OK, so, this thread was about Duff's sound right? So, I myself have said he recorded appetite with an 800rb, But that might not be true. He said he bought the GK head from guitar center with his advance but it's not for sure the 800. He said he started with the 400rb then got the 800 which he used on the tours. I believe he first got the 400rb. Before their advance he was using stuff like Peavey. Check out the reckless road book.
Duff said he used his GK into a 2x15 cabin with EV speakers to record appetite and same for illusions. I have an 83 400rb into a 2x15 EV cab and with the right bass it's Duff.
It is the GK sound, but make no mistake if the bass and esp pickups aren't right, it won't get it. For example, I have 2 basses with the harness from the Sig Duff bass. One has a plywood body (old Kramer) and it sound good but not quite there. The other bass is a fender with the Duff harness (P&j) and it nails the sound. These basses have roto 66 on them and at home I use an 87 800rb into a genz Benz 2x15. Now, I plug my regular P bass, my active emg bass or my Thunderbird basses and the sound is gone. Seriously, my $1000 new bass won't get that sound nor my old Thunderbirds. I assure you the bass, esp the pickups are very critical to that grindy sound. Another example, I had Duncan 1/4 lb P&j in another Kramer, great pickups but nope, wont get it
Duff don't didn't use the 2001 head, mxr, woolly mammoth or anything other than chorus until after his gnr days. He used that Yamaha spx 90 but also many different chorus pedals over the years. I've owned the corona w/ Duff toneprint, wasn't impressed.
So you want Duff tone, get an old fender jazz special, pop in a Duncan STK 2 for the bridge, fresh rotosound 66, GK 400or 800rb into a 2x15. 4x10s are OK too but it won't be the same. Pick gauge isn't so important but I do feel that the ,73 does make a bit of difference over my usual .88
FYI, I have no idea why that had a huge banner of Duff @ the GK booth at NAMM, HE SWITCHED to a fender baseman 300 and also that micro gks when GNR got back together.