Ported 2-way tower — dual Scan-Speak 18W + SB29 ring radiator
2× Scan-Speak 18W/8531G00 + SB Acoustics SB29RDC-C000-4 · 70 L ported box tuned to 30 Hz · 2-way Linkwitz-Riley 4th-order at 2.2 kHz
Drivers
- WooferScan-Speak 18W/8531G00×28 Ω · Fs 28 Hz
- TweeterSB Acoustics SB29RDC-C000-4×14 Ω · Fs 600 Hz
Crossover
| Type | Linkwitz-Riley |
| Slope | 24 dB/oct (4th order) |
| Crossover point | 2.2 kHz |
Tune component values in the crossover designer.
Compatibility check
1 warningThis recipe passes the Sine Design compatibility engine with no errors — the enclosure alignment and crossover are sensible for these drivers. Notes below are informational.
About this design
A floorstanding 2.5/2-way using two Scan-Speak 18W/8531G00 Revelator midwoofers in a 70 L vented box tuned to 30 Hz (twin 7 cm ports keep port velocity in check). The SB29RDC ring-radiator crosses in at 2.2 kHz on LR4. Two 8 Ω woofers wired in parallel present a nominal 4 Ω woofer load — pair with an amp comfortable into 4 Ω. Published Scan-Speak T/S are nominal; measure before finalising the box.
Want to change a driver, the box size or the crossover point? Open this recipe in the builder — every slot is pre-filled, and the live compatibility check follows your edits. Published Thiele/Small parameters are nominal; measure your drivers (DATS/REW) and model the final cabinet before building.
Estimated parts list
| Part | Qty | Est. | Buy |
|---|---|---|---|
| Scan-Speak 18W/8531G00 | 2 | — | Parts Express → |
| SB Acoustics SB29RDC-C000-4 | 1 | — | Parts Express → |
| 1 mH air-core inductor (L3 series) | 1 | $6 | Parts Express → |
| 15 µF film capacitor (C3 shunt) | 1 | $3 | Parts Express → |
| 0.47 mH air-core inductor (L4 series) | 1 | $6 | Parts Express → |
| 3.3 µF film capacitor (C4 shunt) | 1 | $3 | Parts Express → |
| 10 µF film capacitor (C1 series) | 1 | $3 | Parts Express → |
| 0.15 mH air-core inductor (L1 shunt) | 1 | $6 | Parts Express → |
| 18 µF film capacitor (C2 series) | 1 | $3 | Parts Express → |
| 0.68 mH air-core inductor (L2 shunt) | 1 | $6 | Parts Express → |
| Binding-post terminal cup | 1 | $6 | Parts Express → |
| Acoustic damping / polyfill (~700 g) | 1 | $9 | Parts Express → |
| Port tube / flare ×1 | 1 | $8 | Parts Express → |
| Cabinet panel stock (MDF/ply) for ~70 L net | 1 | $45 | local |
| Fasteners, gasket & sealant | 1 | $6 | local |
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