Chris's Compressor effect on CD burns???

[ignatz]

Steve:

Thanks for the continued help.

I just burned a bunch of songs with Chris at default setting except I chose .98 amplitude on the output rather than .99.

I am generally happy with the results except for one song. It still plays noticeably louder than the other 32. The other 32 do not differ noticeably in volume. Before this default compression test, there were 4 or 5 that had slight noticeable differences--so the compressor is having some desirable effects.

After compression and before compression waves for that still problematic song are shown here.

Do you see anything in the before waveform that would lead you to believe it might still be louder than the others after compression---i.e., not react as the other songs did to compression and amplitude choices in Chris? The song is question is a circa 1960 country recording.

Entirely possible my technique is bad---given that my goal is equal volume across 33 tracks, should I be running all 33 through a compressor---or only certain songs (the quiet ones, the loud ones, whatever)???

If that is true, it may be less labor-intensive to not use a compressor at all and go back to the old manual "test burn and then adjust a few songs for a reburn".

The remedy for that one song might be to compress it more or less than the others, but then I am back to trial and error and fiddling--which I had hoped to avoid.

Any comments appreciated.

[steve]

Do you see anything in the before waveform that would lead you to believe it might still be louder than the others after compression

The levels in that song are fairly constant throughout (very little dynamic range), so all that has happened by running it through the compressor is that the volume level of the entire song has been raised a bit.
The waveform also looks quite "dense", so it is likely to sound louder than songs that have an equal peak amplitude but more variation (more of the audio at a quieter level and less peaking up to the average level of this track.

it may be less labor-intensive to not use a compressor at all and go back to the old manual "test burn and then adjust a few songs for a reburn".

What I do is that I've got a Behringer UCA-202 USB sound card (about $25) that I can plug into my computer, then connect to my music system. This means that I can listen to the tracks through my music system before I burn them to CD. I would normally listen to the tracks while they are on the computer (through my music system) and adjust the levels using the volume slider in Audacity so that it roughly matched my "reference" level.

I would only tend to use compression on tracks that were generally low volume but could not be amplified up to the same "loudness" as the other tracks due to having a few exceptionally high peaks (which would distorted if I tried to increase the level further). What the compression effect does with that type of track is to raise up the level of the quieter parts without increasing or distorting the loud peaks. Thus the track overall sounds louder and matches the other tracks better.

[ignatz]

What I do is that I've got a Behringer UCA-202 USB sound card (about $25) that I can plug into my computer, then connect to my music system. This means that I can listen to the tracks through my music system before I burn them to CD. I would normally listen to the tracks while they are on the computer (through my music system) and adjust the levels using the volume slider in Audacity so that it roughly matched my "reference" level.

I would only tend to use compression on tracks that were generally low volume but could not be amplified up to the same "loudness" as the other tracks due to having a few exceptionally high peaks (which would distorted if I tried to increase the level further). What the compression effect does with that type of track is to raise up the level of the quieter parts without increasing or distorting the loud peaks. Thus the track overall sounds louder and matches the other tracks better.

Gotcha.

I've got a Behringer myself--the variant with the turntable input.

I think pre-listening through a sound system is probably the better alternative, considering virtually every CD I burn has a song or two that needs adjustment. Better to fully evaluate before the burn rather than after.

I just don't tend to notice minor volume variations in shuffle play among thousands of songs on a hard drive like I do on playback of a 25 or 30 songs from a CD. That might be because I often use HD play as background noise, but listen more attentively when I choose a CD.

Nor do I recall going through this unequal volume business 20 or 30 years ago when I was constantly making cassette anthologies from vinyl and a turntable. But of course in that case, I was feverishly attentive to VU meters and today I am largely taking mp3s as I find them.

Thanks again--I do appreciate the insights.