Using ARC sound bar with ACE

Use subtitles. Once you get used to doing that, you will find a lot of movies that are in their original language with English subtitles that will expand your window on the world of movies. Dubbed to English, these never come across well.

To actually answer the question posed by the OP instead of offering unsolicited advice about expanding ones cinematic tastes, it was stated in the Ace thread that the Arc will be silent when connected to the Ace.  So I’m afraid the Ace will not work for the OP’s needs.

Using subtitles even if OT seems like good advice then 🤔

Or @ptate if you have an Apple TV, you can connect two pairs of apple headphones to it. So not ideal for your partner, it would allow you to both hear the sound.

When they say “A Singular Home Theatre Experience” they really mean it.

I would like to see the same feature, I have hearing issues and would not want to swap sound from arc to ace, but add the ace to it. I read somewhere they don’t use the WiFi on the headphones because it significantly reduces battery life, but if you are on your WiFi eco system your at home and can charge them easily. If charge lasts 30hrs, even if there is huge reduction I would assume that would still have plenty of life.

I would like to be able to do the same thing. No one seems to offer this (same issue with Apple AirPods and Apple TV box). It is my understanding that the reason it cannot be done is that there is an audio delay when transmitting sound via Bluetooth (a ¼ second or more) which would cause a disturbing echo effect if you were using the headphones while simultaneously having the speakers working as you would hear the sound delayed in the headphones yet the speaker sound would also bleed into your ears. This perhaps could be solved by using WiFi (Sonos Net) for the headphones like the speakers use. Guess Sonos was not smart enough to do that. They just came out with a “me too” BT headset like everyone else instead of making a truly innovative product. 

That’s certainly an interesting conclusion. What’s the evidence? I may have missed that in the product release data, but it seems odd that there would be a perceptible delay when the headphones are linked to an Arc. 

Again Sonos have released a product still in development stage as per the app.Better integration with the Sonos system would make these headphones outstanding ie allow sound from both headphones and  speakers simultaneously with separate volume level control battery limitations shouldn’t apply when used at home where the speakers are (surround setup).

Hopefully Sonos will take onboard customer comments and Ace gen2 will address shortfalls and set future headphones in front of the pack

Yes, I'm in exactly the same position. Having the facility to use the Ace at the same time as the Arc, via the app, would be an excellent feature for users with hearing difficulties who want to watch TV the same time as families. A family member with hearing difficulties with their own custom volume and Eq on the Ace and rest of the family on Arc soundbar.

As I understand, the Ace will connect via the Sonos WiFi network, as with other 'speakers'. If this is the case, it should be able to select to play along with the soundbar, as would other speakers. (Eg I can play TV audio from my soundbar, AND from my kitchen speakers, if I want)

In my household, as I suspect in many others with a member with hearing difficulties, it would move the Ace from a 'nice product but expensive' to a MUST HAVE!

Please make it so, Sonos. You're rightly known for your innovations - time to make it work for this very large section of the disabled community.

As stated here by @Marco B. from Sonos: 

The Sonos Ace connects to the soundbar in the same way as a surround speaker using 5Ghz WiFi. This won't work with other Sonos speakers than a soundbar.