The Pyromania and Hysteria albums took Def Leppard into the upper echelons of Rock artists like Foreigner, Journey, Bon Jovi and Scorpions. Their earlier albums were successful, but Pyromania produced more hit singles than any of their previous releases. Better songs, better playing and better production paid off in spades.
I have listened to the Atmos and 5.1 mixes of the new box, so far. (I'll get into the CDs later.) What I hear different between the two mixes is that the 5.1 mix is more front-centric, with the rear channels mostly used for duplicating some instruments with the fronts or in support of the front channels. (Do many of today's surround mixers think the majority of people with 5.1 systems don't have full range rear speakers?) You get background vocals, some drum bleed, etc., but rarely does an instrument show up only in the rear channels.
The Atmos mix on the other hand is incredible. There is full use, with discrete instruments, vocals and sound effects in all the speakers. I'm playing it in 7.1 (7.3 subs actually with "side channels" in the ceiling, in the back 1/3 of the room. Two more speakers in the ceiling in the front 1/3 of the room are fed by the processed center channel signal. Search for my post about "Frankenstein Atmos" for an explanation on that.) Both the 5.1 & Atmos mixes have good, solid bass. Like every other Atmos I have, you have to turn it up louder than the 5.1 or stereo mixes to get the same output. I'm guessing Atmos mixes are being done that way to reduce how much data is hitting the decoder at any given moment, especially on very dense or loud material. I don't mind that. I have volume controls on my amps... However, it seems like the levels of the various formats are closer on Pyromania than some others I have. (Maybe they turned down the 5.1 & stereo mixes? It would make sense.) This isn't one of those mixes where you have to turn it up to get the bass going like some other recent releases.
I agree that "Stagefright" does sound different than the other tracks in both the 5.1 and Atmos mixes. Not bad, just not as discrete. Was it to make it sound more like a "standard" live/concert track to go along with the song's subject?
That one song aside, I just have to say that the Pyromania Atmos mix is the best Atmos mix I have heard/own in any music genre. One thing I really admire (and hope more Atmos mixers start using) is that the center channel is NOT used for lead vocals 95% of the time. Instead, lead vocals appear in the front L&R channels to create phantom center placement. It totally works. You will swear the vocals are coming from your center speaker until you put your ear up to it. Well done. Instead the center is used for some leads, gang vocals (also in the rears and overheads), some percussion, etc. There are long stretches where there is not much happening in the center channel and then a lead will jump out. This is one of the first mixes where I can easily tell discrete sounds and instruments are coming from the individual sides and rear channels. I don't hear a single channel choice decision made by the mixer that I disagree with. All spot on and sound "right".
The next time I have someone over to the house that asks me, "What is so hot about all this surround stuff?", Pyromania in Atmos is what I will put on. "Too Late For Love", "Die Hard The Hunter" or any of the hits are just spectacular demonstrations of what a surround mix should be. This is a solid 10 all around - mix, fidelity, content, attitude, value.
(And in case you think I'm just a DefLep fanboy, I have to admit they are probably not in my top 10 favorite Rock bands, This release is just THAT GOOD!)