Which DACs bypass digital filtering?

2 hours ago, woshifeng3627 said:

It seems that AKM 4499EX can only perfectly play DSD128-256 in DSD direct mode

Yes, this is what I've been saying, because it natively only supports these two rates, nothing else. DSD64 although works as well, but it is not recommended and kind of "underclocking" thing. I would say DSD64 should be always played through some upsampling, just like 44.1/48k PCM.