Noise Measurements

[crmaris]

Very soon I will built a small anechoic chamber to test really quiet PSUs and also I plan to push noise measurements to another level. Here is a teaser, since I just finished the relevant code and made the necessary modifications to my equipment

[bobnova]

That will be very cool to see. I look forward to it.
I'd like to see the NEX1500's numbers :P

[crmaris]

unfortunately I don't have it (they took it back) but even if I did no time for old units to be re-tested.. Lots of extra activities lately

[Philipus II]

When are you going to show us some pictures?

[crmaris]

once I have all materials in hand and build my mini anechoic chamber since I decided to use one for extended noise measurements (currently I can only measure noise over 30-32dBA)
Also I decided to enrich my noise measurements equipment and now I am working on the program that will control the PSU's fan (through an external bench programmable PSU) and the db meter.

[crmaris]

these programmable bench PSUs are damn expensive. They ask for over 300 euros for a plain 200W bench PSU. My pocket will hurt again but this isn't a showstopper for me..

[crmaris]

some of the needed materials just arrived

[Philipus II]

Interesting concept.
You are going to measure the PSU fan Speed/fan voltage with the Chroma loads. Later you will use the same voltage provided by a programmable PSU to spin the fan without the PSU switched on, am I right?

Thought about that, too, but I decided to go for real PC-systems. During noise testing I will stop all fans, so it should work.

I'm really interested if your anechoic chamber really works. The be quiet! kits should be decent quality and they are easy to get.

[crmaris]

Yeap Philip in general this is the main concept. A real PC-system needs to be installed in a damn silent environment to get readings below 30dBA and also even the slightest noise from the system will alter the readings, and we are interested only in the noise of the PSU.

As for programmable PSU I plan to test the whole fan operational area and not only the values I measured through my tests. Although in my auto crossload tests I run thousand of tests and I have to replicate all of them. For this a program is needed that will control both the db meter and the PSU, gather the data and save it. Afterwards this data will be analyzed by another program that I wrote and the result will be the graph shown at post #1. It needs lots of work to be done but I am sure that the result will definitely worth it.

[bobnova]

That sounds like a pain! I'm very much looking forward to the results though.