Any suggestions for a audio spectrum adaptor for a scope ?

[gaetan8888]

Hello

Any suggestions for a very low cost audio spectrum analyser adaptor for an oscilloscope (diy or ready made) ?

Thank

Gaetan

[gofar99]

Greetings, Perhaps not exactly what you had in mind, but if you have a pc there are free programs that use the onboard soundcard (line in) to display audio spectrums. One I use is from Marchand Electronics (on the web) in their section of downloads. It does it in stereo too. Other programs are available for using pcs as scopes. A laptop works great.

Good listening
gofar99

[jackinnj]

The soundcard scopes will be more than adequate for most audio -- if you already have a scope there are lots of ideas on the web --

The HP3581 Wave Analyzer is usually available for under $100 -- this device has a great RMS detector, tracking generator and will measure down to the nanovolts at a few Hertz -- one of EBay's great gifts to DIYAUDIO land. If you replace the NiCads you can take it anywhere.

[gaetan8888]

Hello gofar99

I allready use a software with my sound card but it's not as good as a real spectrum analyser on a scope.

Thank

Gaetan

[gofar99]

Greetings Gaetan, Roger that.

Good listening
gofar99

[gaetan8888]

Originally posted by jackinnj
The soundcard scopes will be more than adequate for most audio -- if you already have a scope there are lots of ideas on the web --

The HP3581 Wave Analyzer is usually available for under $100 -- this device has a great RMS detector, tracking generator and will measure down to the nanovolts at a few Hertz -- one of EBay's great gifts to DIYAUDIO land. If you replace the NiCads you can take it anywhere.

Hello

That HP3581 Wave Analyzer seem a best buy, for now there is none of it in Ebay but I will look for it.

Thank

Gaetan

[jackinnj]

Originally posted by gaetan8888
That HP3581 Wave Analyzer seem a best buy, for now there is none of it in Ebay but I will look for it.

The crystal filters in the 3581 are much better than RC filters used elsewhere. You can use the 3581 as a very acurate THD analyzer as well.

I would say that this is a case where it just isn't worth it to roll your own if you can find a 3581 in decent shape. The only thing I would add is a data acquisition card so you can download the data into excel -- but this is only an expense of some tens of dollars ( multiply by 1.3 for Euros