Apogee Introduces Groove – Portable USB DAC and headphone amp for Mac and PC
Portable Headphone Amplifier 24bit/192khz Audio Powered Usb Dac Headphone Amp For Phone Android Usb-c Port - Headphone Amplifier - AliExpress
Amazon.co.jp: Helm Audio Volt DAC/AMP, USB-C Portable High Performance DAC/Headphone Amplifier Support MQA Playback Mobile Studio Sound USB-C to 3.5mm Audio Cable for Android, IOS and PC, THX Certified, Black : Electronics
Topping G5 is a great DAC/AMP, but... it's not that loud* : r/headphones
Amazon.com: FiiO K3 Type-C USB DAC Headphone Amp : Electronics
LH Labs Geek Out V2 USB headphone DAC/amplifier - Hi-Fi+
Amazon.com: Geekria SJC01 Portable Headphone Amplifier/DAC/AMP with USB and Type-C Input, 3.5mm Audio Jack Output, Compatible with 384K/32Bit Hi-Res APPL Music Lossless Audio, PC, Laptop, Android Phones : Electronics