Mostly it's just the bass itself! I used the bridge pickup and had full volume and tone. I use Ernie Ball slinky bass strings on my basses. I guess a part of the punchy sound comes from the pickup placement (different compared to e.g. a jazz bass). Also using EQ and compressor to bring up those bright tones helps.
Great playing and pocket ! I noticed something, its not an issue with your technique because it does not sound like this in your other videos, but i think your 4003 has the pickup slightly too close under the G string, it sounds too crisp compared to the other notes. If you want to try, you can lower the pickup only on the G string side even by 1or half turn of screwdriver, in my experience the pickup height is very important (:
