Can this mixer work with 220v power or its 110v US only?

It works with both of them. You just need to change the cable from the US plug to EU one. There "110-240 V ~ 50/60 Hz 40W" is written on the shield at the bottom side of the mixer.

What's the difference between the nexus 900 and mk2 750 in sound quality

Sound quality is outstanding difference is that mk2 750 doesnt have a link output and it has fewer effects

Whats the power input can it work 220V ac?

I have always used it with the usual electricity.

So what would be some differences between this mixer or 450, compared to a more advanced controller. i have an an sb2 with serato pro.

You are unable to connect the turntable to ddj-sb controller for instance. This also means no DVS support with sb2. These are first what I was thinking about. Hope that helps.

ASIN	B074L92B6W
Audio Input	USB
Brand	PIONEER
Brand Name	PIONEER
Connectivity Technology	USB
Connectivity technology	USB
Customer Reviews	4.5 out of 5 stars 51 Reviews
Global Trade Identification Number	00841300100751, 04573201240842
Included Components	DJ MIXER - 4 Channel (Black)
Item Type Name	PIONEER DJ
Item Weight	8.39 kg
Item weight	8.39 kg
Manufacturer	Pioneer DJ
Noise Level	105 Decibels
Number of Channels	4
Number of channels	4
Output Connector Type	USB
Output connector type	USB
Power Source	Corded Electric
Power source	Corded Electric
UPC	841300100751
Unit Count	1 Count
Warranty Description	1

DJ DJM-750MK2

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