![Mackie HM-4 Headphone Amplifier Mackie HM-4 Headphone Amplifier](https://cdn11.bigcommerce.com/s-sjkuycrcgv/images/stencil/300x300/products/7326/14340/2049177-00_HM-4_Web__97911.1696534404.png?c=2)
The 19" Rackmount hm-400 4-channel headphone amplifier offers an incredible amount of versatility and excellent sound quality in a single rack space. Perfect for professional applications including studios, houses of worship, practice spaces, and more. The hm-400 features a main input with level control plus stereo outs, aux inputs and EQ per channel with 12 total headphone outputs.