Onkyo SCEPTER 10 (circa 1976)

A large-scale floor-type speaker system using a 38 cm woofer and horn-type tweeter with acoustic lens.

Overview

Specifications

Model Rating Method	2-Way, 2-Speaker, Bass Reflex System, Floor Type
Units Used	For Low Band: 38 cm cone type (W-3810A); For High Range: Horn type (TW-1206A + Acoustic Lens AL-120)
Playback frequency band	30 Hz to 20 kHz
Max Input	100W
Impedance	8 Ω
Output sound pressure	95dB/W/m
Cabinet internal volume	160L
Selector	3-step mode selector
External dimensions	Width 560 mm x Height 869 mm x Depth 522 mm
Weight	44 kg

Design

The SCEPTER 10 uses a 38 cm cone woofer (W-3810A) with a multi-corrugation cone, a 78 mm diameter long voice coil with heat-resistant design, and an aluminum reinforcing ring at the cone/voice coil joint. The woofer features a specially molded 2-layer urethane foam edge and a butterfly damper made of heat-resistant resin laminate. Its magnetic circuit includes a 180 mm x 95 mm x 20 mm magnet with an H-type pole piece and a copper short ring to reduce harmonic distortion. The tweeter is a horn-type (TW-1206A) with a 20 micron titanium foil diaphragm and an aluminum die-cast short horn with a 500 Hz cutoff frequency, paired with an AL-120 acoustic lens made from high-impact styrene polymers to prevent blade sticking. The cabinet baffle is constructed from 20-mm Yonematsu plate, with softwood chip board sides and internal reinforcement. The exterior has a rosewood grain finish.