The korsun / dussun v6i is a monster of a power amp from china costing around 800 usd. It really is a poor man's krell or Mark Levinson that is built like a tank with dual mono construction in 1 stunning but large aluminium chassis. It is kind of a class A build in that the first few watts are class A were then it slides into class AB mode as it is driven harder; with output powers of 2x300 W into 4Ω and 2x150 W into 8Ω.
Sonically the dussun V6i was rather hit and miss. In the right combination of source and speakers it could sound good but more often than not it sounded a bit lack luster. The main issue I found with this amp was the lack of dynamics and musicality. No matter how loud it was driven into certain speakers it sounded a little flat and soul less. It was too source and particularly speaker dependant.
This amp can be split by links at the rear so it can be used as a pure power amp. I ran the amp in power-amp only mode using a DIY 12b4A tube pre-amp and this was a much better combination on Monitor Audio Studio 20SE speakers, the tube pre adding vastly better dynamics than the built in pre and a little warmth to the cold sound. This seemed to be the preferred way to use this amp but it kind of defeats the purpose of buying an integrated.
On a pair of Martin Logan electrostatic speakers the V6i in power amp mode was again not a good match as I had hoped for when compared to driving the Monitor Audio Studio 20SE. The amp again sounded a little flat and un-dynamic most days. It hardly got warm to touch no matter the load or levels so it made me believe it was very under-biased, under driven and capable of much more. I think this could be a good amp in the right system and just a shame I did not have a service manual to tweak or modify it. I am sure Duusun could make some minor changes to the design to improve dynamics and maybe add a little warmth and soul to the sound. As it stands I would only recommend this amp if you can pick it up for a very low price and are a regular box swapper meaning you can find a good combination of speaker and source to match it and bring out its best,