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Beastus
03-14-2003, 12:03 PM
I have a Pioneer player that was issued in 94 or 95. It has a AC-3 RF output (that probably was added by the previous owner), but it doesn't have a regular digital output. Is that something you can add to it, or should I buy a new player?

Also, if I were to buy a demodulator and connected it into the AC-3 output, would that operate as a digital output into my receiver? Or is the AC-3 output only set set to detect those signals?

Paff
03-14-2003, 04:44 PM
Not sure what you mean by "regular digital output"

Do you mean a single coax or optical digital output, or the standard L/R Digital outs? Or, more simply, if you put in a non AC-3 disc with audio commentary, can you hear the movie or only the commentary?
Actually, a player built in 94 or 95 definitely would have a digital outputs. It's only the real old ones that don't.


Yes, an AC-3 output is ONLY for AC-3 signals. These signals are paradoxically carried on the Analog R/2 track (there are 4 tracks on a laserdisc: Digital L/R or 1/2, and Analog L/R or 1/2). Your AC-3 output simply grabs that signal (if it exists) and passes it on, RF modulated. The RF DEmodulator turns it into a Dolby Digital signal that your receiver can use.

The L/R digitals are your most important outputs, as all movies (except DTS ones) carry a soundtrack on those tracks.

I actually use THREE audio hookups with LD. My L/R for non-AC-3 movies, an AC-3 connection for Dolby Digital discs, and an optical for DTS tracks. There's no other way to do it. You can't have ONE cable for all 4 types of LD audio. It's because the audio systems developed over the lifespan of LD. First it was analog, then digital, then Dolby Digital, then DTS.

Beastus
03-14-2003, 08:32 PM
The model is CLD-D515. It may be a little bit older than I said. But I though it was from 94-95.

It has an analog audio output and AC-3 RF output. That's it.

Would I e.g. be able to play a DTS laserdisc, or would I need a digital output for that? Is worth upgrading to a player with a coax or optical out, or should I just use my analog outputs for now?

BTW, I don't get any sound from the AC-3 RF output, since I don't have a demodulator or one of those hi-end receivers that has a built in demodulator for RF signals.

And one other thing I've always wondered about. Why was the AC-3 output with RF signals. Wouldn't there any other way to do this, instead of people have first to buy a player with that output, only to invest in a demodulator to use it?

Paff
03-14-2003, 09:24 PM
Again, I think you have Digital outputs. Not digital in the vein of Dolby Digital or DTS, but Digital Coax L/R outputs.

It's real easy to tell. Just put in a disc with commentary, or AC-3, or something else on the Analog tracks. Commentary tracks are usually on the LD's analog tracks. If your player does not have digital outs, it would only read the analogs, and thus, you would only hear the commentary, not the film soundtrack.

Why the RF Modulation? Well, the AC-3 tracks were put on those analog tracks, not the digital. They did this so that when they released AC-3 discs, those without modified players and/or Demods could still enjoy the LD's sound. I guess at the time it was standard to have an RF input on a Dolby Digital receiver, so it was no big deal. Obviously it is not standard now.

You would need a single Digital Output (coax or optical) for DTS discs. However, DTS discs are quite limited, and are only getting more and more expensive. I only have 5. If you don't plan to buy any DTS discs, I'd stick with a player with those Digital L/Rs.

Again, just pop in a disc with commentary. If you can listen to the film normally, you have digital outputs.

bigdaddyhorse
03-14-2003, 09:40 PM
Let me get this all straight, I have a piece of crap Quasar player right now. It only has the rca outputs in back, which I'm running rca cables into my stereo for. I can flip through all the digital and analog channels to hear any sound option on the disc, but the tracks with the movie soundtrack all sound the same, even in stereo digital or stereo analog (without commentary of course).
I'm not sure how old this player is, it does have S-video.
What would happen if I put digital co-ax cables instead of rca cables? I don't have any DTS lasers, so I'm not worried about getting DTS, just a better Pro-logic sound.
I'm about to have a new player anyway, but this thread made me curious if I have digital outs and didn't know it.
I know digital co-ax and rca jacks look about the same, but I don't remember anything near the jacks saying anything about digital, just right 1 and 2, left 1 & 2.

Paff
03-14-2003, 10:02 PM
Originally posted by bigdaddyhorse
I can flip through all the digital and analog channels to hear any sound option on the disc

If you can do that, you have digital outputs. It's that simple. Analog outputs only allow the signals on the analog tracks. Commentary tracks are the easiest way to prove it. If you can turn the commentary off/on, you MUST have digital outs.

The thing that gets everyone confused is Dolby Digital, and Digital Theater Sound (DTS). The Digital outs provide you with Digital PRO LOGIC, which is quite different than DD (AC-3 or 5.1) or DTS. Since that Digital Pro Logic really doesn't exist with DVD, it throws off most newcomers to LD.

Yes, the Digital and Analog tracks sound pretty much the same. I've never compared them directly, maybe they sound exactly the same. Hard to say.

I'm not sure what you mean by Digital Coax cables vs. RCA. Cables are cables. It's the actual signal itself that matters. A coax cable is a coax cable, and can pass analog or digital signals. As long as your cables are good, that's all you need.

Paff
03-14-2003, 10:04 PM
Oh, and to make things a little more confusing, the signal at those L/R outputs is indeed analog, but they've been converted to analog by the player itself. THe track they read is digital. The older players can't read the digital track and convert to analog, so they just pass the analog tracks staight through.

The reason BDH may not notice a big difference between Analog and Digital is that his Quasar player has poor D-to-A convertors.

Beastus
03-15-2003, 10:38 AM
Thanks for clearing that up, Paff. I indeed have digital outputs then (although it's sent as analog into the receiver), as I'm able to listen to the digital tracks on the laserdisc. Doesn't have any plans to buy DTS discs at the moment, but it would be fun if I was able to play them, just in case I wanted to try 'em out.

bigdaddyhorse
03-17-2003, 09:30 PM
My question about the cables was because I always thought the regular RCA cables only carry analog singnals. If I could just plug one RCA cable into my dvd player to use as a digital coax I'm gonna be pissed!:fuck: I was under the impression that they were wired completely different inside, and weren't interchangable. Like you need a digital cable for a digital signal. Is that right or just a way for companies to jack up the price by calling a cable "digital"? You can get a set of 3 6 foot RCA cables for about 3 bucks, but a 3 foot digital coax is $10 for the cheap brand!

Paff
03-17-2003, 09:57 PM
Originally posted by bigdaddyhorse
If I could just plug one RCA cable into my dvd player to use as a digital coax I'm gonna be pissed!

Yup, would have worked. Try it!

Personally, I use better cables on my digital signals as a matter of principle. What I use are gold-plated coax video cables. They're about 5 bucks at Radio Shack. Not as cheap and flimsy as the typical coax cable, but not as overpriced as the Monsters.

With the exception of opticals and S-Video, cables are cables. If it's RCA on both ends, that's all that matters. Now, you want GOOD RCA cables, but when you bought "digital coax" you paid extra only for those words. Sucks, huh?

bigdaddyhorse
03-17-2003, 10:08 PM
GODDAMNIT!
Fucking rapists, at least I got the cheap $10 version. I'm sure it probably sounds at least a little better than an rca, but I hate paying for words!:mad: :fuck: :mad:
Monster digital coax cables have to be the biggest ripoff going in home theater, those were fucking $50+ for one 6 footer! Glad I didn't go that route!
Shit, I'm gonna look into buying stock in them!:D

Beastus
03-18-2003, 10:26 AM
I'm going to try that when I come home. But that makes me wonder. If I was to connect one RCA cable into my digital input, I would only get a mono sound right. Maybe I would need 2 RCA cables (one red and one white) which ends in one jack. That way I would get a stereo sound probably. Am I right?

Paff
03-18-2003, 05:56 PM
Naw Beastus, what BDH is talking about is the digital outputs on DVD players. For that, you don't need a "special digital RCA cable".

For LD players with the L/R outs, you'll still need two RCA cables. Now, if you have a single digital coax out (many LD players don't), then yes, you can get by with one cable.

I've heard of some people who just use the optical out for LD sound, but since that doesn't allow access to the analog tracks, you can't listen to commentaries that way.

Blade
03-29-2003, 02:13 PM
I'm lookin into buying a second hand laserdisc player myself, and it will likely be some Pioneer model with optical output. I have a Sony receiver/dvd player, which can output DD and DTS audio tracks, and has optical input.
My question is, what laserdisc audio tracks can I listen to, by just hooking the LD optical out directly to the Sony optical in?
I can't really figure it out by reading the previous posts, because they work a little confusing...

jscott
03-29-2003, 02:54 PM
Originally posted by Blade
My question is, what laserdisc audio tracks can I listen to, by just hooking the LD optical out directly to the Sony optical in?
I can't really figure it out by reading the previous posts, because they work a little confusing...

Now it's gonna be a little confusing, but I'll try my best (I'm sure Paff could explain this better, but I think he's still asleep). There are two different types of digital audio outputs on Laserdisc players. One is PCM audio, which can only produce Dolby Pro Logic surround sound, DTS audio, and stereo. The other is AC3 output, which can only be used for Laserdiscs marked AC3, or Dolby Digital, but no other sound format can be output from the AC3 jack (no matter if it's mono, stereo, or Pro Logic). Just so you know, Dolby Digital audio on Laserdiscs is not the same as Dolby Digital on DVD's. Unless your Sony receiver is a few years old, and one of the Digital inputs is marked AC3, you will not be able to listen to AC3 tracks from the Laserdisc player unless you buy an RF Demodulator, or if you have an LD player that converts the AC3 signal to a Dolby Digital signal internally (but I'm not positive there's any LD players capable of doing so). In a nutshell, it's a box that turns your AC3 signal into a Dolby Digital signal that modern day receivers can read. Now to answer your question specifically, if you use a Digital PCM output to your receiver, all the receiver will be able to read are the Digital audio tracks on the disc, which means no hearing the analog commentary tracks on your stereo. Also this can be bad for older LD titles that don't have any Digital audio tracks whatsoever (My Father's Star Trek original series LD's come to mind, no PCM audio, just analog, which means you need a set of L&R RCA cables) What may have confused you is that AC3 audio tracks are located on the Analog audio track, even though they're a Digital signal. I really hope this helps, if not, quote the sections you don't understand, and I'll try & break it down.

Blade
03-29-2003, 03:11 PM
Well, I've been doing a little more reading on this forum, and it seems that Dolby Prologic Surround on LD's often sounds as good as 5.1 DD? If that's the case, that means that I don't need one of those way to hard to find (I live in The Netherlands) demodulators, if I'm not mistaken. But, what audio outputs does the LD player need to pass the Prologic signal to my Sony receiver? (it's a brand new Sony DAV S-800 receiver btw, so I guess it won't be able to do anything with AC3 sound from LD's)

And specifically, I have recently won the 5.1 Star Wars LD set (Special Edition set, 1997, the one with the black box and a picture of Vader in the middle) on ebay (for 25.50 dollars). Can I listen to it in some form of surround, without a demodulator? (like is there a Prologic track present on that particular version of the Star Wars LD's?

jscott
03-29-2003, 03:30 PM
Most of the time yes, Pro Logic sounds as good as DD. If the Laserdisc player you buy doesn't have a PCM Optical output, you can still get Pro Logic audio through the analog L&R jacks (just like on a Hifi Stereo VCR), but it does sound better through a Digital connection.

As for the Star Wars boxset, I don't own it myself, but most of the LD's I have with an AC3 track also have a Pro Logic track, so it shouldn't be a problem to get Pro Logic surround from those discs.

jscott
03-29-2003, 03:45 PM
One more thing Blade. In case you were wondering, your receiver should be able to read a PCM signal through it's digital inputs. I know my Onkyo receiver can read PCM & DD/DTS signals in the Optical input. The receiver automatically switches to whatever Digital format is input.

Blade
03-29-2003, 03:49 PM
That's great news! But, do the prologic tracks make use of sepperate right left rear speakers? I believe it's just one signal, not two, that are send to the rear speakers, correct? And does prologic surround mke use of the front center speaker? Damn, I thouht I knew how prologic worked, but reading about laserdisc player confuses me.

Anyway, It looks like I can choose between the following LD players, all will probable cost around 100 dollars, some more, some less. Could anyone give me an indication on their quality?

These are the models:

- Pioneer CLD-1050
- Sony laserdisc recorder (doesn't say which model nor does it have a picture, maybe there's only one model?
- Pioneer cld 1850
- Philips type CDV-185
- Pioneer cld-d515
- Pioneer CLD-1750 (I think this is a good one?)

Thanks for all the help so far.

jscott
03-29-2003, 04:05 PM
Originally posted by Blade
That's great news! But, do the prologic tracks make use of sepperate right left rear speakers? I believe it's just one signal, not two, that are send to the rear speakers, correct? And does prologic surround mke use of the front center speaker? Damn, I thouht I knew how prologic worked, but reading about laserdisc player confuses me.

Most new receivers have Dolby Pro Logic II, which separates the rear L&R signals on Pro Logic audio tracks(not sure of the technical mechanics of it, but it sounds pretty damn good). As for the Center channel, yes, it works just like DD on DVD (dialogue from the center, etc...), the major difference is that 5.1 has a separate, isolated subwoofer track (or LFE as it's called). Pro Logic just puts the bass with the main speakers, but if you have a subwoofer hooked up to your receiver, then you probably have the receiver set up to filter the bass from your main speakers into the subwoofer.

As for the quality of the models you have listed, Paff & the others would be able to help you out more than I. The only models I know anything about are the Pioneer CLD-___ series, but I'm not familiar with any of the CLD models that you listed.

Paff
03-30-2003, 08:49 AM
Actually, JScott's first response (bottom of Page 1) is pretty much spot on.

For the Digital Outputs, you can use either the optical out or the L/R outs. Neither one will give you Dolby Digital 5.1, and as already mentioned, if you use the optical, you won't be able to access commentary tracks. I'd say go with some good L/Rs

As far as the split surrounds, you won't get that with Pro-Logic. You're right about the surrounds being only one track. It kinda sucks, but for except for the rare times you want split-surrounds, it's not that huge of a deal. You WILL get a separate center signal though.

The thing about Dolby Digital vs. Pro-Logic is that there's really little difference with the two formats on LD. That's not true on DVD, where Dolby Digital blows away Pro-Logic. Dolby Digital does sound a little better on LD, but the differences are subtle.

As far as the players you list, hard to say as they're all European, and I know Jack and Shit about Euro players.
Avoid the Sony at all costs, they were the worst LD players. For the Pioneers, verify that the player is two-sided. You don't wanna have to get up and flip the discs on every single movie.

Blade
03-30-2003, 02:26 PM
Thanks for all the help, it's all pretty clear to me now.

Too bad there's really little information on European laserdisc players available on the internet, that makes it pretty hard for me to choose. But based on general opinions, Pioneer is the way to go.

I do have a question about demodulators. If my reveiver has this:
- Dolby Digital RF Input for Dolby Digital decoding with compatible Laserdisc players -
does that mean that I don't need a demodulater when my LD player has AC-3 output?

Paff
03-30-2003, 05:57 PM
Originally posted by Blade
I do have a question about demodulators. If my reveiver has this:
- Dolby Digital RF Input for Dolby Digital decoding with compatible Laserdisc players -
does that mean that I don't need a demodulater when my LD player has AC-3 output?

Yup, you're in the clear! No demod needed whatsoever!
Just a good cable from the LD's RF output to the receiver's RF input and you're all Dolby Digitized

(You'll still need a L/R connection for non-Dolby Digital LDs though)