So how about output power? Do you use low impedance phones?
Perhaps?Topping NX4 DSD has a Line-in and functions as a pure amp too. Perhaps it should serve your need?
Roen, your calculations are based on a poorly labeled graph. I scratched my head too when I saw it. Hey, it happens. Note that it should be 4.2V @300 ohm and 2.2V at 30 ohm. Don't have calculator handy but clean power is about 59 mW. I noticed this a couple of days ago, and mentioned it to Amir.
As noted, loaner unit is here. It is just that I have a massive pile of gear to review....Sure, if we could get @amirm to review / measure an NX3, that'd be nice too.
https://www.audiosciencereview.com/...th-and-jds-o2-headphone-amps.3928/post-126360
Based on this, you still get 2.6-ish V at 300 ohm on O2 battery, so still a bit stronger.
D50 being fed off the phone is the source.A lot of guys are trying to help you out. Is this for a phone as source? Otherwise, a DAC/Amp like the NX4 would be a better proposition.
No, no. I see distortion knee at around 4.8V with O2 on the graph. Now look at NX3s: starts rising around 4.2V but still clean at 5V. Roughly comparable. I'm speaking of 300 ohm.
Nx3s graph:
https://ae01.alicdn.com/kf/HTB1ieLnXLfsK1RjSszbq6AqBXXaA.jpg
Don't know where you read 2.6 VRMS. The trace that dips the lowest is always the 300 ohm.