Is it possible?

I was inquiring about a DIY preamp of commensurate quality to a Pass Labs and got a response from Wayne;

I would run a 250.5 balanced. The BA 2018 boards are done now in a dual version so it is easy to make a balanced pre.

I would still like to go this route and have a different question. I ran across a Pass Labs XP-20 at a price I could not refuse. I bought it thinking I could use it while I am building/perfecting the BA 2018 based preamp and could use it for comparison.

The question is, if I build an all out version of the BA 2018 based preamp could it equal or possibly surpass the XP-20?

By "all out" I mean separate power supply and best available components and build methods.
Thanks for the input. I hoped to get the unvarnished facts. Actually I hoped that it was possible. LOL But better to have the facts than to chase a ghost.

I have not heard the XP-20. I did hear the X-250.5. It was with an XP-12 preamp which has a toroidal design transformer with both an electrostatic and Mu metal shielding along with vacuum impregnating and epoxy fill. I will use a similar Xformer.

I have built a Pass Pearl II and am very pleased with it. The ZYX Omega X type (cryod crystal copper) low output. 0.24 mV. with the SB2 silver base cartridge may have something to do with that. I will be building a power supply for the PP II later this year. If I can get permission from my collaborator I will share the design here.
..... Actually I hoped that it was possible. .....

actually , it is possible ...... either building something similar or dissimilar , strictly speaking of SQ

though , to be able to do that , one need to be of kind not needing to ask exact question in forum

so , you're (still) in great position - you can buy one , use it with great joy ...... while having enormous fun building whatever you want and can
They can both sound good but the BA 2018 I did isn't quite there. Our commercial product gets a lot of attention to detail and tweaking for the sound we want. You can do that with DIY but it is time and money. DIY you get the fun of building and the particular sound you want.

I think this is super important. Especially with a circuit like an xp-20. Tons of time spent getting things just where Wayne and Nelson want them. We diy-ers are just happy when we get a circuit to work.

Simpler power amp designs like an f5 or non-super symmetry or x designs are a little easier...throw a bigger, better transformer in there and some more/better caps and they can sound better than the commercial versions. Expecially with more bias. But the preamps have a lot of voodoo in them and are more complicated with regulation, volume control, etc all playing a role.

But luckily we can build lots of amps/preamps and try them all out and see what kind of topologies/designs we like. That’s the real beauty of DIY...the ability to try things and understand what we like and don’t like.