Flagship headphone amplifier from leading audio equipment manufacturer Topping. The A90D is an extremely powerful, highly technical, and still remarkably musical headphone amplifier! Capable of ultra high power delivery to low or high impedance headphones with one of the lowest levels of distortion available on the market today, this headphone amplifier is truly a reference quality product that is actually enjoyable to use. This A90D is in excellent condition. It includes all of its packaged accessories - 3.5 mm to 6.35 mm headphone adapter, remote control, power cord, instructions. It has been updated to the latest firmware as of Feb 2024. I am the first owner. I loved my first one so much that I bought a second for another room, but it turns out that Im not using it as much as I thought, and I hate to see it sitting there, not getting the usage it deserves. I will be keeping my first one for quite some time to come. If you are looking for a matching DAC, please see my listing for a Topping E70 Velvet, which pairs extremely well with this amp. Same story with that one, bought a second one for a second room, but turns out Im really only utilizing one of them. Please feel free to message with any questions and happy listening!