The first Led Zepplin album, is still a vivid memory for me...we used to hang out and listen to it a lot. It really was a shock to me as a bassist...how funky bass playing could fit into heavy hard rock music. Rick Danko was the other bassist that did so at the time. JPJ WAS Led Zepplin's mastermind, even though they were all great players. His sound.. I'm reasonably sure they weren't using Acoustic 360's in England in 1969. At least not in a recording studio. He is using a Jazz bass, more than likely...possibly the old P-bass with the tele- style headstock too. Flatwounds! Roundwounds were still in their infancy here, maybe less so in England, but he was a veteran session bassist- traditional tone and feel were something he was accustomed to- This is an important part of his tone...and who knows what set of flats he had on there.
When bands of that era played out live, there weren't very many large amplifiers to choose from. In the U.K., Marshall, Hiwatt, Vox, Sound City, and other amps were originally 50 watts, and the old bass heads were 100 r.m.s.! By today's standards barely adequate for a small club gig! Here in the U.S., we had what? Fifty watt Fender Bassmans, and 100 watt Showmans, early 60- 100 watt Sunns, some early 100 watt Ampegs, and what was imported from Britain, I had a Marshall Major 200 watt head and a 4-15 cabinet, got it in 1971. The live backlines started using the higher powered tube amps like the Sunn 2000S and SVT ampegs right around that time- seems like 1969 is the key year here, I had a '69 SVT head, I think it was one of the first made. Legend has it that The Rolling Stones commissioned Ampeg to produce those amps for their touring backline. The Acoustic 360 was one of the prominent amps in the Woodstock concert, seen in footage, and heard on some of the famous tracks from that concert. I, personally remember hearing some of those live recordings thinking the bass sounded, well, distorted. It may have been operator error, or faulty electronics, but I do remember that. All the 360's I've played, and there were a lot, in backlines, rehearsal studios, and friend's amps- were good amps if you weren't standing too close to them. I also feel that they sound quite different from a 370-371 rig, also an amp I'm quite familiar with. P.S., I own five folded horn cabinets currently. I love them. The live Zepplin stuff I've heard imho, isn't the sound, or the playing/overdubs and production quality from the recordings...so, therefore...can a really good 'modern' rig, a good Fender jazz bass with flatwounds, and a strong player with a keen ear for tone approximate JPJ's studio sound? I also have and use- played it at an outdoor show today- an Acoustic B-200 combo...an Acoustic in name and appearance only. I really like tha amp, but its not the American made product from the 60's and 70's. I also had a 450 head and a short 106 cabinet with Altec 421-8h's, maybe the best 2-15 I ever had.