Porto. From a life long Tannerd & former user of both preamps.
Chatta. Say what? A little bit better?....surely you must be kidding here.
Have you heard both products side by side in your own rig?
I will be blunt and to the point : There is just no comparison here whatsoever. The ARC sp-8 is in a completely different leaugue altogether regardless of model revisions.
If you are into vinyl.... the Luxman's phono stage is a joke by comparison [a bad joke for that matter].
The ARC's line stage line stage is no slouch either and still competetive with many of todays better tubed offerings.
Not to mention ARC's service and support is top shelf.
The SP-8 was a breakthrough product in it's day,and surely destined to become an all time classic.
The Luxman CL-35 MK3.....Forget about it, mediocre at best. My original [unmodified] CJ pv3 bettered it in every which way.