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

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.

@adasdad + 1

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.

@adasdad Agreed.  I was able to put together a HeadFi system that pretty much replicates the level of detail/refinement of my big rig for about 20% of the cost.  From that perspective it is a beautiful thing!