MP 4
| Brand | Martin Persson |
| Manufacturer | Ingenjörsfirma Martin Persson* |
| Function | Speaker |
| Produced | 1965 |
| Country | Sweden |
| Form Factor | Bookshelf / Stand Mounted |
| Signal Path | Passive Hardware |
| Dimensions | 41 × 62 × 16.5 cm (W × H × D) |
| Frequency Response | 45Hz-16kHz |
| Impedance (Nominal) | 4Ω, 8Ω, 16Ω (Selected at purchase) |
| Power Handling | 12W |