820C
| Brand | Altec |
| Manufacturer | Altec Lansing Corporation |
| Function | Speaker |
| Produced | 1955-195? |
| Country | United States |
| Form Factor | Floorstanding |
| Signal Path | Passive Hardware |
| Dimensions | 107.3 × 120.4 × 73.7 cm (W × H × D) |
| Weight | 230lbs (Shipping) |
| Frequency Response | 30Hz-22kHz |
| Treble | 8.6"x18.4" Sectoral Horn (Altec 811B, Altec 802C) |
| Midrange/Bass | 15" Paper Cone (x2) (Altec 803A) |
| Impedance (Nominal) | 16Ω |
| Crossover Frequency | 800Hz (Altec N-800D) |
| Dispersion (Horizontal) | 90° |
| Dispersion (Vertical) | 40° |
| Power Handling | 30W |
| Enclosure Type | Front-loaded Horn, Bass Reflex (Altec 821A) |
| Finish | Mahogany Blond |
| MSRP (1956) | $525 |