Audiophilepure

https://www.audiophilia.com/reviews/2023/2/17/hifiman-ef400-desktop-dacamplifier

With the EF400, HiFiMAN has created an impressive-sounding, contemporary-looking and powerful desktop DAC/Headphone amp at only $599. With an emphasis on simplicity of features/use on the one hand, coupled with its ability to easily engage with the complex world of streaming on the other hand, I think HiIFiMAN has a winner on their hands. And they also have headphones to match. Highly recommended.

You access the device menu by pressing and holding the volume wheel for 4-5 seconds. To switch between titles, simply rotate the volume wheel and press down to confirm your selection. The menu is rich. You can change the screen timeout time, adjust the screen brightness, turn the LED off and on, change the volume steps between 0.5db and 1db, adjust the auto gain speed, switch between UAC1-2, turn on SPDIF de-emphasis, change the DAC filter, play with the DPLL setting, see the firmware version or do a factory reset.

In addition, if you want to change the knob button behavior, you can do that from this menu. Available options are as follows; toggle output, toggle input, mute USB, and mute RCA. The navigation and controls of the device are quite simple, and menus, categories are easily comprehensible. It, therefore, doesn’t take too long to learn how to use the device. The resolution of the OLED screen is adequate and can be read without effort. Also, I really like the tactile feedback of all the buttons on the Element III. Feels great to the touch!

The LSA HyperDrive 2 Headphone Amplifier was a treat to listen to. The excellent engineering, solid construction, and very smooth sound add up to a very dynamic listening experience. On classical, vocal, acoustic, or rock and roll the HyperDrive 2 properly drove a wide variety of headphones and rendered music realistically and when needed, forcefully. Whether the source was digital, or pure analog, there was a lot to like.