What HT processor HDMI 2.1, and does that matter?

I'm currently using a Marantz AV7702 and when I got a PS5, which I use to stream netflix, amazon, etc., and I'll also get some 4k discs for a select few movies I really love, I had that issue with the video cutting out you may have heard about. I had to use the HDMI cable the PS5 came with, which is HDMI 2.1 certified, and the problem went away, even though neither the Marantz nor my TV has HDMI 2.1 inputs. I've been lusting after an Anthem AVM60 for a while b/c I think that will be better HT sound than the Marantz, but it also doesn't have HDMI 2.1, and neither does the current AVM70 as far as I know. Does this matter? Are there processors out there that sound good that do have HDMI 2.1? Alternatively, I was thinking of getting a TV that does have HDMI 2.1, putting the sources directly into it, and using the ARC (audio return channel) into the HT processor, but I wonder, does that significantly reduce the sound quality? I am skeptical of a TV's ARC in terms of audio but I have no experience with it. Has anyone experimented with setting it up that way and how does it sound? Thanks. 
The latest Anthem processors and receivers have HDMI 2.1


My experience with previous gen. Anthem, Audio Return Channel and LG has been really good. I pretty much do all my Netflix/Amazon streaming via the LG TV and have not had any audio problems at all.

In the past, with my Oppo and Samsung my ARC was spotty.  It would work once connected, but sometimes I'd have to power cycle one or the other to get it to connect. 

Thank you for the info. Seems like the ARC could be a reasonable option. The new Anthem AVM70 is out of my price range. Are there other HT processors out there that have HDMI 2.1 that I could get for under 2k or so (new or used)?
Honestly, the only thing that I see of any value for HDMI 2.1 is the Dynamic HDR.  The Atmos over ARC might be useful for some people, but there isn't any content that supports HDMI 2.1 (which is basically 8k video).  My opinion is that it's so early in this evolution that you really want to wait.

That being said, there is no physical difference between HDMI 2.1, HDMI 2.0, HDMI 1.4 cables.  The only real difference is that the older cables might be missing a connection for pin 14 (ethernet/ARC).

Even HDMI 2.0 / 2.1 certification really doesn't mean the cable is great.  I have seen really old cables such as Wire World Starlight 5-2 which blow away new cables that are HDMI 2.0 certified. lol.
That's interesting. You know much more about this than me. I'm curious, if the cables aren't actually different from 2.0 to 2.1, how come the picture keeps going out from the PS5 unless I'm using a 2.1 cable? I've read online that this happens frequently and the problem goes away with a 2.1 cable, as it did for me. I'm assuming the 2.1 cable that came with the PS5 is not a great HDMI cable in terms of audio and video quality but maybe I'm wrong. 
The certifications only say that the cable will support a certain level of data bandwidth.  This generally means that better wire is used or thicker gauge wire in some cases (or better design and better shielding for example).  However, it's a funny thing.  Some of the current Wire World cables (such as Ultraviolet 7) are exactly the same as the old 5-2 cables.  Your other HDMI cable may not be as good.
Also, with high bandwidth 4K, some cables can be picky and not all cables will work.
What HDMI cable would you recommend? Also, to maximize audio and video quality, do you recommend plugging sources into the HT processor and then running another HDMI cable to the tv, or running sources directly into the TV and using the ARC to the HT processor? Thanks again.
ARC is never as good as direct source.  Usually I connect sources directly to the HT Processor.  Then use the HDMI output on the processor to connect to the TV.

The HDMI cable recommendation is based on budget. The older Wire World Starlight 5-2 are a good cable, but they are getting rare and harder to find (probably because I'm always recommending them).  You can find the used on ebay or usaaudiomart sometimes.  I do have a couple of 1M and 2M cables.

If you are willing to get a really expensive cable, the Nordost Heimdall 2 is awsome, but $800 retail. 

Always get 2 meter minimum even if you don't need it.  The 1 meter cables do not perform as well because of digital signal reflections.

For real budget, the cryo-treated Neotech NEHH-4200 from Audio Sensibiliy is typically less than $100 for a 2 meter.
Thank you as always. $100 is about as much as I would want to pay for a cable that is connecting a PS5 or a Fios box to my HT processor. I will be sure to get a 1.5 meter or 2 meter cable instead of a 1 meter. I might try that Neotech cable and just see if it works, but if I did want a cable that was certified HDMI 2.1, do you have any recommendations? 
HDMI 2.1 is so new that there aren't good testing methods for this.  In reality, it is supposed to mean that the cable will support up to 42.6 Gbit per second data bandwidth.  Many manufacturers will "say" that it's HDMI 2.1 certified, but who can tell?

The best I can give you are a couple of cables that are actually tested and certified for HDMI 2.0.  This means that the cable has been tested to support up to 18 GBit per second, which is enough for full bandwidth 4K video.  If you google for "DPL Labs" you will get the company and you can drill down into their site to get the list of certified cables.

Out of that entire list, the only two I would recommend that come close to your budget is a USED Wire World Ultraviolet 7 HDMI or a USED Nordost Blue Heaven HDMI.  It's hard to say which one of these would be better.  The Nordost uses better copper.  However, the Wire World Ultraviolet has bigger 24awg conductors so there will be more "oomph" in the audio and better color saturation, but it could have a noiser digital signal which can come across with video noise or bright audio.

If you look closely, that cro-treated Neotech is almost exactly the same as the Nordost Blue Heaven.  It's just that the Neotech has never been tested for "certification" on the newer hdmi standards.  I bet that these two cables would test almost equal to eachother!