Is a less than 4000 RPM option available?

Hi there!
I am a massive fan of digikey!

I have a fan model EFB1524VHG. I am wondering if there are models that are quieter?


There are options that do run quieter. However the the options that run at the lower end also have a lower overall air flow too.

There is a bit of variation between devices, but it can be seen that the nominal flow speed through a tubeaxial fan (CFM rating divided by frame area) is the dominant influence in the question. (see figure 2 here)

There may be opportunities for noise reduction by changing guards/filters or exhaust ports present, or if the existing unit is poorly-matched to the system, something with a different curve might offer improvement. But generally speaking, a larger fan is going to be quieter for a given flow rate.

Oh wow, thank you! This is super interesting. Do you know if they have the same wiring/molex connector? I think that 2100 RPM fan could be a great option.

Hi Rick_1976…your verbiage reminds me that I am utter noob when it comes to this. I have had to read through your paragraphs several times to attempt to understand everything you are saying.

That is interesting what you say about something with a different curve…do you mean the actual impellers? The fans are all attached to a metal plate and sit in a hollow roof to provide ventilation. I’d never even thought about the possibility of filters.

I’m going to attempt to attach sorbothane under the metal plate where it meets the wooden roof to attempt to reduce some of the dbs of vibration, but even as I type this I am thinking that perhaps that won’t do anything if the fan is just too loud for my customer.

There’s another resource describing fan and system curves here that will probably be found equally chewy, but hopefully informative/interesting…

But yes, to some extent a person may have options relating to the aerodynamics of a given fan; operation in or to the left of the “knee” of the fan curve as described there can result in more flow-generated noise than otherwise. A piece of clear tubing with some water and a ruler can be used to measure static pressure in a pinch, but it sounds as if you may have a situation that’s fairly low-pressure to start with.

Mechanical dampening may well help a bit, but if it’s that that hissing/white noise component of things caused by airflow itself that’s the problem, then a slower, lower-flow option would likely be the answer.

Thank you Rick!

Do all the fans come with standard wires and a variety of molex connectors? I’d love to get the quieter fans but am worried I won’t be able to connect them.

Thank you for all this guidance!

This page talks about that…

As you’ll see, the vast majority of fan products we carry have wire lead terminations; there’s no knowing what connector a customer will want to use or the arrangement of the different wires within, so that’s most often left up to the end user. Cutting the leads + connector off an existing device and splicing them onto a replacement is also a trick that’s been done on more than one occasion…

There are a handful of connectors that are popular for fans, referenced in this post. This other post mentions several common in the PC industry.

“Molex” proper is a major manufacturer of interconnect product with perhaps 100K different products listed under that banner alone, so “molex connector” on this side of the screen has a meaning about as specific as “General Mills food”. The more common ones people have in mind when using the term are likely referenced in the above posts, but more generally will be found classified as rectangular connectors: in general, connector products with built-in contacts will be listed as “connectors” (possibly “connector assemblies”) while those with separate contacts get classified as “housings” of a type (rectangular, circular, etc.) and the corresponding contacts classified under the corresponding “contacts” family.

It may not be immediately apparent, but there -is- a method underlying the madness…