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Essentially, the Ambience effect in Garageband creates a three-dimensional sound on the track through the use of a very short reverb. It also makes the sound appear thicker, wider, and more atmospheric.
This is in contrast to a reverb, which, at its maximum setting, sounds very long, as if the sound is coming from a very large and very long room.
If you increase the reverb to its maximum setting, you’ll notice that it sounds like the music is being played in a very large room.
But if you turn that all the way down, and instead, turn up the ambiance control, it sounds like a different type of reverb: a shorter reverb, that creates somewhat of a three-dimensional sound, effectively thickening up the sound and making it sound more “ambient.”
In other words, the ambience control is for any sound where you want it to continue sounding dry, but just a little bit of a 3D quality to it, with a thicker and slightly more ambiguous sound.
How Is Reverb Different From Ambience?
As I briefly mentioned above, reverb simulates the natural sound reflections that would come with a particular type of room.
Explained in another way, if you can imagine yourself hitting a snare drum in a church, the reverb is the way the soundwaves from the snare drum travel throughout the church, bouncing and crashing off the pews, the walls, and the glass windows.
For instance, if you take a look at all of the available pre-sets and settings of a reverb plug-in, you’ll notice they typically come with different kinds of rooms, like a church, a big room, a hallway, or a nightclub.
A reverb, in contrast to the ambience, will have a long reverberating sound, rather than a short one. Moreover, most reverbs that have a variety of controls provide a parameter that determines how much the sound “decays.”
In other words, when the source of the sound stops making that very same sound, there is a certain amount of time that it takes for the sound to stop reverberating throughout the room.
The decay, essentially, is the time that it takes for the sound to finally stop making noise. Go ahead and experiment with the reverb and ambience controls in Garageband and see what you come up with. Typically, I add ambience and reverb to many different types of tracks, including guitars, vocals, snare, and more.
Using Ambience on Vocals
In the case of adding ambience on vocals (I couldn’t recommend Singorama enough if you’re learning to sing), I might add just a little bit on to them, just to create somewhat of an atmospheric sound, for instance, I’ll set it to around 4-5 on the knob.
You can see what that looks like in the image below:
It’s important not to over-do it when it comes to saturation plug-ins because they tend to have a multiplicative effect.
Using Ambience on Guitars
Recently, I created a song using two different nylon string guitars, with one panned to the left, and one panned to the right. Both guitars have the ambience setting adjusted to around 3 on the knob.
You can check it out in the image below:
Using Reverb, Delay, and Ambience
In my article on how to make Garageband instruments sound more professional, I explored how the use of these three plug-ins can actually improve the quality of your music by a significant margin, and I stand behind that point of view.
How you want to set up these plug-ins depends on your own style and taste, so it’s up to you to experiment with each one individually.
Delay is different from the reverb and ambiance controls because it actually controls the echo of the sound, rather than just the way the sound waves are crashing around in a specific type of room, like the way the reverb does.
When used as a trio, a lot can be done to an instrument to make it sound a lot more interesting and fun, however, all of this pales in comparison to just buying better instruments.
Other Uses of the Ambience Setting
Bass Guitar
The ambient setting can also be used for the bass guitar, but more as a thickening agent, rather than as an effect.
For instance, if you find that the bass tone is a bit dry, you could increase the ambient setting by just 2-3 notches on the knob, and see what that does for the tone.
Similar to the use of the chorus effect, it can thicken up the sound just a little bit and bring it forward in the mix.
Ambience Makes It Sound More ‘Stereo’
I also find that the ambient function has the effect of spreading out the soundwaves a little more across the stereo image.
In other words, if you have a bass-line panned to the center without any ambience on the track, the sound has the appearence of being right in the center of the speakers/headphones.
But if you crank the ambience, it has the effect of spreading the sound waves across both headphones in a more even way, rather than just having it right in the center.
If you want to see what I’m talking about, open up a new project file in Garageband, and use the stock instrument that comes up: the classic electric piano.
In the Smart Controls at the very bottom, crank the ambience with your headphones on (here are the awesome earbuds from Amazon that I use) and play a few notes.
Now, go ahead and turn the ambience setting all the way down and play a few notes. You’ll notice what I mentioned above.
Another small addition it makes to the sound is a very, very, short echo that lasts literally a millisecond.
If you’re confused about the terms “stereo” and “mono,” understand that “mono” just means the music sounds like it’s coming through just one channel, in fact, I have a guide showing how to set your tracks up in mono.
“Stereo,” on the other hand, sounds like it’s coming through two different channels, often described as “left and right.”
YouTube Video
Conclusion
All-in-all, I would argue that the ambience setting functions essentially like a very short reverb, creating somewhat of an ambiguous three-dimensional effect that’s more defined, thicker, and more atmospheric, in contrast to the reverb, which controls the type of room in which the sounds reverberate.
I hope this answered your question.
When it comes to audio, it’s somewhat challenging to explain what a particular effect actually does due to the fact how one interprets the sound is entirely subjective.