Great Plains Audio 3127 GPA
Thiele-Small parameters
| Nominal size | 12" |
|---|---|
| Impedance | 8 Ω |
| Fs | 50 Hz |
| Qts | 0.219 |
| Qes | 0.26 |
| Qms | 1.37 |
| Vas | 70.8 L |
| Sd | 506.5 cm² |
| Xmax | 3.4 mm |
| Re | 6.4 Ω |
| Bl | 19.9 T·m |
| Mms | 51.5 g |
| Pe | 250 W |
| Sensitivity | 98.3 dB |
Alignment hint
| EBP | 192 · ported |
|---|---|
| Sealed Vb (Qtc ≈ 0.71) | ≈ 7.5 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 |
|---|---|---|---|---|---|---|---|---|
| Altec 3127 | 50 = | 0.219 = | 70.8 = | 3.4 = | 98.3 = | close | + | |
| P.Audio BM-12CX38 | 48 -2 | 0.221 = | 72.9 +2.1 | 4.5 +1.1 | 99.3 +1 | close | + | |
| 18 Sound 12ND930 | 50 = | 0.21 -0.01 | 70 -0.8 | 6.5 +3.1 | 98 -0.3 | close | + | |
| RCF L 12N301 | 48 -2 | 0.213 -0.01 | 70 -0.8 | 5 +1.6 | 99.1 +0.8 | close | + | |
| B&C 12PLB76 | 50 = | 0.23 +0.01 | 75 +4.2 | 5 +1.6 | 99 +0.7 | close | + | |
| B&C 12 PLB 76 | 50 = | 0.229 +0.01 | 75 +4.2 | 4.4 +1 | 99.7 +1.4 | close | + | |
| PHL Audio 4070 | 47 -3 | 0.207 -0.01 | 68 -2.8 | 4.6 +1.2 | 98.7 +0.4 | close | + | |
| BMS 12N610 | 44.7 -5.3 | 0.227 +0.01 | 67.6 -3.2 | 3.5 +0.1 | 97.5 -0.8 | close | + | |
| B&C 12 CXN 88 | 50 = | 0.224 +0.01 | 59 -11.8 | 4 +0.6 | 99.1 +0.8 | close | + | |
| P.Audio C12-500MB | 47 -3 | 0.238 +0.02 | 73 +2.2 | 4.5 +1.1 | 98 -0.3 | close | + |
Compare the closest 3 against the 3127 GPA →
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.