Should I eliminate my preamp?

It all depends on the preamp!

Happy Listening.

However, since the OP has all the tools to do the test for himself, he is best to answer his own question.

+1
I have always found that if you have enough gain for the loudness level you want or need, then going direct (with no preamp) has always been the most transparent, dynamic, least coloured way of listening to the source.
So long as the source is not a tube output, which can be high impedance, then you may get a impedance mismatch to your amp.

Nelson Pass made a preamp he loved called the Aleph L, which is passive until the volume control get’s to 3 o’clock, after which an active stage come in if you need more level, but as he says at a detriment.

Nelson Pass: " At the 3 o’clock volume control position, the Aleph L offers a direct path from input to output.
The only component in the signal path is wire and switch contacts.
At positions below 3 o’clock, the volume control functions as a precision passive attenuator using discrete resistor ladders.
Above 3 o’clock, active gain is added to the output signal in 2 decibel increments, for amaximum of 10 dB.
As a result, you suffer the effects of active circuitry only when additional gain is necessary."

Also a Nelson Pass quote:
" We’ve got lots of gain in our electronics. More gain than some of us need or want. At least 10 db more.

Think of it this way: If you are running your volume control down around 9 o’clock, you are actually throwing away signal level so that a subsequent gain stage can make it back up.

Routinely DIYers opt to make themselves a “passive preamp” - just an input selector and a volume control.

What could be better? Hardly any noise or distortion added by these simple passive parts. No feedback, no worrying about what type of capacitors – just musical perfection.

And yet there are guys out there who don’t care for the result. “It sucks the life out of the music”, is a commonly heard refrain (really - I’m being serious here!). Maybe they are reacting psychologically to the need to turn the volume control up compared to an active preamp."

Cheers George

I’m confused. As you have listened to the system both ways surely you are best placed to know the answer?   It's like asking "I have a Californian and a French red wine, both of which I have tasted before.  Which tastes better?"

I just travelled this road.  The direct from DAC was clean, extended, with great dynamics from lower mids down.  Things like Neil Young at the Cellar Door sounded live, and bombastic things like Emerson Lake and Palmer sounded bombastic.  No listening fatigue.

Then Karma stepped in.  A friend sent an email saying he was downsizing and selling his system.  Amid the pieces was his totally rebuilt Audio Research SP3.  I tried it and was amazed at the difference. Voices were illuminated and compelling. Joni shimmered.  Percussion sounded like wood and membranes instead of thuds. Performers I thought I knew sounded more three-dimensional and nuanced.  The difference in soundscape from album to album was surprising.  I was entranced by what I heard, whereas the direct link presentation was far less captivating.

But I lost "bombastic" and the lower frequencies were softened on the SP3, probably because there was insufficient room for larger caps in the rebuild, and that rebuild was done quite awhile ago.

I was so convinced that I searched for the right linestage.  I could find nothing but praise for ARC REF 3 linestage, so I'm spending a lot of money I didn't intend to.

My schooling and career was about logic, and logically the direct link should be best, and that added piece shouldn't be able to add something that wasn't there before, but this is about experience and emotions, and logic only takes you so far.

I have had the same experiences as electro slacker.  There are times when a certain preamp will add a magic to the sound that isn’t there with the DAC/source.  Just like I mentioned above, a preamp is a tool that can be used to help shape/tune the sound.