Some people like to hear music precisely as it was recorded, which is why the most expensive audio equipment purports to do absolutely nothing to affect the original audio signal.
Others like to tweak their sound, often in the bass range. Reducing bass frequencies stops music from bleeding through walls and waking up babies, which is a good trick to know, if you should ever need it. As for increasing the bass volume, well, that gets the party started — or at least make you feel like you’re wearing headphones by Beats (they’re notoriously bass-heavy).
Whether you’re on a Mac or PC, there’s a way to set a global equalizer across everything — iTunes, browsers, Spotify, Rdio, Pandora, iHeartRadio, or whatever else you listen to. Even your system sounds will be affected. If you’re a sound-tweaker, this is important information, because it means you no longer have to hunt around for the equalizer that is missing from most of those apps anyway. The instructions vary based on whether you are on a Mac or a PC. Let’s start with the Mac.
On a Macintosh
The keys to this bit of musical magic are entirely free software: Soundflower, from Cycling74, makers of the (amazing) Max/MSP software, which lets smart people build neat stuff (including an NES danceclub visualizer, a heartbeat-driven “Call Me Maybe” controller, a city-remixing taxicab, and invisible dubstep instruments); and AU Lab, from Apple itself.
Here’s how to use Soundflower and AU Lab to control sound equalization globally, so that you can affect all of the sound your Mac makes with the same EQ setting:
1. Install Soundflower
This part is easy – as is the rest of this tutorial, for that matter, although some of it looks a little tough. Just grab the most recent .dmg file for your system, and click it after it downloads to install it, just as you would any other Mac software from the web.
2. Install AU Lab
3. Restart Your Mac
You know the drill.
4. Turn Your Volume All The Way Up
Before you monkey around with the rest of this stuff, turn up the volume all the way on your Mac with headphones plugged in, then do it again without headphones plugged in. Once you complete this process, volume will get controlled at the next part in the chain, so if you start out too quiet, you won’t be able to get back to top volume.
5. Make Your Mac Output to Soundflower
The beauty of Soundflower is that your Mac thinks it is an audio output, which, in a sense, it is. To set up your Mac to route all sounds to Soundflower, go to System Preferences > Sound, and choose the two-channel Soundflower option:
6. Make AU Lab Input from Soundflower
Go to Applications > Utilities, and double-click AU Lab to open the program. Now, you just need to set the input to Soundflower, like so, and then click Create Document:
Now you can see under the hood of AU Lab, which can add a wide array of effects to your sound. Unless you want to experiment with the rest of them, proceed directly to AUGraphicEQ, and select it as an Effect in Audio 1, on the left:
8. Tweak It
AU Lab defaults to giving you 31 bands of equalization, which allows for fine tuning — probably too fine, for most purposes:
You’ll probably want to switch to the 10-Band equalizer instead using that dropdown button to the lower left. Here’s what that looks like with the bass frequency sliders dragged up for more low-end:
You can save it as a preset like this:
Now, every sound your Mac makes will be EQ-ed just how you like it. And if you followed Step 4, you’ll still be able to use your volume keys to reach your Mac’s top and bottom volume levels. (If you skipped that, you can go back and change it after the fact.)
On a Windows PC
Windows has a native equalizer. It behaves differently under different configurations, but this is the basic idea. Also, depending on your soundcard, you might see another option in Control Panel for changing the equalization on that soundcard. We recommend playing around with that too, if you see it, because it could offer more control than the generic Windows presets do.
1. Open Sound Controls
Go to Start > Control Panel > Sounds. That looks like this on Windows 7:
You have some music playing, right? No? Well if not, start some, using whatever application you want. Once it’s playing, you’ll see little green bars light up next to the thing that is playing your music. Double-click that.
Now you’re in the control panel for output you use for music. Click the Enhancements tab to bring up a bunch of options:
With some soundcards, you can access a graphic equalizer like the ones your Mac friends can use in the above instructions. On my fairly standard HP box, you can only choose presets. To find out how they sound right as you select them, check “Immediate mode,” and then start trying the presets:
If I were you, I’d try that “<Custom>” setting too; on my box, nothing happens, but I have seen evidence that it works on other Windows machines. Either way, you have now set an EQ setting globally, across your entire PC, once you hit the OK button.