681A
| Brand | Altec Lansing, Altec |
| Manufacturer | LTV Ling Altec, Inc. |
| Function | Microphone |
| Country | United States |
| Form Factor | Handheld / Stand Mounted |
| Signal Path | Passive Hardware |
| Dimensions | 2.8 × 2.8 × 18.8 cm (W × H × D) |
| Weight | 0.6lbs |
| Frequency Response | 50Hz-18kHz |
| Element Type | Moving Coil Dynamic |
| Directivity Pattern | Omnidirectional |
| Output Impedance | 150/250Ω, 20kΩ (Specified at order) |
| Output Level | -55dBm/10dynes/cm² |
| Hum (Ref. 10⁻³ Gauss) | -120dB |
| Finish | Dark Green, Brushed Chrome (Optional: 22-carat Gold plate) |