The Infinity Prelude Forty is a speaker system released in 2008 to celebrate Infinity Systems' 40th anniversary. It features a slim profile and utilizes proprietary Maximum Radiating Surface (MRS) flat panel driver technology. The Prelude Forty aims to appeal to both audiophiles and those with an eye for design. Its aesthetic includes a sleek design with removable black grilles. The sound quality is noted for its smoothness and accurate tonal balance, allowing for precise stereo imaging and a wide dynamic range. Each speaker cabinet is equipped with four MRS flat panel drivers: two midrange drivers and two midbass drivers, crafted from the company's innovative Ceramic Metal Matrix Diaphragm (CMMD) material, which provides ultra-low mass and excellent rigidity for outstanding sonic resolution. The drivers utilize elliptical voice coils and neodymium magnets for improved efficiency, while the Same-Plane Surround technology reduces distortion by keeping the surround and diaphragm aligned. High frequencies are handled by a CMMD tweeter with a frequency response exceeding 40kHz, coupled with a cast-aluminum Constant Acoustic Impedance waveguide for enhanced clarity. The bass response is reinforced by dual 8-inch CMMD woofers featuring ribbon voice coils and high-quality components. The internal structure of the enclosure is extensively braced to prevent resonances, ensuring a clear sound. The speakers have a usable frequency response from 42Hz to 40kHz, with a sensitivity of 85dB and a nominal impedance of 8 ohms, suitable for amplifiers ranging from 50 to 250 watts RMS. They are available in high gloss black, cherry, and rosewood finishes, priced at around USD $6,000 each.

The Infinity Prelude Forty is a speaker system released in 2008 to celebrate Infinity Systems' 40th anniversary. It features a slim profile and utilizes proprietary Maximum Radiating Surface (MRS) flat panel driver technology. The Prelude Forty aims to appeal to both audiophiles and those with an eye for design. Its aesthetic includes a sleek design with removable black grilles. The sound quality is noted for its smoothness and accurate tonal balance, allowing for precise stereo imaging and a wide dynamic range. Each speaker cabinet is equipped with four MRS flat panel drivers: two midrange drivers and two midbass drivers, crafted from the company's innovative Ceramic Metal Matrix Diaphragm (CMMD) material, which provides ultra-low mass and excellent rigidity for outstanding sonic resolution. The drivers utilize elliptical voice coils and neodymium magnets for improved efficiency, while the Same-Plane Surround technology reduces distortion by keeping the surround and diaphragm aligned. High frequencies are handled by a CMMD tweeter with a frequency response exceeding 40kHz, coupled with a cast-aluminum Constant Acoustic Impedance waveguide for enhanced clarity. The bass response is reinforced by dual 8-inch CMMD woofers featuring ribbon voice coils and high-quality components. The internal structure of the enclosure is extensively braced to prevent resonances, ensuring a clear sound. The speakers have a usable frequency response from 42Hz to 40kHz, with a sensitivity of 85dB and a nominal impedance of 8 ohms, suitable for amplifiers ranging from 50 to 250 watts RMS. They are available in high gloss black, cherry, and rosewood finishes, priced at around USD $6,000 each.