JBL 125A
Thiele-Small parameters
| Nominal size | 12" |
|---|---|
| Impedance | 8 Ω |
| Fs | 25 Hz |
| Qts | 0.433 |
| Qes | 0.46 |
| Qms | 7.5 |
| Vas | 235 L |
| Sd | 486.5 cm² |
| Xmax | 4.8 mm |
| Re | 5.2 Ω |
| Bl | 10.1 T·m |
| Mms | 57.2 g |
| Pe | 50 W |
| Sensitivity | 92.9 dB |
Alignment hint
| EBP | 54 · flexible |
|---|---|
| Sealed Vb (Qtc ≈ 0.71) | ≈ 141 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 |
|---|---|---|---|---|---|---|---|---|
| JBL 127A | 25 = | 0.433 = | 235 = | 4.8 = | 92.9 = | close | + | |
| JBL 2213 | 25 = | 0.49 +0.06 | 235 = | 6.8 +2 | 93.1 +0.2 | close | + | |
| Audax PR300M0 vp AP | 26.9 +1.9 | 0.448 +0.02 | 231 -4 | 4.4 -0.4 | 92.2 -0.7 | close | Xmax 4.4 mm < 4.8 mm: lower excursion-limited SPL | + |
| JBL 123A | 25 = | 0.49 +0.06 | 235 = | 7.9 +3.1 | 93.1 +0.2 | close | + | |
| JBL 2213H | 25 = | 0.49 +0.06 | 235 = | 7.9 +3.1 | 93.1 +0.2 | close | + | |
| Peerless 315SWR | 24 -1 | 0.433 = | 210 -25 | 8 +3.2 | 91.3 -1.6 | close | + | |
| Peerless 831857 | 24 -1 | 0.433 = | 210 -25 | 9 +4.2 | 91.3 -1.6 | close | + | |
| Peerless SLS315 | 24.4 -0.6 | 0.452 +0.02 | 205.2 -29.8 | 7.8 +3 | 91.4 -1.5 | close | + | |
| SB Acoustics SB34NRX75-6 vp | 22.2 -2.8 | 0.444 +0.01 | 240 +5 | 11 +6.2 | 92 -0.9 | close | + | |
| Philips AD12250W8 vp doum1 | 29.5 +4.5 | 0.404 -0.03 | 216 -19 | 6 +1.2 | 93.2 +0.3 | close | + |
Compare the closest 3 against the 125A →
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.