Sine Design

Eminence ALPHA-8MRA

woofer · EBP 247 → suits a ported box · nominal (full) — Eminence datasheet (https://cdn.shopify.com/s/files/1/0270/8665/1462/files/Alpha_8MRA.pdf)

Thiele/Small parameters

Fs (resonance)514 Hz
Qts1.42
Qes / Qms2.08 / 4.48
Vas0.8 L
Re / nominal Z7.32 Ω / 8 Ω
Xmax1.6 mm
Sensitivity99.3 dB (1 W/1 m, calc); 100.9 dB (2.83 V/1 m, mfr)

Published (nominal) values, params full — verify by measurement (DATS/REW) before building.

Datasheet (PDF) ↗ — manufacturer-hosted

Recommended enclosures

Sealed (Qtc 0.707) — VbInfinity L
Sealed — Fc / F3514.0 / 363.2 Hz
Ported (suggested) — Vb54.0 L
Ported — Fb / F3141.9 / 339.4 Hz

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About this driver

The Eminence ALPHA-8MRA is a 8″ woofer with a free-air resonance of 514 Hz and a total Q (Qts) of 1.42. Its efficiency-bandwidth product (EBP) of 247 points toward a ported alignment. In a Infinity L sealed box it reaches an F3 of 363.2 Hz (Qtc 0.707); a suggested 54.0 L box tuned to 141.9 Hz extends to about 339.4 Hz. See the sealed vs ported guide for how to choose.

Recommended partners

modeled estimate

The tweeters below pair well with the Eminence ALPHA-8MRA 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.

Modeled estimate from T/S + geometry — no measurements. The verdict is robust; it improves with measured FRD/ZMA data.

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