The Soundtube's HP129a-WH is a 12-inch, Hi-Power Coaxial Open-
Ceiling Speaker plus a surface-mount option as well as a
proprietary BroadBeamHP® wave-guide. The HP129a delivers real
high-SPL performance thereby incorporating a 12-inch treated
fiber cone and a single 35 mm (1.38 inches) Mylar compression
driver with an advanced-grade electro-acoustic subassembly.
It leads to a pendant-mount speaker with maximum
effectiveness (97 dB 1W/1M) and an extensive frequency
response starting from 73 Hz to 19 kHz (-10 dB). For long-
lasting performance, the enclosure has injection-molded,
For surface-mount applications, HP129a-WH provides a surface
mount adaptor (AC-HP-SM129).