Crossover Frequencies and Slopes
Table A.11: Recommended Crossover Points
| Speaker Type | High-Pass (Hz) | Low-Pass (Hz) | Typical Slope |
|---|---|---|---|
| Tweeters | 3,000-5,000 | - | 12-24 dB/oct |
| Midrange (small) | 500-800 | 4,000-7,000 | 12-18 dB/oct |
| Midrange (large) | 250-500 | 3,000-5,000 | 12-18 dB/oct |
| Midbass 6.5" | 60-80 | 300-500 | 12-24 dB/oct |
| Midbass 8" | 50-70 | 250-400 | 12-24 dB/oct |
| Subwoofer (sealed) | - | 80-120 | 12-24 dB/oct |
| Subwoofer (ported) | 25-35 (subsonic) | 80-100 | 24 dB/oct |
Table A.12: Crossover Slope Characteristics
| Slope | dB/octave | Order | Phase Shift | Overlap | Best Use |
|---|---|---|---|---|---|
| 1st Order | 6 dB/oct | Butterworth | 45° | High | Minimal filtering, time-aligned |
| 2nd Order | 12 dB/oct | Butterworth | 90° | Moderate | General purpose, common |
| 3rd Order | 18 dB/oct | Butterworth | 135° | Low | Better separation |
| 4th Order | 24 dB/oct | Linkwitz-Riley | 180° | Minimal | Clean separation, common |
| 6th Order | 36 dB/oct | Butterworth | 270° | Very Low | Maximum separation |
Note: Linkwitz-Riley 4th order sums to flat response when drivers are in phase.