4K requires an ultra HD 4K Blu-ray player or Netflix 4K subscription.
only limited content is available in 4K
i don’t believe satellite (directTV) is anywhere close to 4K
the best 4K TV and possibly the best TVs ever created so far (for non-gaming applications like movies) is the latest line of OLED TVs from LG
the latest DSP receivers are 4K compatible - the introduction of 4K receivers has been a bit of mess though with copy protection built in to the very latest HDMI standard....and only a few receivers supporting it. The trick with older receivers is to use one HDMI out from the blu-ray 4K player to the TV and the other HDMI out purely for audio to the receiver....
