DTS - optical or coaxial?

[tylerdurden]

i want to link my dvd player to my surround sound system which has dts. What is the best way to connect - optical cable or a coaxial cable? I thought optical was the best connection but apparently What Hifi have tested them both and found coaxial sounds better.

ta

[yoda313]

Personally I find both are about the same. I had a sony dvd player with a optical out and used that for awhile. Now the dvd player I'm using only has coaxial out and it sounds just about the same.

I'd say it doesn't really matter pesonally. The best thing is whatever works for you. If you have both types of outputs on your dvd player and both types of inputs on your receiver just do a comparison on your own.

[Krispy Kritter]

As far as connectivity goes, they are equal. The differnce would be in the dvd player itself, the cables, or the receiver.

As yoda313 suggested, try them both and see what works best for you.

[BJ_M]

i would give a slight edge to optical , though they tend to fall out

[louthewiz]

They are both the same signal wise there is no audible difference at all.

[davideck]

One advantage of optical is that it is electrically isolated. This prevents a potential ground loop which can sometimes introduce hum into the system.

[edDV]

One advantage of optical is that it is electrically isolated. This prevents a potential ground loop which can sometimes introduce hum into the system.

Yes and optical may be the better choice for long cable runs. Long run coax cable needs to be better quality and may need equalization if very long. Usually ground loop problems correlate to long cable runs anyway.

For short distances (under 25ft), performance is about equal.

[BJ_M]

ground loop problems can happen on lenth of cable , even 1 inch ....


digtial coax is supposed to be 110 ohms impeadance, though most is 75ohms , not really a major issue in consumeer equipment ...

[SingSing]

Ground loop is an analog only problem, it does not affect digital signal.

[Nelson37]

Reviews I have read seem to indicate that this is one of those areas where theory does not always translate into the real world.

Just like some units that show better quality video thru composite, when S-video should be better, it comes down to the quality of components used in the particular hardware you happen to have.

Theoretically, aside from electrical issues, they should be the same. In the real world, with actual testing, they most definitely are not, at least not always. Some units had better coax, some had better optical.

So it comes down to testing your particular setup and deciding for yourself. But remember to retest if you change either your input or output device, this changes the equation.

[BJ_M]

Ground loop is an analog only problem, it does not affect digital signal.

a ground loop can add a hum to your system even when switched to a digital input i assure you .... it doesnt always happen , but happens enough ....

[SingSing]

Don't worried. That's not a type of mistake that engineers will made. Digital ground is always decoupled from the analog ground.

[BJ_M]

on consumer equipment - the shield is electrically the same as the shield on the analog .... test it out

[edDV]

ground loop problems can happen on lenth of cable , even 1 inch ....


digtial coax is supposed to be 110 ohms impeadance, though most is 75ohms , not really a major issue in consumeer equipment ...

True but it usually happens room to room or circuit breaker to circuit breaker using different ground points. As people start to move audio/video around a house room to room, these issues become prominent. This problem is often worse in house wiring vs. office wiring.
http://www.elect-spec.com/faqgrdl.htm

Ground loop is an analog only problem, it does not affect digital signal.

Not always true but if an audio coax creates a hum loop in your S-video or in your audio amp output, is this not a problem? Are you happy because the AC-3 decoder still works?

[chesterfield]

both are equal in terms of sound quality if the proper cables are used. i bought a panasonic 5 disc changer last year and was amazed that there was no optical output...but...the coax signal is just as good....

[SingSing]

on consumer equipment - the shield is electrically the same as the shield on the analog .... test it out

Digital audio is a mixed signal system, that always need seperate digital and analog ground.

Analog ground and digital ground merge into system ground (which can be chasis/shield ground) via inductors and common mode chokes. These are well understood by designers. These circuits have very very low Dc resistance, and measured like shorts on an ohm meter.

If the receiver can't do this right, then it should have a lot of other problems. It should not able get thru production floor, which actually has many kinds of ground issue, and operate by unskilled ( known as off the street ) labor.

[BJ_M]

SingSing, i designed/install millions of $$ worth of equipment into studios and every other type of venue you can think of -- ive ive seen plenty of ground loop problems on both Digital and Analog and mixed systems .. and this is on some of the best equipment in the world .... it most often happens when good grounding practise is not followed by either the designers or the installers before im there....