Editing FLAC, and Normalization

Have a couple questions:

  • If I am importing FLAC to edit, should I decompress the file before performing any operations on it or does Audacity do that automatically?

  • I have some files that were digitizations from vinyl. Most if not all have a channel imbalance of 3-4 dB. I have done Normalize> Peak value>Treat each channel Independently, thinking that should do it, but the imbalance persists. What next? (FWIW my old copy of Amadeus does’t fix it either.) I guess I’m missing something but not sure what. Screenshots attached. A left& right waveform, and meters. Suggestions for next steps?

Thanks in advance

Oh, I forgot… As requested: Mojave 10.14.6, Audacity 2.3.3. I guess I will have editing options after a certain point. Thanks again.

Audacity will decompress when you open the file.

. I have done Normalize> Peak value>Treat each channel Independently, thinking that should do it, but the imbalance persists. What next?

The peaks don’t necessarily correlate with loudness. Matching the RMS levels should work better (and if that doesn’t work you can do it by ear).

Download and install the [u]ACX Check plug-in[/u]. It will appear under the analyze menu, and it will give you the RMS levels for left & right as well as some other “numbers”. (You can ignore the pass/fail information, that’s for audiobooks.)

After running Normalize independently,
Run ACX check and subtract the RMS levels to find the dB difference.
Click the drop-down arrow to the left of the waveform and select Split Stereo Track. (That allows you to adjust left & right separately).
Select the “louder” channel and then Amplify by the dB difference (entering an negative number so you are attenuating instead of amplifying).

Okely dokely… Hoping DVDDoug sees this.
Been busy as he|| and haven’t had any time but now am revisiting this.
Downloaded the plug-in, ran the installer, got successful install message.

Can’t find it any of the menus (including ‘Effects’ and ‘Analyze’) or figure out how to make it run. I’m sure I’m making some kind of rookie mistake…
Ran the 2.4 update today, in case that is relevant.

After installing a plug-in, it needs to be enabled in the Plug-in Manager.

The “ACX Check” plug-in is a Nyquist plug-in. Instructions for installing Nyquist plug-ins on Windows are here: https://manual.audacityteam.org/man/installing_effect_generator_and_analyzer_plug_ins_on_windows.html#nyquist_install

Thanks Doug & Steve.
This plugin pretty much ended any need to keep my ancient Amadeus app as it replaces the ‘Waveform Statistics’ report function.
Once I enabled the plugin properly, it gave me the following report on the first track I analyzed
Screen Shot 2020-05-19 at 10.25.06 AM.png

I was a litlle surprised to see that the difference looks lowe than you’d think as the meters pretty much track each other as shown in my OP.
Just (hopefully) two last question: In the Effects menu, there are (apparently new to 2.4) new options under Normalize.

In addition to RMS as recommended by Doug above, there is a new Normalization option: Perceived Loudness.

1)How do they differ and which would you recommend?
2) Is it a ‘best practice’ to use the ACX standard levels (peaks no higher than -3dB)?

Many thanks for all the help. I’m going to donate to the Project. Unless someone requires something on the level of Logic Pro, I think Audacity is all most people need.