Model Twenty-Eight
| Brand | KLH |
| Manufacturer | KLH Research & Development Corp. |
| Function | Speaker |
| Produced | 1974 |
| Country | United States |
| Form Factor | Floorstanding / Stand Mounted |
| Signal Path | Passive Hardware |
| Dimensions | 64.8 × 46 × 40.9 cm (W × H × D) |
| Weight | 85lbs (Shipped) |
| Treble | 1.75" Paper Cone |
| Treble (Rear) | 1.75" Paper Cone (x2) |
| Midrange/Bass | 10" Paper Cone |
| Midrange/Bass (Rear) | 10" Paper Cone (x2) |
| Impedance (Nominal) | 8Ω |
| Crossover Frequency | 1.5kHz |
| Dispersion | 360° ("Omnireflective") |
| Recommended Amplifier Power | >30W |
| Power Handling | 400W |
| Enclosure Type | Sealed |
| Enclosure Resonance | 36Hz |
| Finish | Walnut |
| MSRP (1974) | $299.95 (With Pedestal) |