RCF LF 21X451
Thiele-Small parameters
| Nominal size | 21.5" |
|---|---|
| Impedance | 8 Ω |
| Fs | 28 Hz |
| Qts | 0.369 |
| Qes | 0.39 |
| Qms | 6.9 |
| Vas | 385 L |
| Sd | 1700 cm² |
| Xmax | 13 mm |
| Re | 5.4 Ω |
| Bl | 28.8 T·m |
| Mms | 340 g |
| Pe | 2000 W |
| Sensitivity | 97 dB |
Alignment hint
| EBP | 72 · flexible |
|---|---|
| Sealed Vb (Qtc ≈ 0.71) | ≈ 144.1 L |
EBP 50-100: works in either a sealed or ported alignment.
Rules of thumb from T/S parameters only. Verify against a real simulation before cutting wood.
Substitute candidates
| Driver | Fs (Hz) | Qts | Vas (L) | Xmax (mm) | Sens (dB) | Fit | Notes | Compare |
|---|---|---|---|---|---|---|---|---|
| RCF LF 21N401 | 30 +2 | 0.378 +0.01 | 374 -11 | 10.6 -2.4 | 98 +1 | close | 1500 W vs 2000 W: lower power handling · Xmax 10.6 mm < 13 mm: lower excursion-limited SPL | + |
| MC Kenzie FRL-21/1200-LF | 30 +2 | 0.378 +0.01 | 374 -11 | 9.5 -3.5 | 98 +1 | close | 1200 W vs 2000 W: lower power handling · Xmax 9.5 mm < 13 mm: lower excursion-limited SPL | + |
| Beyma 21PW1400FE | 30 +2 | 0.343 -0.03 | 401.5 +16.5 | 10 -3 | 98.6 +1.6 | usable | 1400 W vs 2000 W: lower power handling · Xmax 10 mm < 13 mm: lower excursion-limited SPL | + |
| LaVoce SAF214.50 vp | 30 +2 | 0.401 +0.03 | 311 -74 | 11.6 -1.4 | 96.4 -0.6 | usable | Xmax 11.6 mm < 13 mm: lower excursion-limited SPL | + |
| 18 Sound 21NLW9000 | 29 +1 | 0.347 -0.02 | 304 -81 | 10.7 -2.3 | 96.4 -0.6 | usable | Xmax 10.7 mm < 13 mm: lower excursion-limited SPL | + |
| RCF 21LNW9000 | 29 +1 | 0.347 -0.02 | 304 -81 | 10.7 -2.3 | 96.4 -0.6 | usable | Xmax 10.7 mm < 13 mm: lower excursion-limited SPL | + |
| LaVoce SAF214.50 | 30 +2 | 0.435 +0.07 | 267 -118 | 11.6 -1.4 | 95.6 -1.4 | usable | Xmax 11.6 mm < 13 mm: lower excursion-limited SPL | + |
| Ciare NDC 21-5 | 32.2 +4.2 | 0.344 -0.03 | 270.8 -114.2 | 8.8 -4.2 | 97.2 +0.2 | usable | 1500 W vs 2000 W: lower power handling · Xmax 8.8 mm < 13 mm: lower excursion-limited SPL | + |
| Beyma 21SW1600ND | 33 +5 | 0.382 +0.01 | 268 -117 | 8.9 -4.1 | 97.6 +0.6 | usable | Xmax 8.9 mm < 13 mm: lower excursion-limited SPL | + |
| SB Audience NERO-21SW1100D | 32 +4 | 0.339 -0.03 | 312.6 -72.4 | 8.1 -4.9 | 98.6 +1.6 | usable | 1100 W vs 2000 W: lower power handling · Xmax 8.1 mm < 13 mm: lower excursion-limited SPL | + |
Compare the closest 3 against the LF 21X451 →
Ranked on parameter similarity only (Qts, Fs, Vas, Xmax, sensitivity). Same nominal size required. A hint, not a simulation, model the swap before cutting or buying.
Used in enclosures (0)
No enclosure in the catalog uses this driver yet.