I think Topping has really nailed the look of budget desktop products in this style, bringing some much needed elegance to the design:

Even the power/input selector feels elegant to touch with a reassuring relay click.

And yes, there is balanced input now in the form of TRS connectors which is very common in Pro space:

As noted, you can actually select between them so you have dual inputs, albeit, in different formats (balanced and unbalanced).

As you see, a rather large and high current external power supply is provided which likely sets the limit of how much it can output. Unlike other budget amps in this class, it is branded by Topping and safety certifications seem legit.

In use, the amplifier ran cool and at room temperature even after all of my tests. Its protection circuit never intruded and the amp was comfortable being pushed well into clipping with no shut down, etc.

Achieving full 16 bit dynamic range is very difficult for most amplifiers and PA3s delivers on that. Part of the reason for good performance here is that the amplifier gain is lower than what is common at 20 dB. This is actually fine though as full power can be achieved at under 2 volts with balanced input which any desktop DAC can produce. So might as well put that higher input voltage to good use and improve amplifier noise performance.

I am always nervous running frequency response tests on class D amplifiers, worried that they should have variations at high frequencies. The PA3s put my worries aside:

Conclusions
Up until now, I have not been a fan of Topping power (speaker) amplifiers. Their performance was simply not that good. With the advent of new chip-based amplifiers with better performance, Topping had fallen behind even more.

Here, it seems they have taken a standard platform and really optimize it as they do with their DACs.

This shows in very low noise level, nice crosstalk and excellent frequency response.

My only miss is the amount of power available if you were to use this for main hi-fi system.

Overall, I am happy to recommend the Topping PA3s amplifier. Welcome to the games Topping! 

https://www.audiosciencereview.com/forum/index.php?threads/topping-pa3s-review-desktop-amplifier.27079/