I have 45 hours on my new PH-8. So far, all I can say is WOW! According to the factory, full break-in isn't reached until 600 hours. The PH-7 with the power supply upgrade was my previous phono. Compared to the 7, the 8 is in a different league altogether. WAY more life-like. More life, punch and a more up-front perspective. Still has that ARC sound staging we ARC fans all like ... with, like I said, way more life. I'll report back when it hits 100 hours or so.
And how do you feel about the PH-8 now that several months have passed?
Just bought a refurbished PH-8 from ARC. The hour counter reports over 800 hours on the tubes, so I assume the unit has reached and passed the break-in point. I admit that the unit has been on for only 30 minutes, but here's my thoughts about the PH-8 compared to the PH-7.

Regretably, I do not share Oregonpapa's initial reaction. Don't misunderstand me -- the PH-8 is a fine sounding phono pre. But is it in a different league than the PH-7 (w/power supply upgrade)?? I'm not there. Is it hands down better?? I'm not there either. Maybe my PH-8 needs to warm up a little more. As I said, I think it's already broken in. We'll see.

If you check my System description, you'll see I'm all ARC, and recent gear at that. So I don't think my equipment is the bottleneck.

I'll report back in a little while about whether the performance changes. But right now, the PH-7 (w/ power supply upgrade) is absolutely no slacker, not by a long shot!! My advice is you won't go wrong with the PH-7: it's a fine performer.

I felt the same way about the Ref 5 compared to the Ref 3, but nobody likes a buzz killer. I actually have some misgivings about the new ARC gear in terms of really offering significant sonic improvements over their immediate predecessors. Have to say I also have come to believe that my Magnepan 3.7s aren't really that much better than my 3.6s were. These observations typically don't gibe w/ the tenor of forum conversation however.
Compared to the 7, the 8 is in a different league altogether. WAY more life-like

Yes, ARC is one of those companies which is able to improve each unit dramatically after a few months. Really great Design for years and years ...
Sorry Syntax, not sure I pick up on your drift. Do you concur with Djcxxx and me, or do you have a different view.

Btw, I left my PH-8 on all night and listened the next day. No question now about warm-up. Here's my updated reaction. I think the PH-8 might (??) have a lower sound floor than the PH-7. As a result, I think my vinyl playback has less hiss and noise. Does this relate to the PH-8 or wishful hearing, I don't know. Nevertheless, overall, I still think the PH-7 and PH-8 are cut from the same sonic cloth. And I am not convinced yet that the PH-8 is worth twice the price of a mint used PH-7.

Btw, btw, I called ARC to see if there's something else going on that needs a tweak, or if I need the services of an audiologist. Should hear back next week. If I learn anything worth passing along, I'll share.
OK, are you guys using the new power tube offered by ARC in your PH-8 and Ref pre-amps? If not, you should order one. Its a simple upgrade that significantly lowers the noise floor, improves the bass and increases dynamics.