Upgrade from Levinson 335. Which amps?

I can describe the sound from the current system as open, clear, and airy. I think the sound is pretty close to neutral, but some might say the sound to be a bit on the leaner side. I would like a bit more body and substance in the sound, maybe at the expense of some of the openness. I prefer SS over tubes, but I'll consider both. Some of the amps I am considering are:

Pass Labs XA-30.5
Spectron Musician III SE Mk2

Rest of the gears: Linn Unidisk SC, Focal 1037BE, no preamp.
Get a preamp first, preferably something with tubes. I owned a unidisk SC and a Levinson 336. The problem is not the amp.

Just my honest opinion.

Good luck.
I agree with Jim above, the 336 has plenty of body and substance. I use a BAT vk51 se preamp with my 436's (previously owned a 332) and Mac 501's and its super. To me your issue is the Linn, which I feel would be the lean component in your system.
Thanks for the suggestions on the preamp and the front end, but perhaps that's for another thread. Let me rephrase the original question. Has anyone compared any of these amps?

Levinson 335
Pass Labs XA-30.5
Spectron Musician III SE Mk2

I'm curious which amp could produce meatier sound, like more chests than the vocal cords for vocal recordings, and more woods than the strings for string instruments.
Hello Jylee,

I have heard the BAT 150se and the ML 33H in the same Avalon Eidolon based system and textures were certainly more fleshed out and more dimensional with actually an increase of air with the BAT 150se. Hope this helps.

Preamp is your problem. You need a preamp. The 335 is a very good amp and better than the rest of your gear. Out of all your gear I would sell the 335 last.