Video quality degradation vs Cable and antenna

General Discussion
#1

I’m getting less-than-great video quality through my OTA setup as compared with Spectrum cable TV or direct-connected antenna. Rather than go through 1000 permutations of setup variables, I’m hoping someone can give me advice as to where my bottleneck might be. Football, especially suffers from soft images and jumpy motion. My setup is as follows:

TV: Samsung Q70R QLED 4K 82”

Tablo Quad

ROKU Premier set to resolution Auto Detect, connected directly to TV HDMI input (I’m using ROKU’s Tablo app rather than native Samsung app because of better functionality)

Router: Spectrum supplied, which worked fine with cable TV content

Antenna: ChannelMaster Smartenna+, which works fine when connected directly to the TV.

Local TV OTA channels for sports: CBS @ 1080i, ABC @ 720p, FOX @ 720p

#2

What is the recording quality set to on your Tablo? See link below.

All the network connected DVRs do the following which reduces the video quality.

“Your Tablo hardware OTA DVR takes the raw ATSC TV signal coming in from your Over-the-Air antenna and uses a process called ‘transcoding’ to slice it into tiny digital pieces. Transcoding video makes it easier to stream to multiple devices over your home network, and over the internet.”

https://www.tablotv.com/blog/tablo-dvr-live-tv-recording-quality-settings/

You likely want the new HDMI connected DVR, which does NOT transcode / encode the video.

#3

Kind of the same and your previous posting… it’s not raw OTA signal

From: https://www.tablotv.com/blog/tablo-dvr-live-tv-recording-quality-settings/ -

Your Tablo hardware OTA DVR takes the raw ATSC TV signal coming in from your Over-the-Air antenna and uses a process called ‘transcoding’ to slice it into tiny digital pieces. Transcoding video makes it easier to stream to multiple devices over your home network, and over the internet. (Think of it like turning ice cubes into slush to make it easy to pour.)

#4

@chuck, You may have tried this, but one thing we did to smooth out the Tablo on a Samsung QLED was to turn off Auto Motion Plus. (I think that’s what it was called off the top of my head). This software based motion smoothing seemed to conflict with the Tablo stream in our house. Perhaps give that a try if you haven’t?

#5

I will try that. I did reduce the quality settings to 720p, which seems to have helped with dropouts, but the sharpness isn’t as good as with cable. Next I’m going to get an outdoor antenna, since in Melbourne, FL we’re quite a distance from Orlando where all the stations are. This should also help with the dropouts at least.

#6

Given the description of your problem, I’d be looking at your in home network as your possible bottleneck. Your two ways that work well don’t rely on a decent network, the Tablo would. As I see it:

Direct antenna: Antenna -> TV
Cable: Cable -> Cable Box -> TV (Note: I’m not familar with Spectrum, so might be wrong, but generally, most cable provided TV, even if the cable company also provides internet doesn’t use the internet to get the TV signal to the TV, it rides directly on the cable.)
Tablo: Antenna -> Tablo -> Network -> Router -> Network -> Roku -> TV

Is the Tablo directly wired to the router, or is connected over Wi-Fi? What obstructions exist between the Tablo and the router, and the Roku and the router? One way to test this is to record something to the Tablo, then use one the third party apps to download it to your computer and try watching it there. If you don’t see any skipping or jumping, then the tablo’s receiving the signal fine, and it’s interference between the tablo and the roku that you need to look into.

#7

This has little to no impact on your analogy, for clarification. When you “download” you’re actually streaming and capturing or converting it with ffmpeg - exporting recordings. Pretty much the only way to get something from your tablo is via HTTP steaming. (although not strictly accurate, mostly).
I only point this out, since you want to compare streaming vs not steaming but it was streamed.

#8

Correct. But in the absence of a way to watch the recording on the tablo directly, it’s the best option.

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#9

I’m using cat5e between the Tablo and the router. I’m getting occasional dropouts, too, and I assume those would be either because of poor antenna reception or router capability. Lots of things to try - shutting down everything else using the router, an outdoor antenna, another router. I’m adding so much new hardware, I wonder if dropping cable TV is worth the expense and effort but I’ll keep trying for a while. Thanks for the help, all of you.

#10

Before you worry about the router (which has almost nothing to do with OTA recording) you might want to use an inexpensive gigabit switch to connect the ethernet devices rather than using the built-in switch in your router. Inexpensive consumer routers are notorious for having poorly performing internal switches. You can get a decent switch (TrendNet, TP-Link, Netgear) for $20.

On the other hand, if it’s the Wifi performance of your router that’s the issue, a better router or adding a better WAP (Wifi Access Point) is the solution.

#11

Ah, ok. Could still be an issue between router and roku if the signal’s not great, but you’d probably notice the same issues in any other streaming you’re doing there (Netflix, Disney+, Roku Channel, etc…) Since you didn’t mention those, hard to say.

Another thing to check is what’s between the antenna and the tablo? I know you said it’s fine when connected directly to the tv, but any splitters etc between the two could also affect the signal. In our case, which was different than yours, when I hooked the TV up directly to the wall outlet, I couldn’t get the local NBC network. But with the Tablo sitting in the basement, connected directly to the feed from the antenna, bypassing the splitter that used to run to the wall plate mentioned, the signal on that channel is full strength. Still, based on your earlier comments, might not be an issue, but I always prefer to try to troubleshoot with removing things first and eliminating as much as possible before throwing money into new hardware.

#12

Good point about the router. No, there is no problem with Netflix or Prime, so the router is probably OK. I’m still leaning toward the antenna. I’m using an amplified indoor one with stations all about 38-40 miles away, so I guess I’m not doing too badly.

#13

I removed those 2 words from my environment, and can’t remember the last time I had a problem.

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#14

It’s true that you’re better off not using an amplifier at the antenna (and it MUST be at the antenna, not at the receiver) is because the amplifier itself generates noise. But if the signal isn’t strong enough, you have no choice except, maybe to get an antenna with higher gain. Today’s good antenna amplifiers (you get what you pay for) typically have a noise figure (NF) of less than 1 dB, meaning that the added noise is less than 25% greater than the input noise, but it’s still added noise. If you’re overdriving the receiver you can always add attenuator pads at the input.

#15

There is a distinction between an amp and a pre-amp, located an an antenna, as well as a distribution amp -

#16

I say tomahto, you say tomato. A pre-amp IS an amp. Take it from an engineer that worked with a 35 dB amplifier with a 0.8 dB noise figure at 5.6 Ghz as the first stage of a very powerful (sensitive) radar system prior to the actual receiver. We called it a low-noise amplifier.

#17

I can appreciate your advanced perspectives view, signal getting a boots - an amp. :+1:t2: :+1:t2:
Here in the consumer arena, we have to deal with marketing misnomers. Often struggle to have a, perhaps technical, yet not advanced to engineering level, understanding.
Of course knowledge is power - overload causes confusion

:thinking: ok <rhetorical>would I ever want a high-noise amplifier</rhetorical> :loud_sound:

#18

Sometimes when I speak to certain people, yes. :wink:

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#19

Roger that, djk. I ended up (A) disconnecting the antenna, and (B) turning off the router. With option (B) I got a pop-up message on the screen saying, “Could not connect to ROKU”. I didn’t get this with the live TV dropouts or when I disconnected the antenna, which tells me that the problem is the antenna signal. Sometimes you just gotta put your brain in gear and think things through… Anyway, I appreciate your help. I did fail to mention above, also, that any source of attenuation between the antenna and the receiver, like the cable itself, is a source of noise - the reason to use an amplifier at the antenna position so you aren’t amplifying the cable-generated noise as well as the signal. I know you’re aware of this, but someone reading this thread might not be.

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