Seas MR18REX-XF
tweeter · EBP 131 → suits a ported box · nominal (full) — Seas datasheet (https://www.seas.no/images/stories/prestige/pdfdatasheet/H1699_MR18REX_XF_Datasheet.pdf)
Thiele/Small parameters
| Fs (resonance) | 126 Hz |
| Qts | 0.69 |
| Qes / Qms | 0.96 / 2.49 |
| Vas | 3.0 L |
| Re / nominal Z | 6.2 Ω / 8 Ω |
| Xmax | — |
| Sensitivity | 89.8 dB (1 W/1 m, calc); 89 dB (2.83 V/1 m, mfr) |
| Power handling | 80 W |
Published (nominal) values, params full — verify by measurement (DATS/REW) before building.
Datasheet (PDF) ↗ — manufacturer-hosted
Recommended enclosures
This is a tweeter; Thiele/Small box parameters are not used for enclosure design.
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About this driver
The Seas MR18REX-XF is a 6″ tweeter with a free-air resonance of 126 Hz and a total Q (Qts) of 0.69. Its efficiency-bandwidth product (EBP) of 131 points toward a ported alignment. See the sealed vs ported guide for how to choose.
Recommended partners
modeled estimateThe woofers and midranges below pair well with the Seas MR18REX-XF 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 CA18RNX H1215-08Good match· 96/100
Suggested crossover 1.25 kHz (4th-order, Linkwitz-Riley)
Build this pair → - Peerless by Tymphany SLS-P830668Good match· 96/100
Suggested crossover 784 Hz (4th-order, Linkwitz-Riley)
Build this pair → - Peerless by Tymphany TC9FD18-08Good match· 96/100
Suggested crossover 2.42 kHz (4th-order, Linkwitz-Riley)
Build this pair → - Dayton Audio RS150T-8Good match· 93/100
Suggested crossover 1.58 kHz (4th-order, Linkwitz-Riley)
Build this pair → - Tang Band W5-1611SAFGood match· 93/100
Suggested crossover 1.51 kHz (4th-order, Linkwitz-Riley)
Build this pair → - Dayton Audio RS180-4Good match· 92/100
Suggested crossover 1.31 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.