Does anyone have any advice on scales or intervals that create a sort of gravely sound? That's the best I can do to describe. The only thing I've been able to do to create that sort of sound is use the Harmonic Minor scale.

Here's an example of what I mean, in guitar tab, I'm sure you've all heard this before, I'm talkin' about creatin' somethin' similar. This is in the key of D Harmonic Minor:

E|--------------------------------------------------------------
B|--------------------------------------------------------------
G|--------------------------------------------------------------
D|-----3--3--3-3--5--3-3--2--2--3-3-----------------------------
A|-----5--5--5-5--7--5-5--4--4--5-5----------------------------
E|--------------------------------------------------------------

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