Equalify

Equalify is an audio equalizer plugin for Spotify that lets you tweak how your music sounds.

• Visualizer - built-in audio spectrum analyzer that gives you the ability to be entertained by dancing colors or adds a little pizzaz to your filters.
• Device changer - change output devices with ease, no need to restart Spotify.
• Parametric-Ability to add as many bands as you want to any location. You can select between a low/high pass, Peak, low/high shelf, and notch filters for each band.

Since the creation of the original Equalify plugin, there have been many changes is features and visuals. 

Equalify is now fully parametric and can change the output device while music is playing without pausing it or having to restart Spotify. The multitude of settings makes it easy for you to get Spotify working and sound like you want it to. There is also a limiter in Equalify that will let you tweak your bands to your heart's content without worrying about clipping the signal. You can save as many presets as you like, and it's easy to switch between your saved presets.

Can change output devices with no interruption to Spotify

It is easy to install. You log in to create an account, choose whatever license and models fit your needs, pay for your purchase, and then the download begins. When you launch Spotify the first time, you may be asked for your Eqaulify username and password, enter the information, and Equalify will be activated. You will see the green "equalizer" next to the Spotify icon. You can click on this, and it will open Equalify, and you will be on your way to adjusting the way your music sounds.