Why I'm not adding a sub to my 2-way monitors for music

Like you have mentioned, the DSP method is another way to integrate a sub. However, the more affordable digital signal processor like MiniDSP does not have digitial OUT that allows users to connect it with the DAC

miniDSP has a number of DSP's with pure digital I/O, among them:

https://www.minidsp.com/products/minidsp-in-a-box/minidsp-4x10-hd

https://www.minidsp.com/products/dirac-series/ddrc-88d

Sadly the cheaper nano is now gone.

He knows full well the key to good bass is multiple bass sources, not a single sub

@millercarbon I would appreciate you not speaking for me, thank you.

Yes, from the literature DBA sounds like a fine idea. It is the number of devices and the religious zealotry which you have used to promote it, and this line is a perfect example. There are a number of solutions and DBA may be fine, but so is a good sub in a good room with proper integration can sound glorious.

DBA is by no means an exclusive solution but attempting to sell it as the one and only solution is akin to cultish methinks.

Uh, @audioguy85, a statement like this indicates someone who’s never experienced a sub properly set up and hence is focusing on the wrong things.  You have no idea what you’re talking about.  Wilson Audio uses subs with their Alexandrias, which go gobs lower than your speakers could ever hope to.  What do you think you know that they don’t?  Ugh. 

Yay! A new contender for most annoying poster!

Aw, c'mon Erik! You've been schooled by He Who Knows. LOL

Personally, I feel DSP and it’s ilk "spoils the cow’s milk". I would never think to alter the eq of what the producers in the studio intended.

I do tend to agree with the legendary Floyd tool though is that EQ in the mid and treble may spoil the entire reason you picked your speakers to begin with but if you are adding a sub, you are adding a tone control. That’s just facts. You are already outside of the pure, well disciplined land of hifi purity and the goddess of music and all things holy will no longer show you her face. We are already damned.

What EQ gives you, and DSP in particular, is the ability to control big room nodes which can add 20dB or more to the bass in narrow peaks. 20dB is 100x the power at those spots. In the example on my blog the room nodes are a lot less pronounced but when I had those issues they were awful and EQ was the difference between using a sub or not.

Having been spoiled by measurement equipment, and hearing and reading stories of audiophiles attempting to integrate a sub or speaker to a room without it, I simply cannot imagine attempting the process by ear. Life is too short.