How to RTA a digital source directly?

[BenToronto]

I recently posted this in another AV sub-forum and I can't figure out how to remove it from there. So, I hope this repeat doesn't violate the rules.

If REW was a box like a voltmeter and if I wanted to RTA the content of an organ recording, I'd know just how to connect the cables.

But my recordings are digital and they are in the same computer as REW. How to get REW to RTA that digital source?

I'm using a MacBook Air laptop. What I do at present is output the music from one port and input it to REW at another port (say, USB out to a DAC and then input via external mic (AKA headphone jack)). While it works quite well, that method seems needlessly complex and prone to noises.

Thanks.
Ben

 

[John Mulcahy]

If you extract portions of the recordings you want to analyse as WAV files you can load them into REW directly using File -> Import -> Import audio data. Should keep the sections reasonably short, REW will only import the first 60s or so of a file. Audacity is good for selecting sections of files if required, and you can also view the spectrum directly in Audacity.

 

[BenToronto]

If you extract portions of the recordings you want to analyse as WAV files you can load them into REW directly using File -> Import -> Import audio data..

Many thanks for your help.

60 seconds (and some guessing what part to cut for analysis and fussing to select it in Audacity) can be helpful. Does that work with Apple Lossless and other format? Or selections that run longer but the files are compressed smaller size?

But watching an organ recording (or any other source) with low pedal notes "play" on your RTA is thrilling and at the end, you see the frequency peaks for the whole piece.

Still, it would be a wonderful addition to REW to be able to simply choose as an input a music file that is playing and to do so without having to output the music with one jack, into a DAC, and input it with another, as we have to do now.

Ben

 

[AudiocRaver]

VB Audio makes some donationware utilities that include stereo Virtual Audio Cables for connecting an application output to an application input. They work well but can be frustrating to get set up and working right (reboots, stop/start/stop/start, change to another input then back to the one you really want, then again, then again, there it works!, etc.)

Once it is working, it is quite reliable. Getting it going might test your patience.

 

[BenToronto]

Thanks for suggesting the app. But isn't it only Windows?

I wonder how hard it would be to incorporate that functionality into REW? Seems to me that being able to connect REW to related programs would be useful to many, not just with mics as an the input.

And further in that vein, I otten wish REW was more of an oscilloscope and similar virtual hardware. For example, checking speaker impedance. Currently, a stretch to get loud signals into a computer even when they can arrive in audio coax format.

B.

 

[AudiocRaver]

You are right, I missed the MacBook Air mention in your first post.