Author Topic: What is normalization? (Read 14625 times)

Harbinger · « **on:** July 04, 2009, 22:55:34 »

Did a search in the forums, but can't seem to find an answer. And i need it for the manual....

What exactly is normalization of a sample? What technically is happening, and what is the audial effect?

Sam_Zen · « **Reply #1 on:** July 04, 2009, 23:21:07 »

Not much of an audial effect, except overall volume.

The normalization formula scans the total sample looking for the highest peak qua amplitude.
Then maths are simple : with how many dB could this peak be amplified before passing the clipping barrier, the 0 dB point?
The same amount of amplification then is applied to the whole sample.

I prefer more sophisticated apps having manual setting for a custom percentage, like 96 %, just to prevent edgy problems.
Normalization seems a good tool to make samples basically stronger in main volume.

Of course a sample should be as loud as possible. It's easy to code it with a less volume, having a more precise range,
while having a weak sample, if one needs to amplify the source in the 'plus', noise artifacts will be amplified as well.

Harbinger · « **Reply #2 on:** July 04, 2009, 23:32:48 »

Layman's terms, Sam! You explained it perfectly i'm sure and i still don't get it.

Assume i'm new to using samples. When would i need to normalize? What will i get when i use it? Should all samples be normalized? Why or why not?

I can still use the technical info, but i need info on its practicality and its benefits/disadvantages.

Saga Musix · « **Reply #3 on:** July 05, 2009, 00:05:00 »

Basically, it makes the sample as loud as possible by multiplying all values with a constant which is chosen by taking the maximum amplitude of the sample. Benefits? A sample that has 50% "volume" doesn't have to be played unisono on two channels just to be loud enough to be heared! It's always good to use normalized samples, especially when you plan to convert them to mono or 8-bit, because less information will be lost then.

Harbinger · « **Reply #4 on:** July 05, 2009, 00:39:08 »

I still only partially understand, but enough to help new users to sample editing with MPT. Thanks, sam and jojo!

psishock · « **Reply #5 on:** July 05, 2009, 03:30:29 »

It would be easier if you pick up the parts that are not clear. Sam answered really good, we use normalisation to make everything sounds as loud as possible. It has more than one benefit, but it depends of course from many views, how much these benefits are important to us. For instance, if you want to listen to a playlist of a songs, you don't need to mess with the volume bar on each of them, just set it once for optimal, every other song will sound with "right" volume. If you normalise a fairly low volume sample, messing with it after will cause more precise sounding. Lowering a volume by any percent is not a problem at any time, but if you need more stronger volume than your current sample totally has, it's usually a trouble (Jojo stated this problem 2). I could think of some more examples if needed, so what are the questions about the topic, that are still not totally clear.

LPChip · « **Reply #6 on:** July 05, 2009, 09:07:41 »

If you want a different explaination, the take this one:

Normalising basically stretches the volume vertically in the samplewindow to fit the entire window. If the sample is already stretched throughout the vertical axis, normalising will not do anything to the sample.

This stretching will usually make the sample louder.

Basically you always would want to normalise, to get the max out of your sample. You can always use the volume settings to make it softer again (both from the sampletab and patterneditor)

Basically, the higher the volume of the sample, the easier you can work with it, but if you would amplify it over the clippingrange (thus it would be stretched outside the view) it will start to cut from your sample where it stretches out resulting in a worse quality (though sometimes people want the side-effects).

Do note: once you amplify your sample outside the patternview, and you then unamplify the sample, you will see that it has cutoff the part that was outside, and instead drawn a straight horizontal line in that cut. This will ensure that the same volume is being reached as was before, but due to the change in waveform, the sound will be sharper, and usually that sharpness is unwanted.

Sam_Zen · « **Reply #7 on:** July 05, 2009, 17:39:11 »

As LP says, it's a possible expansion vertically, so volume.

The sample of A clearly needs some normalization, one can see the room.
The sample of B can't have any normalization, because the loudest peaks already are at almost 100 %.

btw : you can find some additonal info and tips at my Sample pages

PPH · « **Reply #8 on:** July 06, 2009, 16:26:51 »

Very simplified layman explanation: normalizing a sample is making it as loud as possible without distorting it with crackles.

machinesmith · « **Reply #9 on:** July 08, 2009, 13:19:06 »

*tears himself away from laborious tune manufacturing*
...and to add part 2 to PPH's excellent explanation:

In tracking Normalization is usually applied to All samples in a song so that they sound the same (ie "heya, no unecessary fiddling with that volume column except for fade ins/outs! Nice!" (amongst other things))

(the latter part of Jojo's post pretty much covers the `why' ... LP's comment adds to the `what else can I achieve from it' aspect - works really well with crunchy rock guitars, I know your secret Ramms+ien!)

*runs back to computer!*

Louigi Verona · « **Reply #10 on:** July 08, 2009, 13:26:11 »

I did however notice that normalized file sounds a bit... mmm... different. I try to not normalize sounds.

psishock · « **Reply #11 on:** July 08, 2009, 15:08:58 »

that asks for further explanation LV, the procedure does not distorts the sounds in any form, just amplifies it, so i assume that your "different" is a bit....mmm.... louder?

Saga Musix · « **Reply #12 on:** July 08, 2009, 19:28:13 »

Quote from: "Louigi Verona"

I did however notice that normalized file sounds a bit... mmm... different. I try to not normalize sounds.

it should sound the same if you turn up the volume of your system or your amp. sure, the "fidelity" is different, but that's not due to the algorithm used. it's just because everything is louder. music sounds different when you listen to it at a higher level. that's completely normal.

BTW: Awesome new avatar, psishock.

Louigi Verona · « **Reply #13 on:** July 08, 2009, 20:30:34 »

I always thought normalization and maximization are different things. Afaik, normalization is when the volume is evened out. Maximization is when it is maximized - all of what you guys said in this thread. I might be wrong, but GoldWave certainly made such a difference in older versions.

Saga Musix · « **Reply #14 on:** July 08, 2009, 20:40:06 »

normalizitaion in goldwave terms would be compression or limiting then. Normalizing in modplug (and other audio apps) doesn't do such a thing, it simply amplifies the whole sample as much as possible. period.