the woofers are equipped with a high heat-resistant, high-rigidity armature.
Main specifications: Format: 3-way phase inversion type; Speakers used: 424cm² APM type for bass, 48cm² APM type for midrange, 9cm² APM type for treble; Impedance: 6ohm; Rated maximum input: 100W; Instantaneous maximum input: 200W; Output sound pressure level: 90dB/W/m; Effective frequency band: 28-45,000Hz; Crossover frequency: 600Hz, 4.5kHz; Size: 380 (width) x 660 (height) x 365 (depth) mm Weight: 27 kg