Is headphone listening a primary or backup for you when listening to music?

I have a pretty good dedicated headphone listening system that I put together specifically for relaxation and critical listening sessions that I use 90 plus percent of the time. 
 

@soix, “I’ve got both, and while headphones are nice they cannot put performers and performances viscerally and as big and spatially in the room like a home system can — not even close and not substitutes at all”. 

 I think that there’s a difference between viscerally feeling the music that one’s listening to and when one is listening through a really good headphone setup. The cost to be able to hear micro details in recorded music with speakers means you either have to be driving a lot of air, or you’ve spent several tens of thousands of dollars to even come close to the detail retrieval of many top tier headphones on the market today. 

I think that there’s a difference between viscerally feeling the music that one’s listening to and when one is listening through a really good headphone setup. The cost to be able to hear micro details in recorded music with speakers means you either have to be driving a lot of air, or you’ve spent several tens of thousands of dollars to even come close to the detail retrieval of many top tier headphones on the market today. 

@adasdad You can talk about micro details or moving air or whatever, but headphones just can’t do what a home system can — it’s just physics and they’re very different listening experiences.  Apples and oranges.  And it doesn’t take all that much money to put together a very respectable home system with plenty of detail that can physically place visceral images in a large 3D stage these days, and headphones just can’t do that no matter how much you spend.

I listen to headphones about half the time. I have Stax 009s, Audeze LCD-X, and Audeze LCD-XC. I really like the Stax phones but I have to fire up the tube driver amp (Stax SRM T1S) and wait a bit to hear them at their best. It's just so easy to grab the Audeze phones and listen through my Benchmark DAC1. 

@soix – I think we are actually agreeing on the physics, but talking about two completely different types of ’detail.’

You are talking about scale and acoustic presentation—the physical projection of a 3D stage into a room and the visceral feeling of moving air. You are 100% correct that headphones cannot replicate that specific physical sensation. It’s a totally different presentation.

But I am talking about pure information retrieval and resolution. Dollar-for-dollar, a top-tier headphone setup completely removes the room’s acoustic reflections, standing waves, and ambient noise floor from the equation. It allows an ultra-lightweight driver positioned millimeters from the ear to resolve microscopic micro-transients, subtle vocal textures, and low-level ambient decay trails that are physically masked by room interactions on a speaker system.

To hear that exact same level of microscopic texturing and black noise floor through a pair of speakers, you have to spend an absolute fortune on advanced room acoustics, ultra-low-distortion amplification, and flagship transducer engineering just to pull those tiny details out of the room’s noise floor.

It really is apples and oranges: speakers give you the grand, visceral scale of the concert hall, but a reference headphone chain acts as a high-powered microscope for the actual recording tape.

It's backup for me or an alternative if my wife is sleeping.