Sigma OB

About the Sigma OB

The Sigma OB is a passive floorstanding speaker from Tekton Design that employs a proprietary open-baffle hybrid technology. This design uses a front-mounted 1-inch tweeter and an 8-inch midrange/bass driver, combined with a rear-mounted 8-inch nullification driver that creates an acoustical mass transformer. This converts the open-baffle dipole into a monopole low-frequency source, improving bass efficiency and extension. The speaker features a bass reflex enclosure with front ports that vent low-frequency energy from the rear nullification driver. It has a frequency response from 35 Hz to 30 kHz, a nominal impedance of 6 ohms, and a sensitivity of 93 dB. The Sigma OB measures approximately 43.5 cm wide, 109.2 cm high, and 36.9 cm deep, weighing about 58 pounds (26.3 kg). It is noted for its warm, full-bodied sound, excellent soundstaging, and dynamic performance, suitable for both large and smaller listening rooms. The design is described as simple yet elegant, with a satin-black finish and no front or rear grilles by default. The price is around per pair, with some listings showing prices near with upgrade packages. The speaker is highly regarded for its audiophile attributes and innovative approach to open-baffle speaker design.