JBL 2121
Thiele-Small parameters
| Nominal size | 10" |
|---|---|
| Impedance | 8 Ω |
| Fs | 35 Hz |
| Qts | 0.193 |
| Qes | 0.2 |
| Qms | 5.5 |
| Vas | 110.4 L |
| Sd | 316.1 cm² |
| Xmax | 1.5 mm |
| Re | 6.8 Ω |
| Bl | 14 T·m |
| Mms | 26.2 g |
| Pe | 50 W |
| Sensitivity | 96.4 dB |
Alignment hint
| EBP | 175 · ported |
|---|---|
| Sealed Vb (Qtc ≈ 0.71) | ≈ 8.9 L |
EBP > 100: favours a ported (bass-reflex) 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 |
|---|---|---|---|---|---|---|---|---|
| JBL 2121H | 35 = | 0.165 -0.03 | 110.4 = | 1.5 = | 97.7 +1.3 | close | + | |
| Klipsch K1089-AV | 31 -4 | 0.216 +0.02 | 106.2 -4.2 | 4.4 +2.9 | 94.8 -1.6 | usable | + | |
| Conrad DS-100i | 22.5 -12.5 | 0.188 -0.01 | 112.2 +1.8 | 1.5 = | 93.6 -2.8 | usable | 4 Ω vs 8 Ω: amp load changes | + |
| Audax HIF24HS | 33.6 -1.4 | 0.274 +0.08 | 117 +6.6 | 3.5 +2 | 94.9 -1.5 | usable | 30 W vs 50 W: lower power handling | + |
| David Eden EC1060XS8 | 39 +4 | 0.18 -0.01 | 78 -32.4 | 4.3 +2.8 | 99 +2.6 | usable | 4 Ω vs 8 Ω: amp load changes | + |
| Fostex FW 220 | 29 -6 | 0.195 = | 76 -34.4 | 3.7 +2.2 | 92.5 -3.9 | usable | + | |
| Audio Nirvana SUPER CAST FRAME 10 | 34 -1 | 0.254 +0.06 | 173 +62.6 | 3 +1.5 | 96.4 = | usable | 30 W vs 50 W: lower power handling | + |
| JBL LE111A | 25 -10 | 0.175 -0.02 | 101.9 -8.5 | 4.8 +3.3 | 92.9 -3.5 | usable | + | |
| Focal 10C 012-DB | 26.3 -8.7 | 0.238 +0.04 | 134.7 +24.3 | 2.5 +1 | 93.8 -2.6 | usable | + | |
| Eminence DELTALITE 2510 | 41.2 +6.2 | 0.295 +0.1 | 107.9 -2.5 | 4.2 +2.7 | 97.5 +1.1 | usable | + |
Compare the closest 3 against the 2121 →
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.