Sine Design

SB Acoustics SB15NRX2C30-8

woofer · EBP 99 → suits either box · nominal (full) — SB Acoustics datasheet (https://sbacoustics.com/wp-content/uploads/2020/02/5in-SB15NRX2C30-8.pdf)

Thiele/Small parameters

Fs (resonance)36.5 Hz
Qts0.34
Qes / Qms0.37 / 3.48
Vas20.0 L
Re / nominal Z— / 8 Ω
Xmax
Sensitivity86.0 dB (1 W/1 m, calc); 86.5 dB (2.83 V/1 m, mfr)
Power handling50 W

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

Datasheet (PDF) ↗ — manufacturer-hosted

Recommended enclosures

Sealed (Qtc 0.707) — Vb6.0 L
Sealed — Fc / F375.9 / 75.9 Hz
Ported (suggested) — Vb11.4 L
Ported — Fb / F343.5 / 45.8 Hz

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About this driver

The SB Acoustics SB15NRX2C30-8 is a woofer with a free-air resonance of 36.5 Hz and a total Q (Qts) of 0.34. Its efficiency-bandwidth product (EBP) of 99 points toward either alignment. In a 6.0 L sealed box it reaches an F3 of 75.9 Hz (Qtc 0.707); a suggested 11.4 L box tuned to 43.5 Hz extends to about 45.8 Hz. See the sealed vs ported guide for how to choose.

Recommended partners

modeled estimate

These tweeters could pair with the SB Acoustics SB15NRX2C30-8 in a two-way design, but the seed Thiele/Small data is too thin to grade the match yet — add or measure T/S (Fs, Sd, Xmax) to compute a real compatibility grade. You can still open a pair in the guided builder.

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

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