4K TV and AV Receiver Purchase

[SymS]

I plan to buy a 4K TV and and AV receiver, and I have a budget of 50,000 Baht.

The requirements are as follows:

• 4K TV – HDMI 2.0 for 2160p @ 60 Hz support, HDMI-CEC, and optionally MHL and 3D support.
• AV Receiver – HDMI and S/PDIF input. Display showing Codec. 4K pass-through. Codecs: Dolby Digital 5.1, Dolby Digital+ 5.1/7.1, TrueHD 5.1/7.1, DTS HD, and DTS MA

For my purpose I don't really care about the size of the TV, and/or power of the AV receiver.

But what I've found out is that prices in Thailand for AV equipment seem to be more expensive than in western countries.

I went to Sahapanich in Chiang Mai to check out what's available, and check websites like Lazada. I'd rather buy locally, because of warranty, but prices are much better online. At first I leaned towards:

• Onkyo TX-NR626 AV receiver - 18,900 THB on Lazada (http://www.lazada.co.th/onkyo-tx-nr-626-461312.html)
• LG 49UB830T (http://www.lg.com/th/tv/lg-49UB830T) which sells for about 36,000 Baht online.

However, this is still over budget (even before speakers),and although the seller told me UB830T would support HDMI 2.0, the product page only list HDMI 1.4 ports.

I'm wondering if there could be better options considering my budget and requirements. Thanks.

[IMHO]

Do you really need 3D? - especially in such a small screen - 3D makes the TV look almost half the size again, so not something I'd recommended for <65" at normal seating distance (and if your sitting close to the screen, 3D is just weird)

If you reconsider the 3D requirement, there are some good deals on the LG UB820T (non-3D) 4K sets ATM - the 42" can be had for 19.9K and the 49" for 27K. The UB830T series has passive 3D for an extra 10-12K Baht, but they're much harder to find. The UB850T series add WebOS onto the spec sheet, but come with a very big price jump..

I think that most people buying 4K now have already had a 1080P 3D set, and are well and truly over it now - and the availability/pricing of the 820T vs 830T's reflects that.

As for AVR's, it's pretty hard to beat the Onkyo's in the low-end, but I suppose you could also consider the Denon AVR-X1100, Yamaha RX-V477 and Marantz SR-5007 - all of these are available for around 22K Baht - but do note that they are all 4K pass-through only, without an upscaler like the Onkyo. That may or may not matter to you though, considering the TV will have it's own upscaler.

In the 8xxT series, LG do not clearly specify the HDMI version - they only say it supports 4K @ 60FPS. I know that they don't support 4:4:4 color space though, but I seriously doubt that's of much concern when you're buying a (relatively) low-end IPS panel anyway (I'd only be concerned about 4:4:4 if I was buying OLED)

[SymS]

Thanks! That's useful information.

Do you really need 3D? - especially in such a small screen - 3D makes the TV look almost half the size again, so not something I'd recommended for <65" at normal seating distance (and if your sitting close to the screen, 3D is just weird)

It's optional, for my purpose (reviews) I would just need to confirm it works, and I'd be pretty close from the screen (1 to 1.5m), but if it adds 10K just for this I'll skip I think.

LG-42UB820T would be OK, but what I'd really like is HDMI 2.0 since I need to check 2160p 60Hz output works.

On that LG page (Singapore?): http://www.lg.com/sg/tvs/lg-42UB820T there's an HDMI 2.0 port,

but on the Thai page: http://www.lg.com/th/tv/lg-42UB820T there's no HDMI 2.0.

The seller told me to go with UB830T for HDMI 2.0, but there's no such port listed either on the Thai website, only HDMI 1.4. Maybe I'll just need to bring a TV box and try onsite.

Someone told me Onkyo receviers are "notorious for dieing of thermal issues", so I'll also have a look at the AV receivers you listed too.

[IMHO]

Thanks! That's useful information.

Do you really need 3D? - especially in such a small screen - 3D makes the TV look almost half the size again, so not something I'd recommended for <65" at normal seating distance (and if your sitting close to the screen, 3D is just weird)

It's optional, for my purpose (reviews) I would just need to confirm it works, and I'd be pretty close from the screen (1 to 1.5m), but if it adds 10K just for this I'll skip I think.

LG-42UB820T would be OK, but what I'd really like is HDMI 2.0 since I need to check 2160p 60Hz output works.

On that LG page (Singapore?): http://www.lg.com/sg/tvs/lg-42UB820T there's an HDMI 2.0 port,

but on the Thai page: http://www.lg.com/th/tv/lg-42UB820T there's no HDMI 2.0.

The seller told me to go with UB830T for HDMI 2.0, but there's no such port listed either on the Thai website, only HDMI 1.4. Maybe I'll just need to bring a TV box and try onsite.

Someone told me Onkyo receviers are "notorious for dieing of thermal issues", so I'll also have a look at the AV receivers you listed too.

According to the owner's manual, the UB820T and UB830T's have the exact same HDMI connections and capabilities:

4K @ 50/60 Hz Support Format

Resolution Frame rate(Hz) Colour Depth/Chroma Sampling

3840 x 2160p 50.00 8 bit / YCbCr 4:2:0

4096 x 2160p 59.94

60.00

None of these actually require HDMI2.0...

[IMHO]

Actually, my last statement isn't true....

HDMI 1.4 can only do max. 30fps @ 2160P, so the short answer is, those LG's must be HDMI 2.0

Ref: http://www.hdmi.org/manufacturer/hdmi_1_4/hdmi_1_4_faq.aspx#21

[SymS]

Actually, my last statement isn't true....

HDMI 1.4 can only do max. 30fps @ 2160P, so the short answer is, those LG's must be HDMI 2.0

Ref: http://www.hdmi.org/manufacturer/hdmi_1_4/hdmi_1_4_faq.aspx#21

And I contacted LG Thailand on Facebook:

"LG Thailand Service Support says HDMI 2.0. Sorry about wrong information on LG Thailand website."

So that looks all good.

[IMHO]

Super. Just ordered the 49" for my bedroom

[SymS]

Super. Just ordered the 49" for my bedroom

Wow that was fast! Did you order online? I considering buying one online too, but I worry about warranty...

How would that work? Just bring the TV at the closest LG service center, and they'll cover the repair if if it under warranty?

[IMHO]

Super. Just ordered the 49" for my bedroom

Wow that was fast! Did you order online? I considering buying one online too, but I worry about warranty...

How would that work? Just bring the TV at the closest LG service center, and they'll cover the repair if if it under warranty?

Yep, ordered online from cdiscount for 27,030 delivered. Looks like they are out of stock now though: http://www.cdiscount.co.th/lg-ultra-hd-smart-led-tv-49-inch-49ub820t-19041

In my experience, there's no real advantage buying from bricks and mortar, as all warranty claims need to go to the manufacturers service centre anyway. I have never had a problem getting warranty service when buying from Thai vendors on or offline (well tested with the 2 Samsung TV's I own).

Looks like the 42" is sold out too: http://www.cdiscount.co.th/lg-ultra-hd-smart-led-tv-42-42ub820t-17293 which means that now costs 21.5K from Lazada (next best price).

[IMHO]

Just noticed that Cdiscount have the 42" back in stock now, 1 left, 19.9K Baht....

[chris2004]

I am thinking of getting a 4K receiver to go with my LG 4K TV. I thought however that you needed HDCP 2.2 and that the only receiver that offers that at the moment is the Onkyo 636 @ 25,000 baht.

[IMHO]

I am thinking of getting a 4K receiver to go with my LG 4K TV. I thought however that you needed HDCP 2.2 and that the only receiver that offers that at the moment is the Onkyo 636 @ 25,000 baht.

If the receiver is able to do true 4K pass-through (i.e. it acts just like a HDMI switcher), it doesn't need to support HDCP, in theory. But until 4K Bluray releases - which is the only way we'll see stable 4K video in TH for the near future - it's all a bit risky because none of it is truly tested.

The expectation is that 4K bluray will need HDCP 2.2 - but I haven't yet seen any official specs, so for now that's just speculation (based on Netflix needing it, from what I can read). Then there's chatter about from the chipset geeks saying that even AVR's being advertised as HDMI 2.0 and HDCP 2.2, don't support the full 18gpbs HDMI 2.0 bandwidth, so presumably can't support all the new enhancements HDMI 2.0 is capable of.

If you already have an AVR in the system, I'd say wait. You don't actually need a 4K AVR until we get proper 4K sources.

[SymS]

Just noticed that Cdiscount have the 42" back in stock now, 1 left, 19.9K Baht....

Thanks! Unfortunately, I missed it. But this morning Lazada sent a 10% discount coupon, so I bought it there for about the same price (19.6k).

I also bought the AV receiver yesterday, but locally since I could not find service center in Chiang Mai, so I would have to sent it to Bangkok in case something goes wrong. Model: Onkyo TX-NR636 for 25,000 Baht in Sahapanich with a 3-year warranty.

[chris2004]

SymS let me know what you think of the 636, i was thinking of getting one too. Thanks.

[IMHO]

Any word on whether the 636 is going to be firmware upgradable to support DTS:X when it releases in March?

[SymS]

SymS let me know what you think of the 636, i was thinking of getting one too. Thanks.

I'm still waiting for the speakers. It's my first AV receiver, and I'll only connect 4 speakers, so I'm not sure I'm the best one to give an opinion. But I'll try after I play with it. I'll actually write a getting started on my Blog.

There are plenty of user's feedbacks on Amazon or Newegg. The main complain is that the HDMI board may break after two years or so, which is why I would not have bought it without 3-year warranty (First I looked at TX-NR626 on Lazada: No warranty). Some people may also have problems with Bluetooth or Wi-Fi (Can't remember for sure, I've read too many things about different AV receivers recently .

[SymS]

Any word on whether the 636 is going to be firmware upgradable to support DTS:X when it releases in March?

I had never heard about DTS:X before, but it looks like it has been announced right at the end of December. So it's all very new.

I guess the answer is no. https://www.facebook.com/video.php?v=10153518369639689&reply_comment_id=10153535923779689&total_comments=1

[bkkjames]

What content is available for 4k?

[SymS]

What content is available for 4k?

YouTube and Netflix support 4K, but I guess it's not realistic with the bandwidth available, and for YouTube it relies on uploaders shooting 4K videos.

It can be useful if you have a 4K capable video camera, or smartphone (e.g. Nexus 6).

Going through photos on a 4K TV should also look better.

[IMHO]

What content is available for 4k?

YouTube and Netflix support 4K, but I guess it's not realistic with the bandwidth available, and for YouTube it relies on uploaders shooting 4K videos.

It can be useful if you have a 4K capable video camera, or smartphone (e.g. Nexus 6).

Going through photos on a 4K TV should also look better.

Youtube 4K only takes around 10mbps, and streams reasonably well in TH. The problem is it's highly compressed, and you soon tire of watching nature scenes and the couple of 4K movie trailers out there - which is all that's really available.

Netflix 4K requires around 15mbps, and on my (pretty solid) 20mbps connect is just not workable, at all. Even then, they only have two proper titles available (House of Cards and Breaking Bad). It's also noticeably compressed, but better PQ than YT.

Both of them look better than their 1080P (also compressed) streaming counterparts, but struggle to beat upscaled Blu-ray Picture Quality, IMHO. On top of that, Blu-ray absolutely annihilates all online streaming when it comes to sound quality... A DTS-HD MA lossless audio stream uses on average 15mbps on it's own (and up to 24.5mbps) - so we can all forget about getting good audio online for a long, long time...

4K Blu-rays are promised to be here by the end of this year though, and Panasonic showed a pre-production device @ the CES earlier this month - that's what's going to make all the difference...

Until then, the best way to take advantage of the extra pixels will be using the TV as a PC display, and upscaling high quality Blu-ray 1080P content.

[bkkjames]

Or wait until prices come down and some content is readily available. Lol

[IMHO]

Or wait until prices come down and some content is readily available. Lol

Absolutely!

However, prices are already dropping fast, so if you're in a position where you just need to buy a new TV, it's definitely worth at least looking at 4K options/prices. The other point is, once all manufacturers have cleared their 2014 stock / released their 2015 stock, what you'll find is that all the PQ tech will be going into 4K sets only - 1080P sets will become cheaper, and worse looking than they currently are, comparatively.

i.e. If you're shopping for mid-high end TV during this year, you'll be practically forced to buy a 4K screen, because they will be the only ones with the latest PQ wizadry - just like what happened to "HD" TV's once "Full HD" became mainstream. All the arguments about seating distance vs resolution will also become moot then too, because 4K will just look better, regardless of the extra pixels and whether or not you can see them

[chris2004]

IMHO that was my thinking, i wanted a 65 inch TV this year so why pay 70,000 for a 1080p when i can get a 4k for 82,000.

[Anthony5]

What content is available for 4k?

YouTube and Netflix support 4K, but I guess it's not realistic with the bandwidth available, and for YouTube it relies on uploaders shooting 4K videos.

It can be useful if you have a 4K capable video camera, or smartphone (e.g. Nexus 6).

Going through photos on a 4K TV should also look better.

Youtube 4K only takes around 10mbps, and streams reasonably well in TH. The problem is it's highly compressed, and you soon tire of watching nature scenes and the couple of 4K movie trailers out there - which is all that's really available.

Netflix 4K requires around 15mbps, and on my (pretty solid) 20mbps connect is just not workable, at all. Even then, they only have two proper titles available (House of Cards and Breaking Bad). It's also noticeably compressed, but better PQ than YT.

Both of them look better than their 1080P (also compressed) streaming counterparts, but struggle to beat upscaled Blu-ray Picture Quality, IMHO. On top of that, Blu-ray absolutely annihilates all online streaming when it comes to sound quality... A DTS-HD MA lossless audio stream uses on average 15mbps on it's own (and up to 24.5mbps) - so we can all forget about getting good audio online for a long, long time...

4K Blu-rays are promised to be here by the end of this year though, and Panasonic showed a pre-production device @ the CES earlier this month - that's what's going to make all the difference...

Until then, the best way to take advantage of the extra pixels will be using the TV as a PC display, and upscaling high quality Blu-ray 1080P content.

So buy the time that you're able to view the content available for your 4K tv in Thailand, 20K tv's will be all over the place

I have 1080P tv's at my place, and when I have a visitor he will say that's a good picture. On which I'll reply, yeah they are 4K, and the visitor will say yes you can see that.

I actually don't lie, because I mean they are 4K Baht worth now.

[IMHO]

What content is available for 4k?

YouTube and Netflix support 4K, but I guess it's not realistic with the bandwidth available, and for YouTube it relies on uploaders shooting 4K videos.

It can be useful if you have a 4K capable video camera, or smartphone (e.g. Nexus 6).

Going through photos on a 4K TV should also look better.

Youtube 4K only takes around 10mbps, and streams reasonably well in TH. The problem is it's highly compressed, and you soon tire of watching nature scenes and the couple of 4K movie trailers out there - which is all that's really available.

Netflix 4K requires around 15mbps, and on my (pretty solid) 20mbps connect is just not workable, at all. Even then, they only have two proper titles available (House of Cards and Breaking Bad). It's also noticeably compressed, but better PQ than YT.

Both of them look better than their 1080P (also compressed) streaming counterparts, but struggle to beat upscaled Blu-ray Picture Quality, IMHO. On top of that, Blu-ray absolutely annihilates all online streaming when it comes to sound quality... A DTS-HD MA lossless audio stream uses on average 15mbps on it's own (and up to 24.5mbps) - so we can all forget about getting good audio online for a long, long time...

4K Blu-rays are promised to be here by the end of this year though, and Panasonic showed a pre-production device @ the CES earlier this month - that's what's going to make all the difference...

Until then, the best way to take advantage of the extra pixels will be using the TV as a PC display, and upscaling high quality Blu-ray 1080P content.

So buy the time that you're able to view the content available for your 4K tv in Thailand, 20K tv's will be all over the place

I have 1080P tv's at my place, and when I have a visitor he will say that's a good picture. On which I'll reply, yeah they are 4K, and the visitor will say yes you can see that.

I actually don't lie, because I mean they are 4K Baht worth now.

hehehe

But think about the person currently looking for say, a 48-50" TV. Options are, spend around 13K Baht of the cheapest, no-name Chinese 1080P panel, 17- 20K Baht for a low-end name brand 1080P panel, 22-30K for a mid-range 1080P panel, and anywhere from 35K and up for a high-end 1080P panel (while you can still find one).

A mid-range 49" 4K IPS panel can now be had for 26K Baht, putting them in the exact same price range as it's respective 1080P counterparts - and forgetting the extra dots, it also has an IPS screen with local dimming - two things which improve PQ regardless of source - which it's same-price 1080P competition are unlikely to have.

1080P is already being relegated to the ranks of low-end-only picture quality tech.

I'm not saying it's the time to buy, no way - prices will drop, but if you're in a position where you need to buy, as prices drop your pain will be a little less, if at least you bought something with a little longer shelf life

If you're only interested in low-end TV's, you're probably reading the wrong thread

[SymS]

FYR. I've taken a few pictures for 42UB820T, and written a review: http://www.cnx-software.com/2015/01/24/lg-42ub820t-4k-uhd-tv-review/

[IMHO]

FYR. I've taken a few pictures for 42UB820T, and written a review: http://www.cnx-software.com/2015/01/24/lg-42ub820t-4k-uhd-tv-review/

Nice review

Just a couple of things to add:

the UB850T series has an onboard H.265/HEVC decoder capable of 60FPS - the UB820T and UB830T's HEVC decoder can only manage 30FPS. Not that it's a big issue really - we're a long, long way away from 4K streaming @ 60FPS, and the only real use-cases for 60FPS 4K are going to be live sports and gaming - the former which we won't see for such a long time it's not even worth thinking about, the latter which doesn't need HEVC...

I've seen that seating distance guide you published before, and I call BS on it. According to that, on my 65" Panasonic VT plasma, I can't see the difference between 720P and 1080P content at my normal seating distance of 4.5M (14.75 foot), which is complete and utter rubbish - I can clearly tell the difference between 1080i and 1080P at the sofa.. It also suggests that at 5.5M or so, I can't tell the difference between SD and anything with a HD label, which is just outright laughable - that difference is noticeable even from 10M (right at the back of the room).

[IMHO]

I've seen that seating distance guide you published before, and I call BS on it. According to that, on my 65" Panasonic VT plasma, I can't see the difference between 720P and 1080P content at my normal seating distance of 4.5M (14.75 foot), which is complete and utter rubbish - I can clearly tell the difference between 1080i and 1080P at the sofa.. It also suggests that at 5.5M or so, I can't tell the difference between SD and anything with a HD label, which is just outright laughable - that difference is noticeable even from 10M (right at the back of the room).

Further to this, I just did some testing on 1080P vs 4K on my set, using Big Buck Bunny files I found from your blog (thanks).

Setup is:

2014 Macbook Pro Retina 15"

LG 49UB820T

Seating distance: 3.2M (10.5 feet)

1080P video output at 1080P by the macbook, then upscaled by the TV looks about 85-90% as good as the actual 4K stream. Looking at the actual 4K version, even at 3,2M distance the picture is noticeably crisper - but admittedly only on selected scenes - some of them are so soft in rendering there's just no visible difference. The best scene I found was when the squirrel(?) was flying, and looking down at the bunny - that really clearly showed the difference between the formats.

1080P upscaled by VLC and output at 2160P by the macbook pro, looks at best around 65-70% as good as raw 4K. It's very noticeably softer all round, and clearly not as good as letting the TV do the upscaling, no matter what the scene.

OK, not very scientific testing, but my eyes don't lie - it's not a case of straining to see the difference, it's just clear. That seating distance chart, which almost seems to be taken as gospel online, is just plain wrong IMHO - according to it, at 10.5 feet with a 48.5" screen, I can't see any difference between 720P and any higher res - it's just plain hogwash.

Note: I do not profess to have fantastic eyesight or anything like that (I do have a good pair of ears though ) - I'm now in my early 40's and already finding myself holding my cereal box a little further away in order to read the fine print

@OP: I'm curious if your findings are similar?

Oh yeah, one other thing about these UB820T's - the wall mount holes are almost directly in line with the power cord socket on the set, so you really need to be careful about the wall mounting kit used - generic style kits which work from say 30" - 60" will very likely block the power socket! I had to buy another, smaller kit, just for this TV

[SymS]

I've seen that seating distance guide you published before, and I call BS on it. According to that, on my 65" Panasonic VT plasma, I can't see the difference between 720P and 1080P content at my normal seating distance of 4.5M (14.75 foot), which is complete and utter rubbish - I can clearly tell the difference between 1080i and 1080P at the sofa.. It also suggests that at 5.5M or so, I can't tell the difference between SD and anything with a HD label, which is just outright laughable - that difference is noticeable even from 10M (right at the back of the room).

Further to this, I just did some testing on 1080P vs 4K on my set, using Big Buck Bunny files I found from your blog (thanks).

Setup is:

2014 Macbook Pro Retina 15"

LG 49UB820T

Seating distance: 3.2M (10.5 feet)

1080P video output at 1080P by the macbook, then upscaled by the TV looks about 85-90% as good as the actual 4K stream. Looking at the actual 4K version, even at 3,2M distance the picture is noticeably crisper - but admittedly only on selected scenes - some of them are so soft in rendering there's just no visible difference. The best scene I found was when the squirrel(?) was flying, and looking down at the bunny - that really clearly showed the difference between the formats.

1080P upscaled by VLC and output at 2160P by the macbook pro, looks at best around 65-70% as good as raw 4K. It's very noticeably softer all round, and clearly not as good as letting the TV do the upscaling, no matter what the scene.

OK, not very scientific testing, but my eyes don't lie - it's not a case of straining to see the difference, it's just clear. That seating distance chart, which almost seems to be taken as gospel online, is just plain wrong IMHO - according to it, at 10.5 feet with a 48.5" screen, I can't see any difference between 720P and any higher res - it's just plain hogwash.

Note: I do not profess to have fantastic eyesight or anything like that (I do have a good pair of ears though ) - I'm now in my early 40's and already finding myself holding my cereal box a little further away in order to read the fine print

@OP: I'm curious if your findings are similar?

Oh yeah, one other thing about these UB820T's - the wall mount holes are almost directly in line with the power cord socket on the set, so you really need to be careful about the wall mounting kit used - generic style kits which work from say 30" - 60" will very likely block the power socket! I had to buy another, smaller kit, just for this TV

Thanks for testing. I have not tried testing distance yet. The conversion method or device used to scale from 2160p to 1080p may affect the video quality, maybe I'll try to convert the 4K video to 1080p with high quality settings, instead of just using 1080p and 2160p videos. I'll also try to find an alternative distance / size chart.

Have you tried to use the TV as a computer monitor when connected to your Macbook Pro Retina 15"? Some people have asked me.

[IMHO]

I've seen that seating distance guide you published before, and I call BS on it. According to that, on my 65" Panasonic VT plasma, I can't see the difference between 720P and 1080P content at my normal seating distance of 4.5M (14.75 foot), which is complete and utter rubbish - I can clearly tell the difference between 1080i and 1080P at the sofa.. It also suggests that at 5.5M or so, I can't tell the difference between SD and anything with a HD label, which is just outright laughable - that difference is noticeable even from 10M (right at the back of the room).

Further to this, I just did some testing on 1080P vs 4K on my set, using Big Buck Bunny files I found from your blog (thanks).

Setup is:

2014 Macbook Pro Retina 15"

LG 49UB820T

Seating distance: 3.2M (10.5 feet)

1080P video output at 1080P by the macbook, then upscaled by the TV looks about 85-90% as good as the actual 4K stream. Looking at the actual 4K version, even at 3,2M distance the picture is noticeably crisper - but admittedly only on selected scenes - some of them are so soft in rendering there's just no visible difference. The best scene I found was when the squirrel(?) was flying, and looking down at the bunny - that really clearly showed the difference between the formats.

1080P upscaled by VLC and output at 2160P by the macbook pro, looks at best around 65-70% as good as raw 4K. It's very noticeably softer all round, and clearly not as good as letting the TV do the upscaling, no matter what the scene.

OK, not very scientific testing, but my eyes don't lie - it's not a case of straining to see the difference, it's just clear. That seating distance chart, which almost seems to be taken as gospel online, is just plain wrong IMHO - according to it, at 10.5 feet with a 48.5" screen, I can't see any difference between 720P and any higher res - it's just plain hogwash.

Note: I do not profess to have fantastic eyesight or anything like that (I do have a good pair of ears though ) - I'm now in my early 40's and already finding myself holding my cereal box a little further away in order to read the fine print

@OP: I'm curious if your findings are similar?

Oh yeah, one other thing about these UB820T's - the wall mount holes are almost directly in line with the power cord socket on the set, so you really need to be careful about the wall mounting kit used - generic style kits which work from say 30" - 60" will very likely block the power socket! I had to buy another, smaller kit, just for this TV

Thanks for testing. I have not tried testing distance yet. The conversion method or device used to scale from 2160p to 1080p may affect the video quality, maybe I'll try to convert the 4K video to 1080p with high quality settings, instead of just using 1080p and 2160p videos. I'll also try to find an alternative distance / size chart.

Have you tried to use the TV as a computer monitor when connected to your Macbook Pro Retina 15"? Some people have asked me.

Let's say you were to create a super-high bitrate 1080P video from the 4K source, is that really indicative of real-world 1080P vs 4K content though?

On that front, streaming 4K from Netflix (yes, it's very painful watching something in chunks of a few seconds each as it buffers) only looks very marginally better (like single digit %'s), and only at some times, to 1080P blu-rays upscaled by the TV - I haven't yet however had the chance to A/B test the exact same content - so that's just a general observation.

The Big Buck Bunny files are the best real test I've found yet - the 1080P version meets my blu-ray level PQ expectations, and the 4K version properly exceeds them, on some scenes. The shallow depth of field used on many scenes, and heavy antialiasing on details like grass, means that not all scenes are candidates for A/B comparisons though - that's nothing to do with the playback tech though, just the production.

As for using it as a monitor:

1) When sitting very close to the screen, in a position where you're "looking up" to see the top few pixels, you get an odd shadow effect:

When looking down at the screen (or when sitting far away from it), this effect is no more:

It appears as if the backlighting plane is about 2-3mm behind the actual LCD pane - and as you move your head there's a 3D 'parallax' effect going on at the edges. Note I have taken these photos to show the effect at maximum, and in OSX I really only notice it on the light gray menu bar at the top of the screen.

2) On my 2014 MBPr, the max. refresh rate is 30Hz/FPS, which is OK for desktop/web/video, but useless for games. It's not such a big deal, because the GeForce graphics card in it can't handle anything heavier than Angry Birds at these resolutions anyway. Nothing to do with the TV though.

3) I get noticeable mouse lag at 4K res. Not enough to stop you working I guess - it's a few ms at worst - but it's annoying. Again, nothing to do with the TV. Edit: I only get this when the MBPr is outputting both 4K over HDMI *and* 2880x1800 for it's own internal screen at the same time - shut off the internal screen and it goes away.

4) The desktop does become massive.... really massive. Sure the numbers tell you that anyway, but it still kind of hits you. Here's a photo using the "standard" web browser window size I use on my MBPr. Everything is super-readable on the TV, even at 1:1 without any display scaling though: