P.Audio IMF HP-21W
Thiele-Small parameters
| Nominal size | 21.5" |
|---|---|
| Impedance | 8 Ω |
| Fs | 36.4 Hz |
| Qts | 0.463 |
| Qes | 0.52 |
| Qms | 4.22 |
| Vas | 384.4 L |
| Sd | 1661 cm² |
| Xmax | 6.6 mm |
| Re | 5.5 Ω |
| Bl | 21.6 T·m |
| Mms | 192.3 g |
| Pe | 850 W |
| Sensitivity | 99.1 dB |
Alignment hint
| EBP | 70 · flexible |
|---|---|
| Sealed Vb (Qtc ≈ 0.71) | ≈ 288.5 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 |
|---|---|---|---|---|---|---|---|---|
| Beyma 21L50 | 33 -3.4 | 0.434 -0.03 | 300 -84.4 | 7.9 +1.3 | 97 -2.1 | usable | + | |
| MC Kenzie FRL-21/1200-LF | 30 -6.4 | 0.378 -0.09 | 374 -10.4 | 9.5 +2.9 | 98 -1.1 | usable | + | |
| RCF LF 21N401 | 30 -6.4 | 0.378 -0.09 | 374 -10.4 | 10.6 +4 | 98 -1.1 | usable | + | |
| SICA 21 S 4 PL | 38.7 +2.3 | 0.431 -0.03 | 229.8 -154.6 | 6.4 -0.2 | 100 +0.9 | usable | 4 Ω vs 8 Ω: amp load changes · Xmax 6.4 mm < 6.6 mm: lower excursion-limited SPL | + |
| B&C 21 SW 115 | 32.5 -3.9 | 0.404 -0.06 | 268.7 -115.7 | 9.9 +3.3 | 99.2 +0.1 | usable | 4 Ω vs 8 Ω: amp load changes | + |
| Beyma 21PW1400FE | 30 -6.4 | 0.343 -0.12 | 401.5 +17.1 | 10 +3.4 | 98.6 -0.5 | usable | + | |
| SB Audience NERO-21SW1100D | 32 -4.4 | 0.339 -0.12 | 312.6 -71.8 | 8.1 +1.5 | 98.6 -0.5 | usable | + | |
| Beyma 21SW1600ND | 33 -3.4 | 0.382 -0.08 | 268 -116.4 | 8.9 +2.3 | 97.6 -1.5 | usable | + | |
| RCF LF 21X451 | 28 -8.4 | 0.369 -0.09 | 385 +0.6 | 13 +6.4 | 97 -2.1 | usable | + | |
| LaVoce SAF214.50 vp | 30 -6.4 | 0.401 -0.06 | 311 -73.4 | 11.6 +5 | 96.4 -2.7 | usable | + |
Compare the closest 3 against the IMF HP-21W →
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.