* 【Bolanle PH400 Headphone Amps】: Amplifies sound and features four independent volume control output ports and a mute button. It provides a wide volume range, clear sound, and low distortion. * 【Mono/Stereo Mode】: Bolanle Guitar headphone amp has a mono/stereo switch that allows you to flexibly select options to meet different needs in various situations. * 【3.5mm/6.35mm Headphone Jacks】: Bolanle Headphones amplifier is equipped with 8 non-interfering headphone jacks. 4 x 3.5mm (1/8 inch) headphone jacks and 4 x 6.35mm (1/4 inch) headphone jacks. * 【7-Color Breathing Light Buttons】: When adjusting the volume, you can see 7 different colors of breathing lights, enhancing the atmosphere. * 【DC 12V 2A Secure Power Input】: The Bolanle in-ear amplifier is equipped with a reliable 12V power supply, ensuring stable and efficient power delivery while ensuring optimal safety. * 【Ultra-Compact Design】: The Bolanle Headphone guitar amp measures only 3.11*5.75*0.98 inches and is made of full metal. It saves valuable studio space. desertcart.com: Bolanle PH400 4-Channel Headphone Amp with 8 Output Ports, 3.5mm & 6.35mm Jacks, Mono/Stereo Switch, 7 Color Breathing Light : Electronics Review: I love this little amp! - I'm always needing just one more headphone amp or something like a D/A with adjustment, which this product does quite nicely. I wasn't expecting a lot, but it looked like a solid build, I liked the controls and layout, and the USB power was a plus. I thought the lighted knobs were a little over the top, but I was ok with them. Once it arrived, however, I was pleasantly surprised as to the quality of the unit. Solid, well laid out, and the audio quality was much better than I expected. The outputs actually push quite a bit of gain, something I sampled with my IEM's to test quality and how much power the outputs would push. I don't have a good set of ear cans to test with at the moment, but given how little gain I had to push compared to some of my other headphone amps, this unit would drive a set of over-the-ear headphones just fine... Probably with headroom to spare. In addition, the output was way cleaner than I expected out of a unit at this price point. The reference material I use to test new headphones and other gear sounded great, with no noticeable deficiencies and a lower-than-expected noise floor. I'll also admit to the fact that I actually really enjoy the 'Breathe' lighting, as cheesy as I thought it might be. They also make an 8-channel version of this unit, and I think I might just end up owning that one, too. Very pleasantly surprised!!! Review: Have some old computer speakers laying around? Hook several up with this unit! - I looked at quite a few headphone amps and picked this one for several reasons. 1. It has mute buttons for each channel. AND the buttons are below the knobs vs above the knobs. Why would you want to have to reach over the knobs to mute? 2. The knobs and mute buttons are pretty centered to the unit. There are many where it's closer to the far end vs closer to you when laying flat. 3. The colored LEDs are a cool touch. 4. Has both 3.5mm and 1/4" outputs. I put mine on a gooseneck with a tablet holder to keep it off the desk with 90 degree cable ends for a cleaner look.