Seas CA18RNX H1215-08
woofer · EBP 95 → suits either box · nominal (full) — Seas CA18RNX H1215 datasheet (manufacturer)
Thiele/Small parameters
| Fs (resonance) | 35 Hz |
| Qts | 0.31 |
| Qes / Qms | 0.37 / 1.9 |
| Vas | 33.0 L |
| Re / nominal Z | 5.8 Ω / 8 Ω |
| Xmax | 6.0 mm |
| Sensitivity | 87.7 dB (1 W/1 m, calc); 88.5 dB (2.83 V/1 m, mfr) |
| Power handling | 250 W |
Published (nominal) values, params full — verify by measurement (DATS/REW) before building. datasheet
Recommended enclosures
| Sealed (Qtc 0.707) — Vb | 7.9 L |
| Sealed — Fc / F3 | 79.8 / 79.8 Hz |
| Ported (suggested) — Vb | 13.8 L |
| Ported — Fb / F3 | 45.8 / 50.4 Hz |
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About this driver
The Seas CA18RNX H1215-08 is a 6.5″ woofer with a free-air resonance of 35 Hz and a total Q (Qts) of 0.31. Its efficiency-bandwidth product (EBP) of 95 points toward either alignment. In a 7.9 L sealed box it reaches an F3 of 79.8 Hz (Qtc 0.707); a suggested 13.8 L box tuned to 45.8 Hz extends to about 50.4 Hz. See the sealed vs ported guide for how to choose.
NOMINAL/manufacturer (Seas Prestige datasheet). Fs 35 Hz; Vas 33 L; Sd 136 cm2; BL 7.2 Tm; Mms 14 g; sensitivity 88.5 dB (2.83V/1m); recommended range 45-3000 Hz; Xmax 6 mm (linear coil travel p-p 12 mm); short-term 250 W / long-term 80 W.
Recommended partners
modeled estimateThe tweeters below pair well with the Seas CA18RNX H1215-08 in a two-way design — each grade is a modeled estimate of the crossover match, with a suggested crossover point. Open any pair in the guided builder to design the crossover and total the parts.
- Seas 27TBFC/G H1212-06Good match· 93/100
Suggested crossover 1.25 kHz (4th-order, Linkwitz-Riley)
Build this pair → - Dayton Audio RS28F-4Good match· 92/100
Suggested crossover 1.25 kHz (4th-order, Linkwitz-Riley)
Build this pair → - SB Acoustics SB29RDC-C000-4Good match· 91/100
Suggested crossover 1.25 kHz (4th-order, Linkwitz-Riley)
Build this pair → - Peerless by Tymphany D27TG35-06Good match· 83/100
Suggested crossover 1.37 kHz (4th-order, Linkwitz-Riley)
Build this pair → - Dayton Audio ND25FA-4Moderate match· 50/100
Suggested crossover 2.02 kHz (4th-order, Linkwitz-Riley)
Build this pair →
Modeled estimate from T/S + geometry — no measurements. The verdict is robust; it improves with measured FRD/ZMA data.