Musical Fidelity X-10 Tube Buffer Stage

I used the old one in an old system and it did not float my boat.

Technically speaking it's a dual triode set-up in differential connection for each channel making it two dual triodes.
A differential connection is a stage with 100% feedback.
This device simply makes an output more linear in any output you use.
Depending on linearity of the output of the source device this unit will or will not bring a substantial difference.

My system is getting closer and closer to nirvana, spoiled only by a slightly fatiguing high end which I usually suspect is the CD player.

Is anyone willing to place a bet on what this would or would not do in between my SCD-1 and ARC SP-11 Mk II preamp?

Cwlondon,
I bet you can patch it at the pre main output for the best results.

Decware makes an item like this as well. It's called the ZBOX. I just bought a phono stage from them on a 30 day trial and saw the ZBOX while surfing their pages. I used to own the X-10 and it worked well with my Quad 77 CDP. When I upgraded my digital components I found I did not need it anymore.

Some differences I noted in the ZBOX include the use of a 12AX7 tube mounted externally so you could tube toll with it. It also has an IEC so you can use an upgraded PC if you like. The X-10 uses a wall wart, something I wasn't crazy about. The MSRP on the ZBOX is a few hundrd more, but Decware is offering an intro price of $399, same as the X-10. 30 day trial applies as well. I'd give Steve Deckert a call (his number is listed on the site) if you need more information. Might be worth a test drive.