Why would you want to listen to LO with Z1R ? That is for external amplifier.
When speaking of LO into external amplifier. The Ibasso DX300Max Titanium is special enough to invokes me to build a high end headphones amplifier for it, just to maximize the benefit of having the DAP, either on the go or sitting on my bed.
After I built my amplifier, I got a confirmation that the 3MTi is a monster of a value and something to be hold for many years to come. I am glad I bought the DAP and built the amp
The amp was built with many upgrades and modifications, including Western Electric 300B tubes