Audio Recording

If you have Audacity installed either in Windows or Linux; you can use it to analyze the frequency spectrum of your recorded audio signals.

Performing frequency analysis can reveal some of the mixing and mastering process problems in working with an audio project. For example, using frequency analyzer in Audacity lets you know:

a.) The volume level of a certain frequency range. This means that you will know whether your bass/sub-woofer bass is too low as compared to a professionally mixed/mastered track provided both compared tracks are at the same volume level (average dB SPL).

b.) Since the graph/plot is frequency vs. amplitude (as opposed to normal waveform you can see in all digital workstations that show the plot as amplitude vs time). This is a very important tool that you can use to diagnose either amplitude related problems in frequency ranges or vice versa (frequency related problems in certain volume level.)

For best results:
a.) Use a high resolution WAV file (24 bit at least).
b.) Audacity lets you analyze the whole waveform but it is limited to only 237.8 seconds of the entire wave. But this is enough to let you judge the entire waveform.
c.) You can also select a certain problematic area in the waveform and then use frequency analysis to make a plot of that selected area. This is particularly useful if you are analyzing noise related problems in a waveform (such as spike).

To get started:
a.) Launch Audacity.
b.) Open a high resolution WAV file.
c.) Once the file has been completely loaded in Audacity. Select a certain region of the waveform you need to analyze. If you need to analyze the entire waveform, just go to Edit – Select – All.
d.) Go to Analyze – Plot Spectrum. For more accuracy, you can increase the size from 512 to a much higher value. You can even export the report if you like to do more analysis outside Audacity.

You will then see a result like below:

You will notice that frequencies above 20Khz are cutoff. And then there is a slight boost of high frequencies at around 15Khz.

It also shows that it has a pretty solid bass/sub-woofer.

How to implement frequency analysis in mastering and mixing projects?

Note to beginners: While frequency analysis offers a graphical tool to let you know problematic frequencies, it is highly important that you will NOT rely on this tool alone in your mixing and mastering projects.

For best results, this frequency analysis tool will be used along with your ears. For example, if your ear spot a certain problematic frequency range, then you can use frequency analysis tool to confirm your observations.