You look at it is n the wrong way. Maybe because you lack the knowledge what a miniDSP is doing for you.🙄
When saying:
very much doubt the DAC in a $250 device is going to equal my Aqua.
If we take one of the many things miniDSP is able to do. PEQ for example, so when you have measured your listening space at your listening position with your calibrated MIC ($100).💰
And knocked down peaks and the biggest problems of your room and downloaded the generated PEQ file to the miniDSP so it flatten and solve the biggest issues in sound quality at your listening position.🎶
Then the truth is that there is NO Aqua or ANY external DSP no matter the price that is going to equal the sound quality at your listening position as the miniDSP using PEQ.🥇
You are trapped in a false belief that oh only that if I got a better this or that. As I tried to tell you can keep doing just that whole your life without getting anywhere. But that is maybe something you enjoy more than sound quality? So please go on.🔄
Another point is, if your problem is "bass blom". And you look at the basics for what type of principal your speaker is designed with. In this case a bass reflex ported construction. That is time smearing and a bloomy design in it self..🌼
So you say dear Mr bass reflex do not be what you are and you should try to be like a sealed or OB construction please.. because you are so gorgeous and I want that you please me.🧙♂️
You need to look at what technology you are using. And those speakers are probably not for you when they do not please you. And do not try to make them things that they are not designed for. 🤔