And you see where that's gotten you, right?
I listened to your examples ... and your bass guitar sounds like someone recorded his bass in a vaccum, with no thought as to how it was going to fit in with the rest of the mix.
Then you came on a recording board and asked for advice as to why your bass sounds good in solo mode, but doesn't work in a mix. And now you're resorting to dramatic use of EQ to try to make it fit.
This is a very common thing, and it happens with everyone on this board (and outside in the world) at some point. Bob, I'm not trying to put you or your recordings down. To the "layperson," as you put it, your stuff sounds fine. But if you ever find yourself interested in taking things "to the next level," ... then you're going to have to start listening critically earlier on in the process. Think about tracking in such a way as to make the mixing job easier. Then mix with the idea of making the mastering job easier. Use everything at your disposal to get your tracks 85% of the way there ... so that come mixdown, you only have to use some modest EQ to get you the last 15% of the way there. This means little things like changing your strings, and yes,
playing with those dials that God put on your guitar,

changing pickups, and even trying pick versus finger. Then listen to how these changes work in the context of the rest of the mix before you even lay down a track.
Once you get to the point where you're listening to your track over the monitors ... and making critical adjustments, while you're tracking, on the fly that you feel will help your track fit better and save yourself extra work / processing further down the line ... then you'll be taking your stuff to the next level. This isn't easy to do, and it requires you to put on your mixing hat a little earlier than you might like. It takes a lot of time and work to get in that mindset. But if you're happy being just "above average" ... then by all means, disregard everything I've said, and keep doing what you're doing.
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