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Comparing the DVRs?
zonker asks: "We are
getting hooked up with Dish
Network Satellite TV this weekend and opted to go with one of
their PVR
(personal video recorder) plans. I started wondering if anyone has
done any technical reviews or comparisons of the video quality (not
just features) of the various digital video recorders out there (TiVo, DishPVR,
ReplayTV, etc.). I am curious
mostly about recorded video quality compared to the source video.
All of them make claims to have various recording 'speeds' like
VCR's. VCR's analog output is predictable (fuzzy recording with bits
of static here and there, worse when signal quality is bad).
However digital recorders have varying levels of pixelization. I was
curious which ones fared the best and if anyone has comments on
either systems?"
Personally, what sold me on Tivo when I got it a year and a half ago was the great community at the AVS Tivo Forum. More info than you could ever want and a very supportive bunch for all kinds of questions. The Tivo FAQ is a good place to get answers to the basic questions first, though.
Although I'm a big fan of TiVo, in your case I'd reccommend a DishPVR if all you're concerned about is picture quality, unless you can get DirectTV in which case I'd reccommend a DirecTiVo.
DishPVR, DirectTiVo and UTV all store the satellite bitstream directly, so there is no quality setting, since there is no further compression.
1) You can select to record programs by searching by name, but it only searched within a limited horizon of programming (the week or so for which it has the guide). If not found, it can be recorded. For example, you couldn't ask it to record "Mission to Mars" whenever it comes on next.
Sure you can. Make a Title Wishlist for MISSION MARS and set it to auto-record. Done. That is the point of Wishlists, to record matching type things. Wishlists are in the 2.0 and up software, so if you just bought the Standalone unit, it'll only have 1.3 on there. It'll upgrade after it dials in a few times.
2) You can't ask it to record programs matching criteria like a particular actor, or keyword in title etc.
Again, use Wishlists. The possible wishlists are: Actor, Director, Keyword, Title (keyword but only in the title), and Genre.
3) Once a program has been selected for recording, you can't change the record quality without cancelling it, finding it again via search, channel guide or whatever, and re-selecting to record it.
Huh? Go to the ToDo List, find the show you want to change, hit select, then go to the "options" screen on that show. Change all the settings for that recording you like, including the quality.
4) It takes 2-4 hours to process and index the program guide after making a call to TiVo! (what on earth is it doing?)
Indexing the new data into it's database. However, this does tell me you have 1.3 software and not 2.0. The newer 2.0 software indexes in the background.
5) There are a few subtle bugs in the menu display software that sometimes cause display artifacts (rarely though).
Mostly fixed in 2.0 and up (2.5 is out now).
6) If you have a partial recording of something that you are also currently recording, it doesn't distinguish between the two - so you can delete the partial until the current recording it complete
Huh? I fail to understand this one, but all recordings are treated separately. If you record something and then it doesn't finish so you record it again later, those are separate and treated separately.
7) Sometimes the GUI is slow to respond (I assume the CPU is busy - just evert so slightly underpowered to do everything it needs. Although the record/playback seems to get highest priority - I've noticed no artifacts there)
Yes, it it a tad slow to respond at times. This was improved, but not fixed, in 2.0 and up.
In short, wait until you download the new software before passing judgement. The new software is tremendous compared to 1.3. It'll download 2.5 for you in under a week or two of first setting it up.
- Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
The three big ones for Dish based setups (DirecTivo's, UltimateTV's, and DishPVR's) all record the actual digital stream coming from the satellite. No encoding is done in the unit, so what you see on the feed is what you get on the recording. This doesn't mean there's no artifacts, it means that the artifacts will be the same as if you were watching it "live".
The other two major ones (Tivo standalone units, ReplayTV) are mostly comparable in picture quality.
Tivo has 4 picture quality settings, that range the spectrum pretty well, with "Best" being very close to live, and "Basic" being about VCR quality, but slightly sharper. Replay has 3 quality settings, I believe, and they are mostly the same as Tivo, picture wise.
Audio wise, it seems as if the Replay lowers the bitrate on the audio as well as the video in the lower quality settings, but this may be untrue or a rumor. Tivo definitely uses the same audio quality regardless of the quality setting. It sounds pretty good and I've not noticed any weirdness on Tivo audio except for some loss on the rear channel on Dolby Pro-Logic signals from time to time. Neither unit can record Dolby Digital, while the Dish/DTV-based units can and have digital outputs as well.
- Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
They almost did. A while back, any Gateway system came with some DishNetworks coupons. Why? Well at the time, they were working togther to bring Dish service to the Destination systems. The deal fell through, a few cards were made by Adaptec, and not much came of it.
That card on Happauge looks interesting. My biggest hurdle was the Nagravision Dish uses, but aparently that card supports it now. If only the links wern't broken on that page...
Ok, there are two basic classes of PVR's out now...
Ones for Digital Satellite Systems (They record the bit stream directly from the satellite without an analog to digital encoding process), and those for other systems (They convert analog TV into a digital MPEG stream and store it on disk).
To understand satellite systems. Incoming signals are buffered off the hard drive. (Long discussion about MPEG multicasting not gone into here, but the hard drive allows a longer error buffer to catch out of sequence key frames). You can then watch that stream or another stream off the hard drive. This allows you to watch a recorded show and record at the same time. But you cannot watch live and record something else.
DISH SYSTEM
Two Basic Systems
Dishplayer/WebTV (7100 and 7200)
The software for these were created by a division of microsoft. (Based on a unix core!).
They basically record the bitstream to disk. They have a very nice UI compared to other dish recievers. They have a 7 day guide, and support searching. (The searching is not as deep or complete as TIVO's searching).
They also have games (DOOM, You don't know jack, and solitare).
They also can be used as webtv terminals (though the software for webtv is a generation behind standalone webtv boxes).
The devices are somewhat hackable. You can put much larger drives in than came stock.
The software is buggy. Much more buggy than UltimateTV which uses alot of the same code as Dishplayer.
Dish Network and Microsoft have never been able to get the software update process smooth between them.
DISH PVR 501.
This is a Dish Product that is based on OpenTV and the software is written in house.
It has no search function, and has been recently upgraded to support a 9 day guide.
There are NO additional monthly subscription fees with the box.
DISH PVR 721 Next generation box due out early next year. Number one feature is to record more than one channel at a time. And to watch something live, and record at the same time.
NO monthly subscription fees.
DIRECT TV
Two basic choices.
Ultimate TV By Microsoft. Similar to Dishplayer, but able to record two streams simultaneously. A LOT less buggy than Dishplayer.
10 a month fee to use PVR.
DirectTivo
Same UI as regular Tivo, but records bitstream directly, and recently upgraded to record two streams simultaneously.
10 a month fee to use PVR
NON Satellite
TIVO
Replay