Optical vs Coaxial - Page 2

If you are looking for superior analog bypass I would look at the Bryston SP2 or a used SP1.7. I just sold my SP1.7 last month because I switched over to a purely digital preprocessor (Meridian 861) for my HT so I could have room correction and bass management at the expense of analog fidelity, but I would recommend it hands down if you don't need those features. It has analog bypass for both 5.1 and 2 channel signals. It isn't a receiver though, so you would have to buy amplifiers as well...

On a (hopefully) related topic:

I need to switch my connection between DVD player and receiver from "Optical" to "COAX". While I have full sound using the optical cable, unplugging it and using the COAX cable is unsuccessful: no sound and from the display on the receiver I can tell that the receiver is not recognizing the COAX cable. This leaves me puzzled as in the SETUP menu of the player, both optical and COAX are treated as "Digital" and cannot be "activated" separately. Any thoughts?

Are you using a digital RCA cable in the COAX slot? The cable needs to be "rated for digital use" and some analog RCA cables are not.

On Onkyo/Integra products (I own one) it is called "Direct" (which bypasses all processing) and (on some, I don't know about the 600 series) "Pure Audio" (which bypasses all processing and turns off all circuitry--including the display--that could "potentially" interfere with the pass through signal) "Direct" is sufficient to avoid processing. Otherwise, the receiver applies an A/D/A to the signal and then applies whatever DSP setting you have activated.

Some products (including some high end gear) do not have a bypass and do an A/D/A on ALL incoming analogue signals. The merits (or lack thereof) of such an approach are hotly debated.

No, all it should be is a 75-ohm cable, such as any decent video cable. There is no such thing as a "digital" cable, although marketers would have you believe different.

To be fair, his point about some RCA cables not working is correct (though your point about 75 ohm cable rating is also correct). I've saved a ton of cable money over the years by buying 75 ohm rated red/white/yellow sets instead of the more expensive (yet identical, for sometimes twice the price) red/green/blue sets for component video. Sadly, few cable vendors indicate an ohm rating and go with misleading labels instead.

Actually, it has been demonstrated that even a coat hanger will pass digital audio signals, error free. But, it is easier to use what you suggest already insulated, etc.

But most coat hangers have a heavier gauge than the lowest quality audio cables, so I'm not surprised.

Thank you: Yes, I am. It is a Digital Audio Coaxial Cable from Philips.

Yes, but it has no characteristic impedance, certainly not 75 ohms.
And, it may have been steel wire.

Not sure I understand exactly what you did.
Did you go into the receiver menu and set the DVD player from Optical to Coaxial?
Or did you go into DVD player menu and change it from Optical to Coaxial?

Not sure about your DVD player, but on my Denon Receiver I must set it to either Optical or Coaxial for the DVD input.
Bob

I found it, thank you. I had only been looking in the menu of the DVD Player - not at the receiver's. I appreciate your prompt response.

Does anyone know what is the maximum length allow for Toslink and/or SPDIF?

Monoprice is selling up to 50ft long version. I checked Toshiba website and was told the max is 10m (32ft)?

Or if you don't use full-range speakers and rely on a sub for the bass, then the receiver's DACs will be used (defeating the purpose of the CD analog outputs).

(This was following up on the last message of page 1; I hate it when that happens...)

I had used one of those cheap ass video cables that comes with DVD players, you won't find a worst and thinner cable anywhere. It worked.

I've used standard RCA cables for that purpose (digital connection) with no trouble but I did have one, very thin, cheapie cord not work (though it worked with analogue audio w/o any troubles).

For component video transmission, though, I've had several experiences where the signal is not carried properly, so I always use 75 ohm rated cables (though I go with the least expensive ones that I can find) for video purposes. Perhaps I did not express myself clearly with reference to the digital audio cable, though, as I meant only to say that a 75 ohm rated cable should ALWAYS work (barring some defect in the cable) and thus that rating is a good guideline.

The "heavy gauge" coat hanger comment was in jest.

Copy that.

in the early 90's with the advent of optical digital connections, many thought the speed of light would usher in a new era of high end audio. It didn't, even though many custom exotic fabrications of different type of glass compounds were experimented with. Fact is, most of my circle of audio enthusiasts found optical to in fact be softer sounding, less detailed and dynamic.

my experience when using toslink vs good old analog from any source to my sony home theater is good old analog rca inputs are louder by at least 30%.
forget using a 3 way toslink switcher being its lossy too.
i haven't tried coax yet.
barry

That would mean that the optical cable somehow, intelligently is capable of affecting dynamic range and frequency response, right?

I'm guessing the output is just a little less when running through the optical, Charles.

But it has worked just fine, in tests

How is that switcher lossy?

It also depends on what is meant by "optical."

Toslink optical has higher jitter than coaxial.

AT&T ST optical is a better interface than coaxial.

Don't forget that when dealing with digital audio, it's not only important that the digital data reach the DAC but just as important is the timing at which the bits are transferred and the accuracy of the clock signal encoded in the data stream, which is why jitter is important.

Which is not the same as saying that a system with a toslink digital connection has more jitter than it the connection was coaxial.

The digital agenda that seems to be hidden from many is the fact that as long as digital information is not too badly messed up, it can be totally and completely reconstructed and made perfect again.

For example, the digital information that comes off of a CD or DVD player's digital pickup is a bit of a mess, and definately full of jitter.

The recipie for cleaning this mess up dates back dozens of years before the first CD player was sold in late 1982. You clock the data into a data buffer as it arrives, and clock it out with a precision clock. That's what *every* CD player does, even the $8.95 special that they are advertising in the paper this weekend.


Agreed, but that's what you should do when you want to send a digital signal from city to city, and not just from your DVD player to the receiver that is sits right below it.

Also, ST optical cables are called on to do something far more complex than transmit 8 audio channels. Phone systems are based on running thousands or tens of thousands of channels concurrently down one piece of fiber.

The world is full of people who would like to sell you a cruise ship when all you really need is a good pair of boots. Use the right tool for the job. Audio isn't rocket science.



Right, but again rememeber that correcting the timing of digital signals is one of the oldest tricks in the book, and every CD and/or DVD player you ever bought did it for no extra charge.

So, what's your point - louder is better?


I'm sure a few photons get lost along the way. Can it possibly make an audible difference other than go/no-go?


I have. It can work. Use the best tool for the job, which is very often Toslink.

When you use the CD player's DAC's you are hooking up the CD player's analog RCA jack outputs.. when you use the receiver's DAC's you are hooking up optical OR coaxial digital to the receiver from the CD player.. in my experience Coaxial always sounds better than optical and alot of times if you use the analog output stage of a good cd player with the Cd player's RCA audio jacks.. (for instance my McIntosh LD/CD player) you almost always get a better sound than the digital outputs.. just my .02!

Mike

Jitter - (7 addresses optical vs coaxial):

http://www.positive-feedback.com/Issue43/jitter.htm



Coaxial has always sounded better to me than Toslink or HDMI on all combinations of equipment I have tested and this was before I had read anything about jitter. I have never tested glass vs plastic Toslink and was using plastic Toslink cable when testing.

read the story by Amir Majidimehr in Widescreen Review, a couple of issues back, he is one of the smartest and most respected men in the industry, and he is already a millionaire, so its not like he's trying to hawk magazines. if you still think digital is a bunch of 1's and 0's, and you can PROVE that you are a smarter man than Mr Majidimehr, than i will believe you, but to MY ears, i HAVE heard a difference, and seeing thats it my stereo/home theater. i will take what all of you wannabe engineers have to say with a BIG grain of salt.

Oy.

Amir participates in these forums (username: amirm). He is well-loved.

BTW, do you need some crow with that salt?