or Connect
AVS › AVS Forum › HDTV › HDTV Recorders › D-VHS vs DVR for recording HD?
New Posts  All Forums:Forum Nav:

D-VHS vs DVR for recording HD?

post #1 of 117
Thread Starter 
Most DVRs have set limits for the content it can store. i.e 40 hr HD or 200 hr Std etc.. So I am guessing they use constant bitrate for each second recorded whether the programs bitrate exceeds it or not.

From Tivo 1 TB external HDD spec

1TB= 140 Hr HD content = 16mbps

D-VHS recorders can record upto 28mbps(I am pretty sure none of the cable & Sat provider support such high bitrate but may exceed 16mbps time to time?)

So from this, can we assume D-VHS recorders can record HD content better than DVRs?

I know D-VHS is a dead technology but still exist in used market. For those who have Vhs collections(still, these players are among the best for Vhs and s-vhs playback/record.

update: I just remembered most cable & sat providers switched to mpeg-4 which is far more efficient than D-VHS' mpeg-2 encoding. So 16mbps in mpeg-4 should result better picture than 28mbps in mpeg-2.
post #2 of 117
I regularly use DVHS to archive 1080i broadcasts. The recordings are bit for bit recordings of the 1080i stream coming out of the cablebox. The highbit rate means that there is zero loss on my recordings. They are look exactly like the original stream.

DVHS is great for archiving. A DVR, if you cannot get the show off of the box in a lossless state, not so much. I use older Moto 6412 units to record and I would not trust any important recording to stay on them for too long.

I own six DVHS units so I am a big fan of the format.

By the way, I live in northwest Ohio but I lived in Westport until I was 21 years old. I grew up in Fall River. I miss the ocean

Tom
post #3 of 117
Quote:
Originally Posted by uderman View Post

Most DVRs have set limits for the content it can store. i.e 40 hr HD or 200 hr Std etc.. So I am guessing they use constant bitrate for each second recorded whether the programs bitrate exceeds it or not.

From Tivo 1 TB external HDD spec

1TB= 140 Hr HD content = 16mbps

The quoted time on a TiVo is, if you read the fine print, noted to be subject to the specifics of the content. However, 16 Mbps is a fair average bitrate overall for OTA and digital cable HD programs, so it's not much of an overstatement of capacity.

Quote:
Originally Posted by uderman View Post

D-VHS recorders can record upto 28mbps(I am pretty sure none of the cable & Sat provider support such high bitrate but may exceed 16mbps time to time?)

At least with OTA and digital cable, the highest bitrate you'll get is ~19.4 Mbps. A single QAM channel on cable can transport about 38.8 Mbps, but those are normally at least two streams (content channels) per QAM channel, sometimes 3 streams. Dunno about satellite, but it's probably similar.

Quote:
Originally Posted by uderman View Post

So from this, can we assume D-VHS recorders can record HD content better than DVRs?

Wrong. Modern DVRs capture the exact bitstream from whatever the programming source is.

Quote:
Originally Posted by uderman View Post

update: I just remembered most cable & sat providers switched to mpeg-4 which is far more efficient than D-VHS' mpeg-2 encoding. So 16mbps in mpeg-4 should result better picture than 28mbps in mpeg-2.

And cable providers are moving (slowly) to switch to MPEG-4 AVC for that reason (and for 3D, but who cares about that, right?).
post #4 of 117
You can copy recordings off a TiVo. Only advantage a D-VHS deck would have is archiving copy once material.
post #5 of 117
Quote:
Originally Posted by Star56 View Post

I regularly use DVHS to archive 1080i broadcasts. The recordings are bit for bit recordings of the 1080i stream coming out of the cablebox. The highbit rate means that there is zero loss on my recordings. They are look exactly like the original stream.

DVHS is great for archiving. A DVR, if you cannot get the show off of the box in a lossless state, not so much. I use older Moto 6412 units to record and I would not trust any important recording to stay on them for too long.

I own six DVHS units so I am a big fan of the format.

By the way, I live in northwest Ohio but I lived in Westport until I was 21 years old. I grew up in Fall River. I miss the ocean

Tom

Ha-I have you beat as I have, lets see 14=4 Mits 2000, 4 JVC 30K, 4 JVC 40K, and 2 JVC 100U's. All bought new off mainly fleabay within the last year.
DVHS decks are dirt cheap compared to the $1500 insanity they were marketed for a few years ago. I am also building my D-Theater collection.

I also have 3 Tivo S3's and a Motorola DVR.
post #6 of 117
I got a 5u in '04 ... which was very much at the tail end of the DTheater era. But it was HiDef at a time when HD DVD and BD were all just talk. Bought 6 movies (including Alien and Bourne Identity - still watch Alien on it) and was as happy as a clam. I've since purchase a second deck (5u) just as a backup. It never gets used ... in fact I should probably fire it up once in a while to keep things fresh.

But anyway, at this point I used it primarily as an archive tool to move stuff off my Comcast Moto DVR. I wouldn't think of having a home theater without one.
post #7 of 117
Quote:
Originally Posted by Star56 View Post

I regularly use DVHS to archive 1080i broadcasts. The recordings are bit for bit recordings of the 1080i stream coming out of the cablebox. The highbit rate means that there is zero loss on my recordings. They are look exactly like the original stream.

DVHS is great for archiving. A DVR, if you cannot get the show off of the box in a lossless state, not so much. I use older Moto 6412 units to record and I would not trust any important recording to stay on them for too long.

I own six DVHS units so I am a big fan of the format.

By the way, I live in northwest Ohio but I lived in Westport until I was 21 years old. I grew up in Fall River. I miss the ocean

Tom

Quote:
Originally Posted by qz3fwd View Post

Ha-I have you beat as I have, lets see 14=4 Mits 2000, 4 JVC 30K, 4 JVC 40K, and 2 JVC 100U's. All bought new off mainly fleabay within the last year.
DVHS decks are dirt cheap compared to the $1500 insanity they were marketed for a few years ago. I am also building my D-Theater collection.

I also have 3 Tivo S3's and a Motorola DVR.


I knew Star56 had a few or more machines. But 14? Damn qz3fwd you have DVHS insanity. Do you use all 14 or have some for backup? I have 3 units, 2-JVC 40k, and a 5U. Still use them from time to time, but not as much now, as I use my Hauppauge.
post #8 of 117
I have backups of each model and basically one unit of each in up to 3 rooms.
I couldn't help myself and just wished I had picked them up when the decks were going for like $50 USD....
I just moved my Japanese AVHDD to my MacPro and wired it through the Mitsubishi 2K and DCH3416.
I want to add AVHDD support to the FirewireSDK. The AVCDevice class doesn't support hard disc recorder/player subunit (yet).
AVCInfo recompiling in xcode....
post #9 of 117
I also picked up the remaining stock of DVHS titles from the guys at the HDNet store earlier this year.
Some pics were posted in another thread somewhere in this sub-forum.
They still had like 20-30 copies left of various titles and they were more than willing to dump them to me.

I'm re-arranging my rack next to the TV (built with the frosted glass side facing wrong way up) but will try to post some pics with good lighting of the component rack, w/4 DVHS machines) this weekend if I get time.
post #10 of 117
Quote:
Originally Posted by qz3fwd View Post

I have backups of each model and basically one unit of each in up to 3 rooms.
I couldn't help myself and just wished I had picked them up when the decks were going for like $50 USD....
I just moved my Japanese AVHDD to my MacPro and wired it through the Mitsubishi 2K and DCH3416.
I want to add AVHDD support to the FirewireSDK. The AVCDevice class doesn't support hard disc recorder/player subunit (yet).
AVCInfo recompiling in xcode....

A true believer! HD recording is fun
post #11 of 117
What outputs do the hd cable box need to have to record to one of these d-VHS machines?
post #12 of 117
Quote:
Originally Posted by Stoney Jackson View Post

What outputs do the hd cable box need to have to record to one of these d-VHS machines?

You'd need to have an active FireWire (IEEE-1394) port on your cable box. Just because the box *has* a FireWire port, doesn't guarantee that it's *active*. You might inquire in one of the local forum threads to see if your provider does this (or can be convinced/have their arms twisted into doing it, or providing you with a box with a FireWire port that can be activated). The mandates about FireWire ports on cable boxes have been suspended, so unless there's some major change, expect this to become more and more difficult to make happen.

Also, if the programming in question is marked as "copy once" (aka "copy one generation"), you won't be able to copy that recording off that tape, so if the tape stretches/snaps/otherwise becomes damaged, the recording is gone forever.

Also also, keep in mind that D-VHS is a dead technology. No new recorders will be made, the only units available are existing stock/refurbed units. Tapes will be harder and harder to find. This probably isn't a long-term solution.
post #13 of 117
Quote:
Originally Posted by demonfoo View Post

You'd need to have an active FireWire (IEEE-1394) port on your cable box. Just because the box *has* a FireWire port, doesn't guarantee that it's *active*. You might inquire in one of the local forum threads to see if your provider does this (or can be convinced/have their arms twisted into doing it, or providing you with a box with a FireWire port that can be activated). The mandates about FireWire ports on cable boxes have been suspended, so unless there's some major change, expect this to become more and more difficult to make happen.

Also, if the programming in question is marked as "copy once" (aka "copy one generation"), you won't be able to copy that recording off that tape, so if the tape stretches/snaps/otherwise becomes damaged, the recording is gone forever.

Also also, keep in mind that D-VHS is a dead technology. No new recorders will be made, the only units available are existing stock/refurbed units. Tapes will be harder and harder to find. This probably isn't a long-term solution.

All true (I believe) ... and all worth considering. And it's just more confirmation of the universal truth ... that Hollywood wants you to buy their product. They just don't want you to have their product.
post #14 of 117
SVHS tapes can be used to record 1080i using DVHS machines. Millions of SVHS tapes floating around. Supply is not a problem.

I own 6 machines at last count. I'm betting I am good for my lifetime.

Then again I have eight minidisk recorders/players all in functioning condition. My HDDVD collection is up to 5 machines.

I love technology
post #15 of 117
I have a D-VHS Unit that i dont really use...
What is the best unit that i can purchase other than a cable box to record to my dvhs box./.......?
post #16 of 117
Quote:
Originally Posted by Star56 View Post

SVHS tapes can be used to record 1080i using DVHS machines. Millions of SVHS tapes floating around. Supply is not a problem.

I own 6 machines at last count. I'm betting I am good for my lifetime.

Then again I have eight minidisk recorders/players all in functioning condition. My HDDVD collection is up to 5 machines.

I love technology

I picked up another 40K from Gibbys for a steal last week. Brand new unit they got from JVC Canada who recently liquidated all of their remaining service stock!

I now have several 30K, 40K, 100U's and severl Mits 2000's. All brand new-some still sitting in the box.

I couldnt help myself when I saw the new 40K for $150 on their website.

I also got a still sealed "Mulholland Drive" DTheater from ebay for a steal, and a used American Pie DTheater from somebody who didnt know what it was worth. Now if I could find sealed "True Lies" "Bourne Identity" "American Pie" "X2" "Master & Commander" "Day After Tomorrow" I'd be all set.
post #17 of 117
Do sealed tapes play better?
post #18 of 117
Quote:
Originally Posted by qz3fwd View Post

I picked up another 40K from Gibbys for a steal last week. Brand new unit they got from JVC Canada who recently liquidated all of their remaining service stock!

I now have several 30K, 40K, 100U's and severl Mits 2000's. All brand new-some still sitting in the box.

I couldnt help myself when I saw the new 40K for $150 on their website.

I also got a still sealed "Mulholland Drive" DTheater from ebay for a steal, and a used American Pie DTheater from somebody who didnt know what it was worth. Now if I could find sealed "True Lies" "Bourne Identity" "American Pie" "X2" "Master & Commander" "Day After Tomorrow" I'd be all set.

You looking for this?

Nah its not sealed, or for sale....just yanking your chain.

Nice score on the 40k. Its like we don't want the gear to become orphans.
post #19 of 117
Quote:
Originally Posted by msgohan View Post

do sealed tapes play better?

Always....
post #20 of 117
I have a Mitsubishi 1100 DVHS paired with a MIT MDR-200 OTA tuner w/firewire. Don't record HD much anymore due to my Dish 622 DVR. However it is the best VHS DVR I have ever owned I expect to use the SD part for a long time.

Rick R
post #21 of 117
Quote:
Originally Posted by Blasst View Post

You looking for this?

Nah its not sealed, or for sale....just yanking your chain.

Nice score on the 40k. Its like we don't want the gear to become orphans.

I already have a used copy-like I said, I am looking for a sealed copy.
Please read along carefully.
post #22 of 117
Is it possible to record or transfer DVHS recordings of a firewire compatible DVR to Windows 7 or Vista x64 yet?
post #23 of 117
64 bit windows no.
64 bit os-x yes.
(Neither will allow you to transfer D-Theater protected tapes though)
post #24 of 117
I'm assuming you mean Linux? Ubuntu?
post #25 of 117
Quote:
Originally Posted by rocky01 View Post

I'm assuming you mean Linux? Ubuntu?

No I mean os-x as in snow leopard. Apple has a very nice firewire sdk which includes 64 bit support, which windows will never provide (64 bit that is).
post #26 of 117
Quote:
Originally Posted by qz3fwd View Post

No I mean os-x as in snow leopard. Apple has a very nice firewire sdk which includes 64 bit support, which windows will never provide (64 bit that is).

Never say never. I'd expect that, as 64-bit Windows grows in popularity, some clever person will throw together a 64-bit Windows driver.

But yeah, OS X already can do it (useless trivia: OS X is pronounced "OS Ten": OS X Prnounciation Video)
post #27 of 117
Quote:
Originally Posted by TNO821 View Post

Never say never. I'd expect that, as 64-bit Windows grows in popularity, some clever person will throw together a 64-bit Windows driver.

But yeah, OS X already can do it (useless trivia: OS X is pronounced "OS Ten": OS X Prnounciation Video)

Good luck with 64 bit MS drivers-not gonna happen.
You cant just be a clever person and throw together a driver, they would have to re-write the AVC driver from scratch which is a non-trivial task if you dont want your machine BSOD'ing constantly.
post #28 of 117
Quote:
Originally Posted by qz3fwd View Post

Good luck with 64 bit MS drivers-not gonna happen.
You cant just be a clever person and throw together a driver, they would have to re-write the AVC driver from scratch which is a non-trivial task if you dont want your machine BSOD'ing constantly.

It would take a very very talented programmer to do it, but I don't think it's fair to say that only MS (or someone with all the Windows x64 source code) would be capable of doing so.
post #29 of 117
Quote:
Originally Posted by TNO821 View Post

It would take a very very talented programmer to do it, but I don't think it's fair to say that only MS (or someone with all the Windows x64 source code) would be capable of doing so.

I did not say MS would have to do it.
The "clever" programmer would have to:
(1) have access to the AVC specs
(2) be a capable windows driver programmer
Neither is insurmountable, however since there used to be more demand than today exists, if someone was gonna do it, it most likely would have been done already. Maybe though.
post #30 of 117
Hi there. I just pulled my old 40000 out of the closet and am messing around with it by connecting the WORKING 1394 port of a Motorola 3200 HD Cox Cable tuner into the JVC.
I can see a clear picture with sound on ALL HD channels.
However, when I record, all I get back is a black screen with no audio.
Is it likely A) my record head has a giant headclog, or B) Cox is encrypting all HD channels, even the broadcast, OTA signals.
I'd expect them to do that with HBO, etc, but thought that OTA channels were in the clear.
What cable company to do you use?
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: HDTV Recorders
AVS › AVS Forum › HDTV › HDTV Recorders › D-VHS vs DVR for recording HD?