Suggestions and help for my Air 540 fan setup?

[ThomasD]

4 minutes ago, WoodenMarker said:

The motor or bearing is usually what makes more noise than airflow. If you think airflow is what you're hearing more of, you're probably referring to turbulence. 

The primary noise difference between AF120's and SP120's aren't due to the blade design.

Motor and bearing, along with other things like frame and blade vibration would all fall under the heading of 'fan movement.'  That's what dampeners and rubber mounts are supposed to reduce.

 

But yeah, I do tend to think most fan noise comes from air movement (of which turbulence is only part.)

 

And yes, the noise as well as pressure performance differences between AF and SP type fans are directly related to blade design.  It is the primary reason the two fan types perform differently.  This should be even more obvious when looking at the Corsairs - since all four version use the exact same frame.  The blades are the biggest difference between them.

 

Again, I'll repeat - you cannot extrapolate comparisons between the AF fans to a comparison between the SP fans.  That is apples to oranges.

 

 

[WoodenMarker]

8 minutes ago, ThomasD said:

Motor and bearing, along with other things like frame and blade vibration would all fall under the heading of 'fan movement.'  That's what dampeners and rubber mounts are supposed to reduce.

But yeah, I do tend to think most fan noise comes from air movement (of which turbulence is only part.)

Again, I'll repeat - you cannot extrapolate comparisons between the AF fans to a comparison between the SP fans.  That is apples to oranges.

Laminar flow is silent. All airflow noise is turbulence and fan frames/blade design cause very little noise from turbulence compared to the motor/bearing for the majority of case fans that aren't the quietest like Noctuas or BeQuiets! If most of the noise you hear is from your airflow, you either have a grill or some other sort of obstruction that's causing it. 

I've personally compared SP120 PE and QE's and I hear a difference. 

Your assertion of PE's and QE's performing/sounding the same seems to be speculation so I'll ask again. do they sound the same to you?

[ThomasD]

1 minute ago, WoodenMarker said:

Laminar flow is silent. All airflow noise is turbulence and fan frames/blade design cause very little noise from turbulence compared to the motor/bearing for the majority of case fans that aren't the quietest liek Noctuas or BeQuiets! If most of the noise you hear is from your airflow, you either have a grill or some other sort of obstruction that's causing it. 

I've personally compared SP120 PE and QE's and I hear a difference. 

Laminar flow is theoretically silent.  You are talking to someone who works within a laminar flow hood.  It is not silent in practice, and for a number of reasons - a big one being friction. 

 

Nor is any case fan remotely laminar in flow characteristics.  They are all radial fans after all

 

The Performance editions can be run as quietly as the Quiet editions if you are willing to play with fan curves.  The Quiet editions can never move as much air as the Performance editions.

 

 

[WoodenMarker]

11 minutes ago, ThomasD said:

The Performance editions can be run as quietly as the Quiet editions if you are willing to play with fan curves.  The Quiet editions can never move as much air as the Performance editions.

PE's can't get as quiet as QE's can. At the same voltage, QE's run at a lower rpm and they both take a similar amount of voltage to start spinning. 

 

Exerpt from the SPCR article:

Quote

We also had two samples of the Performance Edition of the SP120 but we deemed both to be poor candidates for a quiet system and unworthy of a full test run-down. A cursory examination revealed an odd little flutter (as if the motor was slightly off balance) at 1,500 RPM not present in the Quiet Edition, and at 900 RPM it had more pronounced tonal elements.

 

[Heesleemer]

40 minutes ago, ThomasD said:

Unpossible.  Unless you think that noise comes from something other than air movement and fan movement.  Identical physical objects performing in an identical manner (within the limits of measurement) will yield identical observable effects (within the limits of measurement.)

 

And yeah, I noted after I posted that you changed the subject to AF fans, which we were not previously talking about.  But you still cannot extrapolate that AF comparison to an SP comparison because the AF fans are physically different from the SP fans (different blade number and shape.)

 

You still have no evidence for comparing SP PE to SP QE.

Do you know how motors work? 
 

[ThomasD]

18 hours ago, Heesleemer said:

Do you know how motors work? 
 

Yeah I know how motors work.  You do know that any motor noise would fall under 'fan movement?'  Unless you somehow thing the motor is either not part of the fan or doesn't move.

[ThomasD]

19 hours ago, WoodenMarker said:

PE's can't get as quiet as QE's can. At the same voltage, QE's run at a lower rpm and they both take a similar amount of voltage to start spinning. 

 

Exerpt from the SPCR article:

 

Again, that is just subjective opinion.

 

You still have no data to back up your opinion.

 

This is pointless, you are going to keep insisting something that objectively makes no sense.  Both fans use the same blades and the same frame.  The idea that both spinning at the same RPM would somehow yield different results defies logic and reason.

[WoodenMarker]

2 hours ago, ThomasD said:

Again, that is just subjective opinion.

 

You still have no data to back up your opinion.

 

This is pointless, you are going to keep insisting something that objectively makes no sense.  Both fans use the same blades and the same frame.  The idea that both spinning at the same RPM would somehow yield different results defies logic and reason.

Fans have something called a starting voltage. At that starting voltage, PE's and QE's have a different rpm. PE's can't spin as slowly as QE's can. 

Fan noise is subjective to a degree and it seems like you're speaking from speculation whereas we're speaking from experience. 

We don't know for certain if what's inside of the fan is the same between the two versions so do not assume that they are.