Any suggestions for ear tips that doesn't bury the bass?
The stock eartips have tiny bores that putting them on is next to impossible. The ones I were able to get in (including the default white with black stem and white with yellow stem) were mostly on the bright side without much bass.
I've tried the SednaEarfit and it doesn't go deep enough to get a good seal so not only do I lose out on everything, I had to adjust the volume by 10-20% than when I got the stock tips. Or maybe I sized wrong because I bought the small one.
I am not sure what you mean by bury the bass, but the wide-bore tips tend to tighten up the bass for better texture, at the expense of big boom, whereas the small-bore tips tend to do the opposite (make it boomier, at the expense of texture). So, I guess it is up to your ears as to what sounds best with these. Keep in mind the wider the bore, the brighter they will sound. The small-bore tips also decrease the treble a bit. Also, keep in mind that if you are wanting the bass to be prominent, and to tame treble, putting a pure copper cable will also do this for you.
If you turn the umbrella part inside-out, then hold the bore at the top (near the umbrella), and press them on, starting at an angle, it is not too bad. If you get most Spinfits, you will need to do this trick.
If you feel like a tip is not going deep enough to make a proper seal, chances are you are probably using a tip that is too small (not enough taper to catch in your ear). It is a good idea to try all sizes, even if you think it won't work. Because not all IEMs need to go deep into your ear to make a proper seal (though some certainly do). I have a pair of iBasso IT07 that CAN be inserted pretty deep and seal well, but I can also set them at the outer part of my ear, and the IEM will sort of fold upwards on my concha to hold them in place, and they are totally sealed off. All IEMs are built differently, and just because one tip works for one IEM, that doesn't mean it will even come close with another IEM.... A couple of IEMs I have the Final Type E tips are the absolute best, but for some of my others, they are complete trash. All this from my experience, and YMMV.
Edit: That being said, I have found the right size Xelestek, and Spinfit CP100+ and CP145 to work very well with the Timeless. Again, YMMV so experiment. Also as
@holsen keeps preaching, make sure they are conditioned for a long time. While this won't change the sound signature, it will tame those peaks and areas that are rough in the beginning.