Results: frequency response of sound
Why do cases and PSUs almost always have impractical cut-outs in the grille in front of fans for air passage? Whether this is due to indifference to an all-round honest product or ignorance of how inefficient a solution it is, remains a mystery. But we have devised a comparative test which refers to drawbacks of the hexagonal grille. Compared to the non-restrictive circular ones made of wires, the differences are significant.
Sound colour
Type of obstacle | Dominant sound freq. and noise level, Noctua NF-A12x25 PWM@7 V | NF-F12 PWM | NF-A15 PWM | ||||
Low range | Mid range | High range | |||||
Frequency [Hz] | Noise level [dBu] | Frequency [Hz] | Noise level [dBu] | Frequency [Hz] | Noise level [dBu] | ||
Hexagonal grille | Hexagonal grid | 126,992 | -77,806 | 339,028 | -69,128 | 1974,030 | -89,846 |
Circular grille | 20,306 | -76,419 | 201,587 | -69,415 | 18780,243 | -90,922 | |
Plastic dust filter | 126,992 | -68,642 | 339,028 | -74,269 | 5583,400 | -89,100 | |
Nylon dust filter | Nylon dust filter | 195,849 | -63,331 | 201,587 | -62,790 | 1974,030 | -90,464 |
No obstacle | Plastic dust filter | 130,713 | -77,289 | 339,028 | -74,287 | 1974,030 | -90,361 |
- Contents
- The grille must also be aerodynamic
- Results: impact on airflow, pressure and noise
- Results: frequency response of sound
- Be fastidious, demand effective shapes