Headphones vs speakers….

The soundstage is badly distorted on headphones; Pure left sounds only to arrive at the left ear, and are perceived as being way to the left, with nothing on the right to create a semblance of a credible space. Likewise on the right side.

Pure left sounds on speakers also reach the right ear and they are perceived as being on the left side of a stage, far more realistic.

Sound from speakers at an identical left and right level, say, a vocalist or lead instrument, iff* you are seated exactly the same distance from both speakers, will deliver a nearly convincing center image - except that, again, there will be sound coming from the left speaker reaching the right ear and vice-versa, so that center image will be poorly focused at best, and only to a person sitting directly in the middle. Anywhere else, the center image fails. Try this: play a tune with a vocalist singing in the center - sit right in the middle. Now hold a record jacket, edge to you nose, blocking the left signal to your right ear and vice-versa. You will immediately hear the singer pop into focus, more accurately and realistically, coming from the center.

With headphones, a sound at equal levels left and right will be solidly placed in the center. Also, headphones will be immune from room resonances and reverb.

So - which is better?

For critical listening, for just one person, I would say a good pair of headphones - with one important condition: Unless the musical source is binaural - and that can sound spectacularly realistic, you need to temper that exaggerated soundstage.

It’s not too hard to do.

You need a separation or blend control to narrow that space. On some recordings, like some early stereo, where there was an exaggerated separation for effect, that will make the music far more enjoyable. But I find it essential with just about any stereo source.

It could be as simple as putting a 5 to 50 Ohm variable resistor (depending on your cans’ impedance) between the left and right wires the headphones.
I have adapted a few cables with this simple mod.

Then you can dial in exactly what you perceive as a natural sound stage, and the center will always be far better focused than any pair of speakers can ever hope to achieve.

You will be amazed how much better headphones will sound.

* iff - that’s not a typo. Look it up.

All in all I’ll be needing the system and headphones - the headphones for when I’m out and the system when I’m home. I understand these will be different experiences. Since my system isn’t properly set up yet I’m simply curious as to what to expect after being very very happy with the headphones. From dabbling with the temporary integrated I’m using now and the (probably) badly paired speakers I know a lot of my disappointment is due to the mud coming from an untreated room compared with the spectacular clarity of the headphones. These Totems are tiny but probably perfect for a small room like this but the mud I’m hearing when I swap them out (175mm cones compared to 125mm cones) really sound awful in this untreated room at present which has me wondering if I’m going to be able to use a subwoofer in that room. Anyway, I’ll find out in a couple of weeks once my Benchmark DAC3 arrives to complete my Benchmark setup.

This will be a dedicated listening room - I’m planning on hanging thick curtains on three walls (behind the speakers and both side walls) to dampen echoes - is this advisable? I’ll have the curtains cut into sections that I can open at intervals if need be to experiment.

The soundstage in the RAAL SR1a is like 2-channel not like headphones. That is the one of the beautiful aspects of the sound thorough them. Checkout this review below where the reviewer says he disliked the SR1a because people laughed at him and that they did not sound like headphones. 2-channel people should really hear these because a perfectly optimized SR1a is hard to beat with a 2-channel speaker system.

(3) What's a RIBBON headphone? RAAL Requisite CA-1A Review with Resolve! | Headphone Reviews and Discussion - Head-Fi.org

I agree with @yyzsantabarbara above.  I too have a RAAL SR-1b Nearfield Ear Monitor (Earspeakers) system and they are the closest thing to the experience of listening to loudspeakers in a room.  Of course, in my mind the gold standard is a live musical performance in a performing space but both speakers (I have had many speaker-based systems in the past) and headphones both have their merits.

I love headphones for the same reasons already mentioned this thread but still prefer listening to speakers despite their faults. I think it’s important to have a sound wave actually traveling across your head, with the driver far enough away from your head that your head doesn’t become reactive with the driver. The ear and the driver are best acoustically uncoupled to create externalizing effects. With software it is possible to simulate the effects of sound waves traveling across the head and outer ear to make an externalized sound field. I know the Smyth Realizer does this and Apple and others are starting to work on it too. I haven’t heard these technologies myself yet. Occasionally I’ll get a startling effect on headphones that tricks me into thinking I’m hearing something far away so I know it can work. Another issue though is it’s more comfortable and relaxing to not have things on or in my ears when I’m in the comfort and relative quiet of my home. When traveling headphones can block noise and sometimes keep ears warm so they make sense on multiple levels. I might wear them even if I’m not listening to anything. One thing that amazes me is just how noisy a car interior can be on the highway. It’s mostly bass rumble and that becomes apparent if I put on headphones that don’t block or cancel noise. I turn them way up and still can’t hear any bass!