No deep bass or highs: VTF or VTA issue?

If your XV-1s is fairly new, I would suggest running it around 2.1 grams or so for the first 100 hours or so, and keep the arm level. Mine is a few years old now. I usually run it between 1.87 and 1.93. My arm is just slightly tail up. Nick Doshi set the loading for my XV-1s at 100 ohms when he built my Alaap phonostage. This cartridge definitely does not sound dark through my system. It doesn't sound any brighter or darker than a ZYX Universe I have also heard in my system.

It was my Rhea that Swampwalker heard, or at least one of the one's he heard. It was rather bumped out in the mid-range, with the lows and highs seeming to be held back or rolled off. Noisy as well. To be fair the Rhea I owned was from the first year or so of that model.

Madfloyd, if I understand your original post, this bass issue started when you added the capability to your system to reproduce frequencies from about 60Hz on down. I'm assuming that when you say you have "dialed in" the sub using your music server. (I hope those are lossless formats. ;-) ) I assume that means that you have the sub crossed in around 60-80Hz. That is well within what your vinyl rig is able to reproduce if set up properly. No news to you here since you've already started looking into this. What I can't say is how your VPI setup should sound from my own experience.

Damping fluid is usually applied to focus bass but using too much can also detract from the upper frequencies. This could result in the loss of air you mention. Too little could result in little or no weight to the music. I experience this with my Vector tonearm when adjusting damping.

As an outside observer I notice that you seem to be making large swings in your settings. IME that means it is very possible that you are skipping over the sweet spot. I would suggest trying to go back to a very neutral starting point. Level tonearm, around 1.9 VTF (assuming a broken in cartridge), little or no AS, damping fluid at the VPI recommended level. Listen and make very small adjustments from here, but remember that changing one parameter will affect another so go slow. Listen some more. I think you know the drill, but leave the fluid alone until you have determined that you really are getting closer to what you want to hear.

If you add a bit more fluid, I'm talking a few drops at a time, and bass impact improves then try backing off the VTF just a little, a few tenths of a gram, to see if the HF reproduction improves. If you remove a bit of fluid and HF improves, then try adding a tenth or two of VTF. This process of finding the best fluid level can be long, drawn out. Think days and weeks, not minutes and hours.

However, if you are not hearing any bass impact or air from this neutral position then I think you need to realize that there may be a limit to what your table and arm can do. It doesn't sound to me like the cartridge (assuming it is healthy) or any other components are in question. For any given combination of CDP and turntable it is entirely possible that one will outperform the other.

Also, I don't think you have mentioned where and on what your table is sitting.

Here is a link to a white paper that another A'goner referenced several days ago. I think the concepts presented in this paper will help explain why your theory of what large changes show is full of holes. So don't despair yet.

Vacuum State GuruSetup

What you describe as shimmering from your digital source is, as Piedpiper points out, not correct. I've used that term incorrectly myself so I'm not sure I understand exactly what you are talking about. Shimmering implies something is being added and is most likely an artifact. What you want is that strike and long decay from cymbals. I'd be curious to compare your music server to a decent redback cdp.

At the same time I think I understand what you're saying about the cymbals on Deacon Blue's. I'll pull out my copy today and get more familiar with your reference.

After playing Aja again, it's been a while, I can understand why you may think it sounds dark. That album sounds like that to me all the way through. But I can confirm what Dre posted about the cymbals in the beginning of Deacon Blues. Plenty of decay after a whack and the next whack comes before the decay ends. It is continuous but the individual cymbal whacks are very discernable. I don't have CD copy of Aja so I can't compare. I suggest double checking that you are comparing the same mastered versions of that album. Even then the digital version can sound different than the LP.

I've not heard of anyone tracking an XV-1s much below about 1.9, but Doug is right. Not only are cartridges different but so are arms, etc.

a good digital source/recording almost always will be better ( quality/quantity )on bass than an analog one

Not my experience at all, but we certainly use different system components and hear differently.