Audio Normalization

[weisguy]

As of this weekend I have reduced my entertainment center to ONLY my amplifier and GBPVR, since GBPVR is now performing all the duties my CD player, DVD player, VCR, and cassette deck (yes, I still had one!) used to do.

Playing all my music this way, I have quickly realized that differences in the perceived loudness of my MP3s need to be dealt with, hence this poll:

How do you normalize audio playback?

[elite]

The thing I find most annoying is how loud adverts are compared to TV shows

[ACTCMS]

I have a collection of over 14,000 MP3s ripped from CD, vinyl, audio cassette and DVD soundtracks. MP3Gain has never let me down.

[scb147]

Question about MP3Gain... it tells me a lot of my mp3s have clipping. Should I re-encode all these mp3s in order to get rid of this? Just seems like a lot of work.

[weisguy]

I have a collection of over 14,000 MP3s ripped from CD, vinyl, audio cassette and DVD soundtracks. MP3Gain has never let me down.

Dang... I have 8K and I thought my collection was large. I hope the RIAA doesn't read this board.

[ACTCMS]

Dang... I have 8K and I thought my collection was large. I hope the RIAA doesn't read this board.

I believe them all to be legit - I either bought the cassette, album, cd or inherited them from my parents and I've still got the originals up in the attic. As far as the few originals I have "lost", well it just shows the wisdom of backing them up to MP3

[Hairy]

Although I can completely understand why people prefer to "normalize" their audio. Could I just throw in a slight note of caution.

Normalization (in it's truest form - Peak Level normalization), analyzes a waveform and finds it's peak level. It then calculates the gain increase need to raise this peak level to a predetermined dB level (usually 0dB) and applies this gain increase to the entire wave. Basically turning up the volume. This then should leave the dynamic range (ratio between the loudest and quietest parts of the waveform) intact.

Now the rub. You need to analyze the entire wave to find it's peak and apply the unified gain increase. But as far as I know, if that wave is being streamed the normalization calculation is made on what the plugin can see of the wave at that point. The result usually is that the dynamic range is inevitably altered. The main reason you hear this large difference in volume today is because over the years we have become hooked on increasing the RMS average of our audio. Radio, TV and modern music has an extremely low dynamic range.

I'd argue that the best way to tackle the gain difference is to simple turn your gain level up or down, where needed. But I completely understand why thats not for everyone. So here's my 2c:

You should avoid normalizing when you rip to MP3. If you have to normalize your audio, then it's probably best to do it at the output stage, and try to be as sparing as possible.

And so ends my preachy post of the day

[tieke]

Question about MP3Gain... it tells me a lot of my mp3s have clipping. Should I re-encode all these mp3s in order to get rid of this? Just seems like a lot of work.

The good thing about MP3Gain is that it doesn't actually re-encode the files - it just alters the volume multiplier (or words to that effect), so you can easily change the level back without affecting the quality. On the other hand, I seem to remember that its default gain was a bit low for me, and if you don't have any problems with the sound of your current mp3s, you might as well leave them well enough alone

tieke

[ACTCMS]

Question about MP3Gain... it tells me a lot of my mp3s have clipping. Should I re-encode all these mp3s in order to get rid of this? Just seems like a lot of work.

I converted my vinyl and tapes by connecting my hi-fi to line-in, recording whole album/tape to wav, ripped to tracks using LPRipper, converted to MP3 using MusicMatch, tagged them with ID3Renamer and normalised using the MP3Gain defaults one album at a time. As long as the album overall showed no clipping, I just ignored the occasional track warning. I then MP3Gained all my CDs at the default level. I completed the whole excercise (about 1000 albums)over about 6 months, and I'm very pleased with the result. I mostly start off a random play on the entire collection - and I've never needed the volume control yet.