Choose Dreo DR-HAP009S if you want lower noise.
Which purifier has higher CADR?
Alen 45i has published CADR; Dreo DR-HAP009S does not.
Which purifier is quieter?
Dreo DR-HAP009S is quieter (18 vs 23 dB).
Which purifier covers a larger room?
Alen 45i is recommended for about 395 sq ft based on CADR.
Which purifier has better smart features?
Both list smart features (True HEPA filtration, Whisper-quiet operation, Smart Sensor, Auto Mode vs Wi‑Fi/Voice/Alexa control, HEPA Sleep Mode, Air Quality Monitor, PM2.5 Monitor).
Which purifier has better filtration?
Alen 45i lists HEPA; Dreo DR-HAP009S lists 3-in-1 HEPA Filter (Pre-filter, HEPA, Activated Carbon).
Bottom line
Choose Dreo DR-HAP009S if you want lower noise.
| Metric | Alen 45i | Dreo DR-HAP009S | Difference / Winner |
|---|---|---|---|
| Smoke CADR | 255 CFM | — | — |
| Recommended room size | 395 sq ft | — | — |
| Manufacturer claimed coverage | 1900 sq ft | 1176 sq ft | — |
| Minimum noise | 23 dB | 18 dB | Dreo DR-HAP009S |
| Filter type | HEPA | 3-in-1 HEPA Filter (Pre-filter, HEPA, Activated Carbon) | — |
| Wi-Fi / app | Yes | Yes | — |
| Weight | 14 lb | 6.9 lb | — |