VTL 6.5 vs VTL 7.5

How much difference is there between these two preamps? Is the 7.5 quite a bit better sonicially than the 6.5?
Power supply is removed, thats about the main difference. But you should find out if there are any sonic differences from the VTL. My understanding is it is just the power supply being in it's own chassis, which is a big deal sonically speaking.
Also a different grade of caps in the 7.5 as compared to the 6.5 and the 7.5 I believe has a sort of floating circuit board where it is somewhat decoupled from the chassis.

7.5 is tops.
I would do the newer 6.5 mk II instead of the older VTL 7.5
Very few differences

(1) Output coupling caps are smaller on the 6.5
(2) 6.5 uses unshielded relays; 7.5’s are shielded
(3) Of course the 7.5’s power supply is physically separate.

Luke Manley claims that the 6.5 delivers 85% or more of the 7.5 sonics – very, very close.
I am trying the 6.5 now...latest version...might consider the 7.5 mkII...is it worth the difference....I have put some NOS tubes....seem to make a significant difference...clear top RCA...also some GE 6189W mil spec....and some Sylvania tubes...working my way thru them....any suggestions?

I auditioned both of these preamps and went with the 6.5 MK II. There simply was not even close to a $5k difference in the sonics of the two. Maybe if you had some super revealing stuff downstream, you could talk yourself into the justification of the extra money. In my case, I used the savings to buy interconnects and source material. The 7.5 has a bit of additional slam, but it was subtle, at best in my experience. Re. using nos tubes, VTL ships the 6.5 with NOS GE tubes. I assume they do the same with the 7.5, at least in the audio chasis. I experimented with some NOS Mullard/Blackburn tubes which I found to be very sweet, but perhaps, a bit soft. I've now replaced the Mullards with some NOS GE Broadcast grade tubes that make the unit really sparkle!