There are various audio equalizer add-ons available that can enhance your audio experience. These add-ons can be used with different devices such as headphones, speakers, or even your smartphone. Some popular audio add-ons include equalizers, amplifiers, and soundbars. Equalizers allow you to adjust the sound frequencies to your liking, while amplifiers can boost the volume of your audio. Soundbars are a great option for those who want to improve the sound quality of their TV or home theatre system. Overall, audio add-ons can greatly enhance your audio experience and provide you with a more immersive and enjoyable sound.