RTA (measurement system)

[guru_jeff]

My place of work is looking for a measurement system similar to the systems that are used for loudspeaker measurements. I have another post that I put up hear looking for what type of mic, preamp and software to use for my home loudspeaker measurement system and I assume they can be used as an RTA as well.

Please give me some feedback or other suggestions for some equipment to use. We do have a budget but it is more than my home budget.

This is what we are looking at right now.

RTA Link

We are using it to measure the noise output on some brushed DC motors with gearboxes. They are being measured in a sound box that was put together with foam insulation material.

My other thought would be something like PC RTA from Linear X
PCRTA

 

[joe carrow]

I remember that Cool Edit Pro (before it was bought by Adobe and turned into Audition) had some good analysis tools. I don't know if they made it into Audition, and I don't know if you can still pick up a copy of Cool Edit, but my main point is that you might not really need real time analysis.

If you're just measuring relative tweaks to a motor to see how they affect noise output, and you're not trying to come up with some sort of real-time control system, then taking a snapshot of the noise and post-processing it could be a cheap way to get 'er done.

EDIT: Check out Audacity (download.com) . It's free, and although I haven't tried it yet it looks like it can do some useful analysis.

 

[guru_jeff]

The RTA would be helpful because we will probably change motor RPM and or loading while it is being tested and it would save a lot of time instead of taking a sample at various data points.

 

[bwaslo]

PRAXIS at libinst.com can be used (in its demo/free mode) as a free RTA and pink noise generator, as narrow as 1/48th octave.

 

[guru_jeff]

How much does Praxis cost? I know you can get the free demo version. I heard they have a calibrated mic with the Aud pod package. How much is that? I sent an email to them but haven't heard back.
Any thoughts? Anyone purchased these before?

 

[owdi]

I remember that Cool Edit Pro (before it was bought by Adobe and turned into Audition) had some good analysis tools. I don't know if they made it into Audition, and I don't know if you can still pick up a copy of Cool Edit, but my main point is that you might not really need real time analysis.

If you're just measuring relative tweaks to a motor to see how they affect noise output, and you're not trying to come up with some sort of real-time control system, then taking a snapshot of the noise and post-processing it could be a cheap way to get 'er done.

EDIT: Check out Audacity (download.com) . It's free, and although I haven't tried it yet it looks like it can do some useful analysis.

The waveform analysis in Audacity is pretty useless. You can't zoom or change scale, and the values shown on the x axis don't match the displayed chart very well.

Dan

 

[guru_jeff]

I'm not looking at Audacity because I haven't heard too much about them. I'm looking at Praxis, possibly ARTA and audio tester.

Thank you