Jude over at Head-Fi has a video review of the recently available Woo Audio portable true tube amp and DAC combo WA8. It is has three tubes and runs in either a 2 or 3 tube configuration. Power is supplied via battery regardless if using on the run or when recharging at home. The battery last around 4 hours and of course indefinitely when charging at home.
Jude tried the WA8 with various top shelf headphones and loved it. He also tried it with a custom IEM and was amazed at the sound floor of the WA8.
Go over to Head-Fi by clicking the link below and listen to Jude’s review. BTW, the WA8 will set you back upwards of $1,800 for the gold version.