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post #1 of 39 Old 12-06-2007, 03:25 PM - Thread Starter
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I have an 52" Sony XBR4 and a Toshiba HD-A35 but my Yamaha receiver does not have HDMI input. However, it has optical input for sound.

Now I have heard people mention about using analog for sound but I am not sure what that mean.

1. Does analog mean that you use the component cables?

2. Which one would produce better sound....using optical or analog?

3. Also, for the future when I upgrade to a new receiver with HDMI inputs and has 1.3 HDMI capability, do I have to buy a special type of HDMI cable that does 1.3 or does any type of HDMI cable yield 1.3 features?
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post #2 of 39 Old 12-06-2007, 03:32 PM
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HD DVD player - connect HDMI to TV for video, HD DVD player optical out to Yamaha. This will give you surround sound, I have the HD2 and my yahama recognizes the sound as DTS - not sure what the A35 will down convert the sound to.
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post #3 of 39 Old 12-06-2007, 03:34 PM
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Quote:
Originally Posted by Vancomycin View Post

I have an 52" Sony XBR4 and a Toshiba HD-A35 but my Yamaha receiver does not have HDMI input. However, it has optical input for sound.

Now I have heard people mention about using analog for sound but I am not sure what that mean.

1. Does analog mean that you use the component cables?

2. Which one would produce better sound....using optical or analog?

Component is for video.

Your choices are analog (6 RCA cables from the analog out to the analog in on your receiver or digital (single optical toslink cable).

Analog > optical out for HD DVD because optical/digital doesn't have enough bandwidth for full resolution DD+ and TrueHD.

Not all receivers have analog inputs. Look on the back of your receiver for 6 RCA plugs labeled CENTER, FRONT L/R, SURROUND L/R, SUB.

If your receiver doesn't have analog in then you will need to go digital out (optical). Now digital out doesn't have enough bandwidth so the sound will be downgraded to 640K Dolby Digital. Don't worry this is still better than any SD DVD but analog or HDMI connection would give you better SQ.
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post #4 of 39 Old 12-06-2007, 03:39 PM - Thread Starter
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Originally Posted by namechamps View Post

Component is for video.

Your choices are analog (6 RCA cables from the analog out to the analog in on your receiver or digital (single optical toslink cable).

Analog > optical out for HD DVD because optical/digital doesn't have enough bandwidth for full resolution DD+ and TrueHD.

Not all receivers have analog inputs. Look on the back of your receiver for 6 RCA plugs labeled CENTER, FRONT L/R, SURROUND L/R, SUB.

If your receiver doesn't have analog in then you will need to go digital out (optical). Now digital out doesn't have enough bandwidth so the sound will be downgraded to 640K Dolby Digital. Don't worry this is still better than any SD DVD but analog or HDMI connection would give you better SQ.

Thanks, that was quite educational. Now if you could clarify the 1.3 HDMI thing and I would be set.

Also, do you know a good place to get good analog cable? Would monoprice be a good place? Do you have a specific link to a good analog cable (besides the Monster cable which is too pricey for me). I would still try to search myself but just in case there are cables out there that I may miss.
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post #5 of 39 Old 12-06-2007, 03:42 PM - Thread Starter
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Would this be a good analog cable?

http://www.monoprice.com/products/pr...seq=1&format=2

Do I buy six of these cables?
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post #6 of 39 Old 12-06-2007, 03:57 PM
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Quote:
Originally Posted by Vancomycin View Post

Would this be a good analog cable?

http://www.monoprice.com/products/pr...seq=1&format=2

Do I buy six of these cables?

you're looking for RCA cables, like these.

http://www.monoprice.com/products/pr...seq=1&format=2

i don't know if this is a top-quality product, haven't bought in a long time. but this is the kind of cable you need.

the cable you referenced is what you would use from the receiver to the subwoofer - you need one of those - but make sure it's long enough to reach wherever your sub is!
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post #7 of 39 Old 12-06-2007, 04:10 PM
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Quote:
Originally Posted by mikehalper1x View Post

you're looking for RCA cables, like these.

http://www.monoprice.com/products/pr...seq=1&format=2

i don't know if this is a top-quality product, haven't bought in a long time. but this is the kind of cable you need.

Those are stereo (dual channel) cables, so you could buy three of them. Just make sure you carefully re-label each cable to represent the six channels.

Or, you might consider paying a bit more for a pre-labeled 5.1 analog cable set, such as the Acoustic Research AP036 set at Amazon. Each channel of that set is individually color coded to match the Toshiba output and Yamaha input plugs. No difference in performance, just easer to hook up and keep straight.

Edit: Looks like forum sponsor RAM Electronics also has pre-labeled sets, with lower cost and additional length options. Part numbers: 55-509-6 and 55-509-12.
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post #8 of 39 Old 12-06-2007, 04:43 PM
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No, you don't need a 1.3 rated cable, but you can get a certified 1.3 cable from monoprice or blue jeans for so little, that you might as well.
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post #9 of 39 Old 12-07-2007, 09:39 AM
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Quote:
Originally Posted by namechamps View Post

Component is for video.

Your choices are analog (6 RCA cables from the analog out to the analog in on your receiver or digital (single optical toslink cable).

Analog > optical out for HD DVD because optical/digital doesn't have enough bandwidth for full resolution DD+ and TrueHD.

Not all receivers have analog inputs. Look on the back of your receiver for 6 RCA plugs labeled CENTER, FRONT L/R, SURROUND L/R, SUB.

If your receiver doesn't have analog in then you will need to go digital out (optical). Now digital out doesn't have enough bandwidth so the sound will be downgraded to 640K Dolby Digital. Don't worry this is still better than any SD DVD but analog or HDMI connection would give you better SQ.

Thanks for the information. I just bought a HD-DVD player and was wondering what would be the best way to hook it up. Right now I have it hooked up with an optical cable as my receiver doesn't have any HDMI inputs. However, my receiver does have 8 channel direct inputs.

If I were to hook it up this way, does the DVD player decode the audio and then would I be getting True HD or DD+? In other words, would it not matter what kind of audio formats my receiver is capable of? Also, this would then give me 6.1/7.1 (depending on what is on the DVD)?

*EDIT* Nevermind, my player doesnt have the analog out jacks. Is this unusual?
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post #10 of 39 Old 12-07-2007, 10:21 AM
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Originally Posted by Day Walker View Post

Thanks for the information. I just bought a HD-DVD player and was wondering what would be the best way to hook it up. Right now I have it hooked up with an optical cable as my receiver doesn't have any HDMI inputs. However, my receiver does have 8 channel direct inputs.

If I were to hook it up this way, does the DVD player decode the audio and then would I be getting True HD or DD+? In other words, would it not matter what kind of audio formats my receiver is capable of? Also, this would then give me 6.1/7.1 (depending on what is on the DVD)?

I will answer your questions because someone else may have same issue.

If your player has 6 channel analog out and receiver has 6+ channel analog in then the player and receiver are connected by a set of 6 RCA cables (one for each channel). There are no HD DVD player that have 7 or 8 channel analog out.

The player will decode the audio (DD+ & TrueHD) as full resolution analog audio. Your receiver will not "know" it is TrueHD or DD+ it will simply play the audio it receives. It doesn't matter if your receiver supports TrueHD or any format as by the time the signal reaches the receiver it is an analog waveform.

The highest audio you can support by this method would be 6 channel (5.1) TrueHD simply because no HD DVD player has 8 channel analog out.

The order of prefered connections (best to worst):
HDMI 1.3 bistream (allows DTS-HD MA not supported by player)
HDMI 1.1 PCM (same quality and can be used on any HDMI receiver)
6 channel analog out (high quality but may require an extra D-A conversion)
digital toslink (limited to 640K DD or 1.5Mbps DTS depending on player)
stereo RCA (high quality analog but limited to 2 channels)

Quote:


*EDIT* Nevermind, my player doesnt have the analog out jacks. Is this unusual?

Only the higher end players have 6 channel analog out (HD-XA2 & HD-A35). If the audio sounds good to you I wouldn't worry to much. 640K DD is still a huge leap over SD DVD sound.
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post #11 of 39 Old 12-07-2007, 10:25 AM
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Quote:
Originally Posted by namechamps View Post

I will answer your questions because someone else may have same issue.

If your player has 6 channel analog out and receiver has 6+ channel analog in then the player and receiver are connected by a set of 6 RCA cables (one for each channel). There are no HD DVD player that have 7 or 8 channel analog out.

The player will decode the audio (DD+ & TrueHD) as full resolution analog audio. Your receiver will not "know" it is TrueHD or DD+ it will simply play the audio it receives. It doesn't matter if your receiver supports TrueHD or any format as by the time the signal reaches the receiver it is an analog waveform.

The highest audio you can support by this method would be 6 channel (5.1) TrueHD simply because no HD DVD player has 8 channel analog out.

The order of prefered connections (best to worst):
HDMI 1.3 bistream (allows DTS-HD MA not supported by player)
HDMI 1.1 PCM (same quality and can be used on any HDMI receiver)
6 channel analog out (high quality but may require an extra D-A conversion)
digital toslink (limited to 640K DD or 1.5Mbps DTS depending on player)
stereo RCA (high quality analog but limited to 2 channels)



Only the higher end players have 6 channel analog out (HD-XA2 & HD-A35). If the audio sounds good to you I wouldn't worry to much. 640K DD is still a huge leap over SD DVD sound.

Thanks for the response. So there is absolutely NO way to get 6.1/7.1 with my current setup (optical) even though I have a 7.1 receiver? I'm pretty sure I was able to get 6.1 with my old standard DVD player with the few DVDs that had it (Lord of the Rings, Pan's Labyrinth).
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post #12 of 39 Old 12-07-2007, 10:35 AM
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Quote:
Originally Posted by Day Walker View Post

Thanks for the response. So there is absolutely NO way to get 6.1/7.1 with my current setup (optical) even though I have a 7.1 receiver? I'm pretty sure I was able to get 6.1 with my old standard DVD player with the few DVDs that had it (Lord of the Rings, Pan's Labyrinth).

Many Yamaha AVRs will let you force Dolby PLIIx to ON when using a 5.1 digital (optical Toslink) input. Look for a button on the remote control called EXT SUR (or some such IIRC) and cycle through its options. Forcing PLIIx on causes the AVR to matrix decode signals for the back surrounds from the side surround signals.

6.1 dts-ES, even though it can carry a discrete rear surround signal, essentially has the same info matrixed into the side surrounds.

I use PLIIx a lot to create a 7.1 soundfield for most all 5.1 digital signals (even DD-EX) with my RX-V2500.
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post #13 of 39 Old 12-07-2007, 10:43 AM
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Originally Posted by bobgpsr View Post

Many Yamaha AVRs will let you force Dolby PLIIx to ON when using a 5.1 digital (optical Toslink) input. Look for a button on the remote control called EXT SUR (or some such IIRC) and cycle through its options. Forcing PLIIx on causes the AVR to matrix decode signals for the back surrounds from the side surround signals.

6.1 dts-ES, even though it can carry a discrete rear surround signal, essentially has the same info matrixed into the side surrounds.

I use PLIIx a lot to create a 7.1 soundfield for most all 5.1 digital signals (even DD-EX) with my RX-V2500.

Interesting. I'm pretty sure I can force PLIIx with my receiver. Does this mean that the only signals that would be matrixed would be the back surrounds and everything else would be discrete? I never use the PLIIx mode because I thought that everything gets matrixed and I figured that a discrete 5.1 was better than a matrixed 7.1.
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post #14 of 39 Old 12-07-2007, 11:01 AM
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Quote:
Originally Posted by Day Walker View Post

Interesting. I'm pretty sure I can force PLIIx with my receiver. Does this mean that the only signals that would be matrixed would be the back surrounds and everything else would be discrete? I never use the PLIIx mode because I thought that everything gets matrixed and I figured that a discrete 5.1 was better than a matrixed 7.1.

I don't think PLIIx messes with the channels that are already discrete as far as what they output. But that is only IMHO.

We are diving into Audio theory, Setup and Chat forum subjects. Look for posts there by sdurani (Sanjay). For instance this one.
Edit: just found this better post on the subject of always using PLIIx by Sanjay.
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Originally Posted by bobgpsr View Post

I don't think PLIIx messes with the channels that are already discrete as far as what they output. But that is only IMHO.

We are diving into Audio theory, Setup and Chat forum subjects. Look for posts there by sdurani (Sanjay). For instance this one.
Edit: just found this better post on the subject of always using PLIIx by Sanjay.

Yeah, sorry for going off topic and thanks for the links.
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post #16 of 39 Old 12-07-2007, 11:40 AM
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Originally Posted by lassen View Post

Those are stereo (dual channel) cables, so you could buy three of them. Just make sure you carefully re-label each cable to represent the six channels.

Or, you might consider paying a bit more for a pre-labeled 5.1 analog cable set, such as the Acoustic Research AP036 set at Amazon. Each channel of that set is individually color coded to match the Toshiba output and Yamaha input plugs. No difference in performance, just easer to hook up and keep straight.

Edit: Looks like forum sponsor RAM Electronics also has pre-labeled sets, with lower cost and additional length options. Part numbers: 55-509-6 and 55-509-12.

Thanks for the helpful info! You just saved me 70 bucks. I almost went the 90 buck bluejeans cable route but these ones are a much better and reasonably priced option...

PSN ID: SCjohnny21
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post #17 of 39 Old 12-07-2007, 12:23 PM
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Originally Posted by namechamps View Post

Only the higher end players have 6 channel analog out (HD-XA2 & HD-A35). If the audio sounds good to you I wouldn't worry to much. 640K DD is still a huge leap over SD DVD sound.

I'm not a audio fanatic like many people here but I was very surprised at how much better DD+ sounds. When I first got my player, I had a ground loop problem which prevented me from using an HDMI cable, so I picked up a cheap optical cable and let the player downmix to 640K DD. It sounded as good as any DVD I've heard so I was pleased.

Once I fixed the ground loop problem a few days later, I tried the direct HDMI connection for kicks. I was amazed at how much better real DD+ sounded. It had a far more convincing surround effect and as I switched back and forth I noticed many subtle sounds in the DD+ track that I couldn't hear at all in the DD downmix.

Suddenly DVD and HDTV audio sounds so much weaker to me.

NOW: my post on AVS Forum.
NEXT: someone else's post on AVS Forum.
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post #18 of 39 Old 12-09-2007, 10:38 PM - Thread Starter
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Originally Posted by lassen View Post


Edit: Looks like forum sponsor RAM Electronics also has pre-labeled sets, with lower cost and additional length options. Part numbers: 55-509-6 and 55-509-12.

Thanks for the link.

However, I have a question.

The 55-509-6 is pretty cheap ($16.15):

http://www.ramelectronics.net/audio-...rod555096.html

but when I looked at the SACD5103 it is much more expensive at $98.42.

http://www.ramelectronics.net/audio-...odSACD51.html#

The biggest difference that I see is the "True 75 ohm." Will this feature give a noticeable improvement in sound quality? Would it be worth it to get a much more expensive cable?
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post #19 of 39 Old 12-10-2007, 12:59 AM
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75-ohm impedance is not important for analog audio.....only digital audio and video
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post #20 of 39 Old 12-10-2007, 01:33 PM
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Quote:
Originally Posted by Vancomycin View Post

Thanks for the link.

However, I have a question.

The 55-509-6 is pretty cheap ($16.15):

http://www.ramelectronics.net/audio-...rod555096.html

but when I looked at the SACD5103 it is much more expensive at $98.42.

http://www.ramelectronics.net/audio-...odSACD51.html#

The biggest difference that I see is the "True 75 ohm." Will this feature give a noticeable improvement in sound quality? Would it be worth it to get a much more expensive cable?

You don't want to use video cables for analog sound. Get the cheaper audio cable. RCA analog audio cable is designed for high impedance audio like you need.
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post #21 of 39 Old 12-10-2007, 02:13 PM
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Originally Posted by Videopark View Post

You don't want to use video cables for analog sound. Get the cheaper audio cable. RCA analog audio cable is designed for high impedance audio like you need.

Sorry but nothing true about those statements.
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post #22 of 39 Old 12-10-2007, 03:00 PM
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Quote:
Originally Posted by Videopark View Post

RCA analog audio cable is designed for high impedance audio like you need.


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post #23 of 39 Old 12-10-2007, 04:43 PM
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Originally Posted by ccotenj View Post


In modern amplifiers, unbalanced, line level analog audio is considered high impedance. Back in the old days when you had voltage-matched systems, the impedance was 600 ohms in/out using balanced connectors and circuits.

"Impedance (Z) is the resistance of a circuit to alternating current, such as an audio signal. Technically, impedance is the total opposition (including resistance and reactance) that a circuit has to passing alternating current.
A high impedance circuit tends to have high voltage and low current. A low impedance circuit tends to have relatively low voltage and high current."

"In most audio devices, the impedance of the line output is low -- about 100 to 1000 ohms. The impedance of the line input is high -- about 10K to 1 Meg ohms".

http://www.tape.com/resource/impedance.html

So I would not use a cable that was designed for 75 ohms in a unbalanced, high impedance circuit.
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post #24 of 39 Old 12-10-2007, 04:48 PM
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Originally Posted by rynberg View Post

Sorry but nothing true about those statements.

First true statement: Do not use 75 ohm coaxial cable for unbalanced, high impedance audio.

Second: Do not buy the expensive video cable listed in your question but purchase the cheaper audio cable for your audio application.

Third: The RCA audio cable you asked about in your question is the one to buy to interface your audio.

Fourth: RCA audio cable is designed for high impedance applications like the one asked about.
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post #25 of 39 Old 12-10-2007, 05:26 PM
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Originally Posted by rynberg View Post

75-ohm impedance is not important for analog audio.....only digital audio and video

It may be helpful to fully define your opinion. Digital audio for a coaxial connection using an RCA cable is 75 ohms. Digital audio on an XLR cable (AES-EBU standard) is 110 ohms.
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post #26 of 39 Old 12-10-2007, 06:20 PM
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Originally Posted by rynberg View Post

Sorry but nothing true about those statements.

I beg to differ. 75 ohm cable is needed for high MHz frequencies (digital audio & video) to have a proper impedance match per transmission line theory. Not neccessary at all for audio frequencies, IME.
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post #27 of 39 Old 12-10-2007, 06:26 PM
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Originally Posted by Videopark View Post

It may be helpful to fully define your opinion. Digital audio for a coaxial connection using an RCA cable is 75 ohms. Digital audio on an XLR cable (AES-EBU standard) is 110 ohms.

OK for unbalenced single ended cable that has 75 ohm source and sink impedances.

What you describe seems like a pro audio type thingy. Not for us mid-Fi consumer audio users.
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post #28 of 39 Old 12-10-2007, 06:38 PM
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Quote:
Originally Posted by Videopark View Post

In modern amplifiers, unbalanced, line level analog audio is considered high impedance. Back in the old days when you had voltage-matched systems, the impedance was 600 ohms in/out using balanced connectors and circuits.

"Impedance (Z) is the resistance of a circuit to alternating current, such as an audio signal. Technically, impedance is the total opposition (including resistance and reactance) that a circuit has to passing alternating current.
A high impedance circuit tends to have high voltage and low current. A low impedance circuit tends to have relatively low voltage and high current."

"In most audio devices, the impedance of the line output is low -- about 100 to 1000 ohms. The impedance of the line input is high -- about 10K to 1 Meg ohms".

http://www.tape.com/resource/impedance.html

So I would not use a cable that was designed for 75 ohms in a unbalanced, high impedance circuit.

nice informative link, but i'm not seeing how it's germane to the situation at hand... a great many quality interconnects are made of 75 ohm cabling...

i fully admit i might be missing something here, but i'm not sure what it is...

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post #29 of 39 Old 12-10-2007, 06:43 PM
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Quote:
Originally Posted by bobgpsr View Post

What you describe seems like a pro audio type thingy. Not for us mid-Fi consumer audio users.

maybe that's where my confusion is coming in... i've used 75 ohm coax interconnects for a very long time with no deleterious effects...

- chris

 

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http://www.avsforum.com/t/1332917/ccotenj-finally-gets-a-projector

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post #30 of 39 Old 12-10-2007, 07:04 PM
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Quote:
Originally Posted by ccotenj View Post

nice informative link, but i'm not seeing how it's germane to the situation at hand... a great many quality interconnects are made of 75 ohm cabling...

i fully admit i might be missing something here, but i'm not sure what it is...

The original question came from a user who was wondering if he should purchase a 75 ohm coaxial video cable to connect two audio devices. I said not to buy the expensive VIDEO cable but to buy the less expensive AUDIO cable.

Someone then disagreed with that advice.
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