digital stereo question

[jungle]

i wasn't sure where to ask this one...

i have been using the digital output on my diamond mx300 sound card piped into my reciever. has anyone ever tried to put a "y-adaptor" on there to pipe it out to two recievers? further more is there a difference between your standard ho-hum rca cables and ones made for digital stereos?

 

[sohcrates]

I've personally never used a y-adapter on a digital out, but i see no real reason why it shouldn't work

as far as differences between cables, digital is digital...as long as the peaks of the signal are getting through, it's fine.

My only real cable advice is that if it's a relatively long run, use a slightly thicker cable (something like radio shacks gold series).

I've used several different RCA cables on my digital out and have never noticed a difference.

 

[Superdoopercooper]

digital is digital. As long as your receiver gets the 1's and 0's uncorrupted (meaning... if a $3 cable works fine and a $200 cable works fine --> use the $3 model)... the music will be OK.

Splitting it should be ok, as long as both recievers combined don't load the output of the sound card down to much. Just experiment... you really won't risk hurting anything (if all was designed properly).

 

[ArbitrarilyInsane]

I have a slightly different question along the same lines. What about splitting a signal coming from an lnb on a sattelite dish. Everyone I ask, says I need a second lnb for it to work. Thats too much hassle. Do you think I can split the same satellite signal to two wires to seperate Digital Satellite recievers?

 

[ScottMac]

N O, you cannot use a single LNB to drive more than one receiver. THe receiver puts out a +13VDC and +18VDC signal to switch between the two polorizations available from the satellite.

If you put a splitter on the line, the two switching voltages from the two receivers will conflict. You may burn out the receivers. It's a BAD THING.

Dual LNBs are not that expensive. Buy one and drag in another cable. If you need to feed more than two receivers, then get a multiswitch. These are your least expensive/least hassle solutions. Buy good quality cable, make sure the connections are well terminated and sealed against the environment.

Good Luck

Scott

 

[spidey07]

Great,

two audiophiles in a highly technical discussion.

Splitting digital connections on coax = bad idea like ScottMAC suggested. Splitting optical cables given the consumer crap they call fiber would result in too much loss.

Yes, there is a big difference between run of the mill RCA cables and 75 ohm coax used for digital connections. Try both and let your ears decide.

OH, btw. Yes most cable manufactures charge extra for the "digital" word on the packaging even though it is exactly the same model as their "super premium, $100 video cable." And don't get me started on optical cables that say "Gold plated for superior sound!"

<---EE and audiophile, I argue with myself everyday. Lets talk jitter and speed of light.

 

[ScottMac]

I was specifically addressing the question about splitting the Digital Satellite signal from a single LNB. I don't know why he doesn't believe "Everybody"...and he probably won't believe me....maybe after he smokes his IRD/receiver...(or trashes his bootleg card).

I have semi-expensive cables on my video feeds, pretty decent cables on my audio feeds, and any ol' cheap TOSLINK *cought* fiber on the digital side. Copper digital works OK too...got some of that in there for the old LaserDisk player.

My favorite is the guy cutting the cables to *exactly* the same length...like a trashy-ass human ear could discriminate phase differences of a dozen feet out of a signal that's over twenty miles long. That's the cool part about selling to smart people, they're so gullable and easy to trick......

Spidey: You gotta use the Gold-Clad fiber, or it doesn't make good optical contact when you punch it down.

 

[Superdoopercooper]

<< Great, two audiophiles in a highly technical discussion. Splitting digital connections on coax = bad idea like ScottMAC suggested. Splitting optical cables given the consumer crap they call fiber would result in too much loss. Yes, there is a big difference between run of the mill RCA cables and 75 ohm coax used for digital connections. Try both and let your ears decide. OH, btw. Yes most cable manufactures charge extra for the "digital" word on the packaging even though it is exactly the same model as their "super premium, $100 video cable." And don't get me started on optical cables that say "Gold plated for superior sound!" <---EE and audiophile, I argue with myself everyday. Lets talk jitter and speed of light. >>



Dude... I'm an EE, an audio enthusiast (more of a videophile), a test engineer, and I did my master's thesis on the electrical characteristics of audio RCA cables. I disagree with you, but that is fine. The following is my rant... please take no offense Spidey... this is my general rant against anyone who claims that distinct sound improvements is in the cable (NOTE: I think if this guy has a $2k CD transport and a $5k Lexicon process, and $5k Dreadnaught amp, then I would more believe your claim about the cable being a limiting factor.... but with a Diamond soundcard and probably some mainstream receivers... I think the "less that good sound" is more due to all the electronics and not this passive cable issue).

Therefore, it was my conclusion that high dollar doesnt always equal high quality/improved sound. MOREOVER, he is talking about the Digital COAX line for the audio.... let's see here.... a logic level of 0V is a zero... a logic level of 3.3 or 5V is a ONE. As long as your receiver (dig decoder) is getting a 0 and a 1 distinctly... it will be converted correctly downstream. I'm sorry, but if you think a better cable is going to make a digital one and zero sound better, then you must be one of those rich guys who can afford gimmicks and hype (no offense here.... but this really sore spot with me... so many consumers getting duped). I'll agree that if it was an analog output... then the cables may have some audible difference.... but not for carrying a low bit-rate digital signal... esp. over a cable run that is probably 1 or two feet. You must have some bionic ears. I suggest you quit whatevver job you're doing and go work for Sony, Denon, any speaker company, etc. You'd be the KING... and rich too.

Give me some data that shows the better cables will make the system sound better (i.e... some measurements showing a more accurate frequency response/phase/whatever/etc.) and I'll listen with open ears. I think psycho-acoustics come into play here --> "I spent $35 on this cable... therefore it MUST sound better".

<end rant>

I thought about deleting this^^^.... but I bet it will get an interesting discussion going. hehehehehe... (can't we all just get along )

 

[ArbitrarilyInsane]

[Plenty of head scratching later] Woah! thats a lot of money for entertainment. My entire Audiovideo system definitely costs less than £2500 including tv, video, dvd, Sky Digital Satellite system, DD5.1/DTS Surround kit AND a computer. Convert that to dollers and its probably less than $4000. and I aint complainin'.

Anyway thanks to those who helped, ignoring anyone trying to take the mickey. Its just that I didn't trust the other people who told me to get another lnb because they were one the other and of the phone and are called salespeople. And since I have a spare satellite decoder and some cable (I actually have a spare dish with an lnb, too much hassle to put it up), i thought lets try splitting the cable. Well, now that sounds like not such a good idea.

Thanx again.


ps. If i had ears like that, I'd apply at Dolby labs or Industrial Light and magics THX department.

 

[spidey07]

sooperdoopercooper,

hehehe, no offense at all. You're agreeing with me.



<< Give me some data that shows the better cables will make the system sound better >>


Hit the nail on the head there.


<< no offense here.... but this really sore spot with me... so many consumers getting duped >>


yes, yes they are.

This whole consumer *cough* fiber cable stuff have my panties in a bunch as well. I'm trying to get a hold of some TOSLINK connectors so I can make my own REAL fiber optic cable (use some AMP or siecor stuff). The whole "well coax sounds better than TOSLINK" makes no sense to people like scott and I (and probably you) who happen to have worked on digital transmission for 10 years.

You can split a fiber cable into two stands to but you'll incur some loss. As long as that dB loss is in your budget then split that sucker!

heh, lexicon processor I wish. simple krell blocks and Thiel cs2.3 for me.

ps - what was your conclusion on RCA cables? I'm very interested.

 

[Superdoopercooper]

Spidey... oh... when I was ranting... I was talking about COPPER cables. I know very little about optical.. but I still can't ever believe the "Toslink sounds better than the other thing" argument. Splitting optical is a whole different bag o' worms... I guess.

Anywyas... about my thesis... I used to have a nice WORD document... but in a Zip Drive to CD-R burn SNAFU, I lost it. I may have it on a floppy somewheres... but in any case, I have a hard copy... maybe I'll "PDF" it. Due to budgetary limitations (mine)... I was only able to compare a cheap "out of the CD player box" RCA cable, a top o-the line RS gold plated model... and then about 9 different models that Monster cable was nice enough to send me for evaluation.

My conclusion: the low end Monster (M400 if I remember right) and the $10 radio shack job had the best electrical characteristics... beating out the $99 MC's that I tested. A note though.... All cables came to within a dB or so of each other. Ridiculous. I wanted to do a double blind listening test with all those cables, but time just didn't permit it.

I used an audio precision box to do the testing... as well as a hugh O-matic HP impedance measurement monster thing. SO, I did a frequency sweep type of comparison, and also a lumped parameter circuit analysis type comparison.

I sent the thesis to Monster when I was done. Needless to say... never heard anything back. Wonder why?? They just keep the marketing machine going and keep duping the dumb-0 customers.

Oh... and yes... I'll take the KRELL blocks and the Theil 2.3c's. Heck... give me a Denon 3802 and some Monitor Audio Silver or Gold cinema series speakers and I'll be in heaven. All I got now is a Sony STR-DB830 and some Infinity SM series speaks. As soon as I win the lottery or inherit a gillion dollars... I'll be all over that high end stuff.

 

[jungle]

ANSWERS!!!

i finally had some time to play w/ it! this is what i found:
from a diamond mx300 to a gold plated y-adaptor into gold plated rca cables (that i had left from a car amp install) into both a nice sony reciever and a hohum awia reciever.

i get sound out of both recievers!!!!! so the answer is yes you can use y-adaptors!!! however (there had to be a catch) i hear like a static clicking (ever so faint, but anoying) out of the awia. I swapped cables and a bunch of stuff, but the static remains. I dunno if it has to do w/ the quality of the y-adaptor or the quality of the awia reciver or what. Come to think of it i can remember if i tried the awia all by itself w/o the y-adaptor.

 

[Packy]

I've been splitting the digital coax-out of my SBLive for a long time, and it works wonderfully. One cable runs to my digital Altec Lansing THX'ers, and the other runs for almost 50' out to the receiver in my living room. The sound quality difference from splitting or not splitting is unrecognizable, at least to me Along with the digital audio, I also have svideo running to the receiver, so it's great for watching South Park or whatever, and listening to MP3s while watching winamp visualization plugins

I guess that's another question though... does distance affect digital signals significantly? I tried to read all the posts in this thread, but I may have missed the answer to my question already.

 

[Zaphs]

To ArbitrarilyInsane:
ScottMac is correct in saying that two receivers would blow your LNB, but, all you need to do is purchase either a DCBlock barrel or a splitter that covers the L-Band and has one leg DCBlocked. We use them all the time at work, I have upto 20 IRD's/IRT's hooked up to the same LNB feed (admittedly it's coming from a 7 meter Simulsat Dish but the theory is sound).

The DCBlock barrel looks just like a normal F-Barrel. Go to your local Radio supply store.

 

[Yoshi]

Never tried the y adapter, but I don't see why it would not work.

As far as the cables, ho-hum cables will work. The made for digital cables have a different impedence per the SPDIF standard and will have much better signal transfer over longer distances. I think longer is defined as over 6 feet, it has been a while since I read up it.