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So I've picked up a sound bar that has Optical and HDMI arc inputs.
I can connect the sky box with the optical no problems, but the blu ray player I have only has RCA audio output.
Can I just use an RCA to HDMI cable or am I looking at something more complicated?
Or can I split the HDMI output from the blu ray player?
I connected my parents soundbar using the sony tv hdmi arc output to soundbar hdmi arc input, Your blu ray player will already be connected for vision/sound to your tv by hdmi
Unlikely.
First what is the RCA, digital audio or analogue?
TV doesn't have a HDMI arc or optical output - only RCA too.
Are you sure? That sounds unlikely.
You keep saying RCA - that could be different things. See @rone's question. Is it a red/white analogue pair or coaxial digital? Also, is that in our out on the TV?
Photos of both if you're not sure, please.
If your players RCA is a digital / SPDIF it can be converted to optical with a cheap box.
Plug everything into the TV with hdmi. Then the sound will go back to the sound bar using arc with a single hdmi cable back to the sound bar.
If your TV doesn't have ARC on the HDMI then you could give something like this a go
AMANKA HDMI Audio Splitter, 4K HDMI Audio Splitter Adapter for Home Theater Application,Optical SPDIF Toslink with 3.5mm Stereo Audio Converter Adapter Support for Blu-ray DVD Player Xbox One PS4 https://www.amazon.co.uk/dp/B07BPNLRS5/ref=cm_sw_r_cp_apa_i_cobfCbWY1TZ4X
RCA outputs from BR players are usually the standard ones, so composite video and LR analogue audio. Best not to use them if you can avoid it. One option is you can get optical Toslink splitters so that might be your best route in the absence of an ARC HDMI on your TV. You're unlikely to be wanting to use your Sky AND BR audio at the same time. However I suspect you'd need to turn off the source you're not listening too to ensure its not outputting, so a small amount of inconvenience there.
Sorry for the late reply - been busy.
Back of the TV has composite audio L/R.
The DVD player has a digital coax out for audio - picture below.
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Currently got it connected with a Bluetooth transmitter - not too bad but there is a slight delay.
So can I go from the Digital coax to either HDMI arc or optical?
You can with something like this. It's an active conversion since the optical side needs a laser to drive it, so you can't just get a cable which plugs directly into both connections. See here for various options.
...Now has someone hidden the preview button so I can check the links before posting?
No option on the tv to adjust audio delay? There is on our Samsung.