If you want frontal presentation on your sub, you'll have to break some mindsets and ignore some forum folklore. Here's why.
1. Xover points: A decent pair of ears will locate source of sound above 70hz (appx). 120hz as suggested is way too high. So you're looking at crossing your sub and mids in the 50-63hz range. Put the sub and mid on the steepest slopes that you have. The sub because you want your mids stronger at 80hz and steep slopes on the mids cause they are rolling off sharply anyways around 50hz.
2. Blending: The next step is to blend your sub bass with your mid bass. 50 hz from your sub will be much louder than from your typical 6.5" mid. You want the flow back and forth between your mid bass and sub to be smooth. i typically level match from my eq +/-1 octave from the xover point. So I level match the 30hz-125hz range to get the right blend.
3. Time Alignment: Use your time alignment to connect your drivers. The sub with the mids and the tweets with the mids. You want to hear the tweets last, that will pull up your entire stage.
4. Kidney punch = Chest thump: Part of getting the sub presentation upfront is accepting that it won't be as loud as the kidney punch option. Balance is what you're aiming for. Balance for L/R if you can and across the sound ranges. One sound, unisource, sound totally disconnected from the drivers. What you lose as impact from the sub you make up by getting a solid impact across 20-20khz.
Hope that helps.
