In that Japan 1978 amp photo above there are 6 amp heads hooked up and 3 that are not including the 50 watt heads.
3 amps = amp setup number 1 = main setup
3 amps = amp setup number 2 = Eruption/backup setup
3 amps not hooked up = amp setup number 3 = last resort backup
2 variacs, one each on the main head in setup number 1 and on the main head in setup number 2 with the other 2 heads in each setup daisy chained to the main variaced head.
2 Echoplexes, one on amp setup number 1 (main setup) and the other on amp setup number 2 (Eruption setup).
Ed always has a backup everything this way. If a Echoplex goes down he can switch quickly to another amp setup and still have a Echoplex. If a cab blows a speaker he can switch quickly to another amp setup. If a amp head blows he can switch quickly to another amp setup.
So Ed has 3 daisy chained 100 watt heads for his stage volume in both amp setups (amp setup 1 and amp setup 2) which is then miced for the PA.
The actual details vary a bit (from my pedalboard thread) from what Ed says below but not by much and Ed is not the best explainer out there.
"EVH: What I basically have is three different setups, three complete setups. I have three 100-watt tops of whatever make – right now I'm using Music Man, a couple of Laney amps, which are English, and a couple of new Marshalls. I'm just using everything right now because I lost those old amps. But I use three 100-watt amps for the main set – what I call it – and then I do my guitar solo, and after that I change guitars and amps to setup number two. Setup number three is also again three amps, for backup.
Guitar.com: So you have each guitar . . .
EVH: Plugged into a different setup. So if something is wrong with the first one, all I do is grab another guitar, and it's completely different amps. So I don't have to worry about trying to fix the setup that I was using. I got so many different heads. I just gotta patch 'em all together and hope it sounds cool. It's working out pretty good. And I use the same style guitar. I use one pickup in the back and the vibrato. That's the sound I'm into right now. Who knows what will happen on the next record."
"I just gotta patch 'em all together and hope it sounds cool." = daisy chained together.
At the end of a daisy chain there is only one lead going into the final daisy chained amp.
So Ed has 2 daisy chain inputs and 2 daisy chained outputs and each daisy chain consists of 3 amp heads for two 3 head daisy chained amp setups. One main 3 head amp setup and another Eruption/backup 3 head amp setup.
So there should be 2 amps with 2 input leads (red arrows) and 4 amps with one input lead (green arrows) and the two Echoplex leads (blue arrows) go into 2 of the amps with one lead and the two 3 amp daisy chain setup is complete.
Two lead daisy chained amp head.
Two Echoplexes with the same settings. One Echoplex on the main amp setup and another on the Eruption/backup amp setup.
Having two Echoplexes with the same settings in series is pretty pointless.
