New dac

I should add that part of my upgrade fever was what you mentioned—I was worried that DACs seemed to be improving so quickly. If I had to guess, I’d say the magic in the DL3 is in the excellence of its analog stage. PSA has been building superb analog gear for decades. 

If you're using usb I second the suggestion to try a reclocker. It will probably improve the bass and it is cheaper than buying a new dac.

Previously, I owned PS Audio Directstream..I should say, it was a very nice DAC for the price. I love it when they keep updating the firmware and each time, it gave me different sound flavor.

Later I sold it and replaced it with Lampizator Golden Gate which I really enjoy until today. Planning to update to Lampizator Pacific DAC in the next few months.

Check out this brand because they have many level of DAC which might suit your budget.

3rd vote for reclocker/regen on usb side. Wyred4 Sound Recovery can be had used for $110 and I think is better than synchro mesh, but it does lack ground plane isolation. The RuR as it’s known also benefits greatly from an improved linear power supply. You might start with an Audioquest Jitterbug for $50 new, with free return at musical fidelity which will fatten up the bass and mellow your treble. They can also be modified to cut the vbus power which is said to improve the sound. I’ve realized big gains by building an elaborate usb chain. The Bluesound is a well regarded but lower cost and modest usb source, and almost every usb source needs to be improved. Which USB cable are you using? Cardas can help with bass there as well (I use a v1 Clear), but I’ve recently heard great things about the iFi Mercury 3.0.

All that said, the AQ Colorado is a light/lean sounding cable to me. Kind of the AQ house sound, at least before the latest power products moved away from it. I think your Gibraltar is more neutral.

I’ve got a pair of 3A Sigs. I’ve found that most bass problems stem from speaker / listening position placement rather than component issues.

I used the ’odd dimensions’ method from the manual. Have you tried moving them around using this procedure? I also find that my speakers sound best without any toe-in. Try changing that aspect as well. Also try to measure how high your ears are from the ground. This would affect the cabinet tilt-back angle (and as a result frequency response).

You could also be sitting in a null in the mid bass frequencies. Experiment with moving your seat back and forth a few inches. You might find it makes all the difference.

Finally, you can adjust the contour controls. Try reducing the level of the midrange by 1-2 dB. This might give you the mid bass balance you seek.

Hope this helps!