Several people whose ears I trust have heard the AN 3.1 and 4.1 balanced. The feeling is that past 3.1 you start on the path of diminishing returns in terms of monetary value. Is the 4.1 sig better than the 4.1? Yes. Is it worth the extra money? IMHO, only each individual can make that assessment. The improvement in sound from the 3.1 to the 4.1 will be greater than 4.1 to 4.1 sig. for alot more money. I like the 4.1 bal alot but don't feel the added expense of the sig would be worth it for me(cost is an issue tho not a big one). BTW, I haven't heard the 4.1 bal sig so I haven't been able to compare the two. I thought I would share with you the thought process I went thru regarding the 4.1 and 4.1 sig DACs. Enjoy listening.