Options for Wiring an Oppo

**Bob in St. Louis** · **01-26-07, 12:48 PM**

I've been looking at the Oppo 971 and am deciding how I should wire it.
I'd like you guys to see if you find any glaring problems. I've got two ideas, one the video signal might suffer (cable lenth), the other audio might suffer (cable lenth). And other general advantages/disadvantages to each wiring option.

Option #1: Put the Oppo in the rack with the rest of the equipment. The audio cable run would be about 2'. The Oppo DVI output to HDMI input of the receiver. Then HDMI output to the DVI input of the projector.
Advantage: Short Audio run. Receiver is now the video switching unit. Receiver DOES have the ability to adjust video/audio sync delay.
Disadvantage: 25' long video run. Two video cables used (4 terminations) more possibility of signal loss. Cost of HDMI/DVI cables.

Option #2: Put the Oppo within a few feet of the projector. Oppo HDMI output to DVI input of the projector. Cable lenth, about 6'. Run the audio via RCA to the receiver 25' away.
Advantage: Short Video run.
Disadvantage: Long audio run. Lose the ability of video switching in the receiver. "POSSIBLY" losing the ability of using the on screen menu for the receiver?

Any ideas, thoughts, critisisms?

Here's links to the back plate of each component:

Oppo 971:
http://www.oppodigital.com/opdv971h_images.html

Harman Kardon AVR 645:
http://harmankardon.com/back.aspx?pr...me=AVR645B.jpg

Sanyo PLV Z2:
http://projectorcentral.com/pdf/projector_spec_2239.pdf

Bob

**Sonnie** · **01-26-07, 10:42 PM**

I'd place it in the rack with the rest of your equipment. The long video run is really not a problem with a minimum quality HDMI cable. Mine if 25', pretty decent quality and I don't think I paid more than $30-40 ... maybe less... it's been a while.

**basementjack** · **01-30-07, 03:56 PM**

I'll second Sonnie,

Put it in the rack - get some low cost DVI cables from monoprice.com, pimfg.com, or ebay.

I've considered the oppo, but now I'm wondering if I'd be better off with an HD-DVD player instead - they can be had for around $400 on the shack store (amazon), and I think they up-convert DVD's too. when you figure the oppo is $200, an extra 200 might be worth it (It is worth it if you don't have a player yet - Picture and sound Quality is amazing) I have the xbox 360 HD drive and it looks great, but sound is limited to dolby digital downmixing.

As an added bonus, A single HD dvd drive that upconverts would save space over the existing DVD player, and that tiny Xbox add on drive, which I can't stack anything on, and is too big to share space with the 360 on the shelf.

**Bob in St. Louis** · **01-30-07, 04:24 PM**

Ok Jack, HOOOOOLD THE PHONE!!!

Looking at the specs on the 971, it appears it IS HD.
I really didn't want to spend $400 for "the latest and greatest". I prefer to let everybody else be the guiney pig, and let the price come down a bit... (which is why I'm "late on the scene" buying an Oppo.)
If the 971 is NOT HD, how much better is the video quality on a true HD unit?
....Also keep in mind my projector specs too....
Please enlighted me

Bob

**basementjack** · **01-30-07, 06:03 PM**

by HD, I meant, plays HD-DVD software - I have a few movies in HD and they look terrific.
they would look better on your sanyo, since thats 720p.

The $400 toshiba HD-DVD player plays both SD - upconverted, as well as HD-DVD.

**Sonnie** · **01-30-07, 06:41 PM**

And the SD is excellent IMO... although I have no idea how it compares to the Oppo.

**fibreKid** · **01-31-07, 01:48 AM**

A new 971 might be hard to find. Last week the oppo site said discontinued and tonight I see only refurb units. Have you looked at the 981?
I have also seen the Toshiba HD-A1 for $349.00 US. It's a steal if legit.

Good luck
-john

**Bob in St. Louis** · **01-31-07, 10:01 AM**

Alright guys, thanks for the info.

fibrekid, I like the 981.
However - Money slowly seeps into my wallet, but flows out freely.

I know it's only $90 more, but ..... $90 is $90 I could use for more stuff.

Unsure how much better the 981 would be on my projector??

UPDATE: availability on Oppo products...All in stock as of today. The 971 is refurbished, but maintains the full factory warranty.

decisions.... decisions.... decisions

Bob

**Bob in St. Louis** · **02-16-07, 12:51 PM**

Ok, I'm going with Johns (fibrekid) recommendation, the Oppo 981.

Just to make sure (I'm slightly paranoid, I've never messed with HDMI)...Can I wire the 981 from HDMI to the receivers HDMI input, then out from there to the DVI input of the projector?

Now, I suppose I'd get the free 6' HDMI to HDMI cable, then buy a 25' HDMI to HDMI cable, then buy an adaptor that goes from HDMI to DVI.

Any thoughts?

Bob

**Dbeistel** · **02-16-07, 09:06 PM**

Bob,

Will your receiver pass a 1080p signal from the OPPO 981 if so buy the HDMI to HDMI from OPPO to Receiver and then buy a 25' HDMI to DVI cable from the receiver to projector and skip the adapter.

**Bob in St. Louis** · **02-17-07, 06:59 AM**

I thought about tha Dan, (I hate using adaptors), but I thought I'd future proof the wiring in case I upgrade to an HDMI projector someday. Not that the wire is that expensive, It's just a huge PITA to run wires from receiver to the PJ.
Don't know about the receiver and the 1080

. I assumed so since it was HDMI? I'll have to check the video specs again. (Later, because I'm running late for work

)

Bob

**basementjack** · **02-17-07, 05:29 PM**

It may be too late, but the best future proof in the world is an empty 2 inch pipe...

Tip - if you use PVC, avoid sharp 90 deg turns - 2x 45 with a few inches between work great.
Tip - if you can't run a fish tape due to a 90 deg turn you could not avoid - hook up a vacuume on one end. and feed kite string through the other - the suction will pull it through. Once you have the string, use that to pull the 'real' wires.

**Bob in St. Louis** · **02-18-07, 05:42 AM**

Jack, that is very good advise. It is advise I tell people whenever I can. I did have a few spots with conduit, but not as many as I thought as I was going to need. When I started this room, I wasn't a forum member anywhere and didn't know I was going to tweek and tweek and tweek......

My wife didn't expect this either

HA HA HA

Bob

**SteveCallas** · **02-21-07, 11:53 AM**

I'll offer an opposing viewpoint yet again

First off, why would you be running RCA audio from the dvd player to your receiver? You'll need digital coax or optical to transmit digital sound such as DD or DTS. Second, DVI and HDMI runs are transmitting signals over copper, and while 25' isn't that long, copper is definitely more prone to signal loss than fiberoptic cabling, that's why fiberoptic cabling and not copper is used to transmit signals across oceans. I'm also a bit weary of routing video through receivers even when the bandwidth is high....no facts to support a reason not to, just me being paranoid on that issue. My choice would be option #2, but my main objection here is that you shouldn't be using analog RCA cables from your dvd player to carry audio either way you go

**Bob in St. Louis** · **02-21-07, 12:34 PM**

Quote:

why would you be running RCA audio from the dvd player to your receiver?

I really don't know Steve.....

...but I would fully expect for somebody to slap me real hard in the temple if I did that.

The Oppo's have optical, (and I knew that), but I....Ahhh....Ummm...Well, I don't know what to say Steve.
Anybody that runs RCA that far is...

The unit will be hear on Saturday (the 981). It will be in the rack using all digital IC's.

Bob

**Bob in St. Louis** · **02-21-07, 12:35 PM**

Please don't laugh at me....

Bob

**jackfish** · **02-21-07, 06:14 PM**

You might want to consider using the coaxial output for your audio instead of optical. There are trade offs to be sure but overall I think there is better sound using coaxial connections for digital audio.

**SteveCallas** · **02-21-07, 08:14 PM**

Quote:

Bob wrote:

I really don't know Steve.....

Quote:

Please don't laugh at me....

Not at all, no worries

Quote:

jackfish wrote:

There are trade offs to be sure but overall I think there is better sound using coaxial connections for digital audio.

Unless one cable is defective, they will sound identical, as there will be no difference in the signal the processor is receiving. The advantages optical has are that it can't carry a ground loop and isn't as prone to signal loss. For all intents and purposes though, either one will work just fine.

**basementjack** · **02-21-07, 11:53 PM**

Quote:

SteveCallas wrote:

... why would you be running RCA audio from the dvd player to your receiver? ... my main objection here is that you shouldn't be using analog RCA cables from your dvd player to carry audio either way you go

If the player can play back either SACD's or DVD-Audio -then you need both Analog and digital cables - as those audio formats are typically decoded in the player and not in the reciever (there are a few exceptions, but it is rare/$$$) This 6 channel analog output goes to the 6 channel input thats on most newer receivers.

Length of audio cables isn't a factor - the DVD player is likely to be in the equipment rack with the receiver so only short analog cables are needed. you're not running audio to the projector....

And of course you'd still want the digital cable so your reciever can decode the Dolby Digital or DTS signals.

- Jack

**jackfish** · **02-22-07, 01:55 PM**

Quote:

SteveCallas wrote:

Unless one cable is defective, they will sound identical, as there will be no difference in the signal the processor is receiving. The advantages optical has are that it can't carry a ground loop and isn't as prone to signal loss. For all intents and purposes though, either one will work just fine.

Maybe to your ears.

Quote:

Optical (or Toslink as it is sometimes known) tends to introduce a considerable amount of digital jitter. What is jitter? Think of jitter as a miss-timing of the digital data. All the "1" and "0" of the digital data are the same but their time relationships have changed. Jitter messes up the word clock. Any digital output has digital jitter, it's just a question of how much. Optical has the highest jitter.

Quote:

This is a fact with digital datastreams where the word and bit clocks are embedded in the audio data. Toslink's more limited bandwidth shifts the transition timings, which define the difference between "1"s and "0"s on an AES3 or S/PDIF datastream.

Quote:

The problem with TosLink is that the bandwidth is insufficient to allow the timing of the data transmission to be retained. Bandwidth limiting causes timing errors in the zero voltage crossings used by the DAC to determine the timing of the signal.

I think the confusion some have is that bandwidth in this context has nothing to do with how much data is being transferred. In the context of an audio digital interface the frequency bandwidth is like voltage slew rate. An infinitely high frequency bandwidth would allow an interface to pass a perfect square wave of 1’s and 0’s with absolutely vertical “legs”. However when the bandwidth is too low, such as with TosLink, the legs become skewed in reference to time, causing timing errors.

An optical cable can carry lots and lots of data and in this way can have a high data bandwidth. At the same time the cable can have a limited frequency bandwidth and, consequently, a high level of timing errors. These timing errors make no difference in all digital systems, like the inside of a computer or inside of a digital phone system. They also don’t matter when the process of transforming the bits into an analog signal is not dependent on the timing of the arrival of the bits. However these timing errors matter when a DAC receives a digital audio signal in a high resolution audio system.

TosLink incorporates a plastic optical fiber and possesses a relatively low bandwidth. Glass optical fiber has a higher bandwidth and is superior to TosLink. Coax is better than TosLink as coax has a much higher bandwidth. AES/EBU is better at rejecting noise.

Go with a decent quality 75 ohm shielded coax digital transmission cable.

Quote:

The numbers are there to prove the jitter argument. Besides, why waste time converting from electrical to optical and back if you don't have to? Open up any single box disk player and I highly doubt you'll find even one that uses optical connections internally. The TOSLINK optical really only makes sense on portable equipment where space is a concern. Otherwise just use the coax. The bandwidth argument is kind of silly as well when we're talking about digital signals in two different domains- optical and electrical. Maybe you can squeeze more bits through the optical over long distances but if it's a 1 or 2 ft. piece of cable carrying relatively low bandwidth digital audio signals whats the use of converting the data stream into the higher bandwidth optical just to send it a foot or two to another component and change it back again? This one just seems to be a no brainer. If the signal were somehow kept in the optical domain from the disk to the jacks it might make sense I guess. Speaking of which, another issue with optical is the typically very poor jacks that don't really make very nice connections and probably introduce "optical impedance errors" where say, a glass fiber has a slightly different optical characteristic than a polymer one. By the way, if TOSLINK optical is so great why haven't the computer companies jumped on the bandwagon?

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