SB Live 5.1 unbalanced line level outputs

blitter2 · Jun 29, 2011, 07:55 PM

Can I use coaxial cable for kx project sound ouput of a Live 5.1 card?

Or the impendence and capacitance of the coaxial cable can ruin my pci card?

Tyrsonswood · Jun 29, 2011, 08:15 PM

The cable is fine for line level signals produced by the card. Just make sure you are matching stereo and mono correctly. "Coax" by name is usually mono.

Also, huge cable (diameter) and long cable runs can degrade the sound.

blitter2 · Jun 29, 2011, 08:21 PM

Thank you a lot Tyrsonswood.

blitter2 · Jul 12, 2011, 08:30 PM

Please could I use cat5 utp cable for outputing or inputing with Live 5.1 and soundcards in general?

I am asking because cat5 utp cable's construction is similar to "Balanced" audio cables and it has been said that Live 5.1 has unbalanced line level outputs and perhaps input.

I want to do it for noise rejection, not to have a balanced audio system running. Or will I?

Can it be dangerous for my pci card?

Russ · Jul 12, 2011, 09:16 PM

Take a look at:
Balanced vs. Unbalanced Interconnects — Reviews and News from Audioholics
Balanced Vs. Unbalanced Cables (What’s the Difference?) | ObiAudio

The stereo jacks of the sound card have only 3 conductors, signal for left, signal for right, and a shared ground (balanced would have 3 conductors per channel).

blitter2 · Jul 12, 2011, 09:20 PM

Russ I have soldered only 2 conductors (of utp's 8 in total) at each end. Signal for left and right.

Same twist's ones. Brown and Brown-White and the same at the opposite end.

But nothing for ground (I forgot). I can add it though.

From what I understand this is not considered a balanced audio cable, because of the less cables in use. But can it be on its unique way dangerous if used with unbalanced line level input-output soundcards?

Because of the 2 signal cables (left and right) are on twist along the full cable length?

I have used unshielded cat5 utp cable.

Russ · Jul 12, 2011, 10:46 PM

I do not think there is any danger using Cat5 cable, but why are you doing this, are you having noise problems?
Having no shield at all could make it even noisier...

Tyrsonswood · Jul 12, 2011, 10:48 PM

If right and left are twisted like that you may get crosstalk between the two channels. Better to have left twisted with a ground and right twisted with a ground. In other words the two channels have their own twisted pair of signal and ground. Still not ideal but a better plan if you must use cat5.

blitter2 · Jul 12, 2011, 11:01 PM

Thank you Tyrsonswood.

Tyrsonswood · Jul 13, 2011, 02:52 AM

By using a twisted pair, hot and ground, you are almost running a shielded cable... It's just not 100% shielded.

blitter2 · Jul 13, 2011, 06:30 PM

Yeah Tyrsonswood.

Please in your opinion what can be a better kind of utp cable to use, single-core utp or multi-core utp?

Please would it output sound with ground not connected? I am asking because I am new at soldering and I would like to do trial and error.

Russ · Jul 13, 2011, 07:59 PM

Quote:

Originally Posted by Tyrsonswood

By using a twisted pair, hot and ground, you are almost running a shielded cable... It's just not 100% shielded.

Of course, but I am not sure what the advantage is of using CAT5 cable like this. When used with an unbalanced signal source, you lose a lot of the advantages that CAT5/twsited pair would otherwise give you.

blitter2 · Jul 13, 2011, 08:06 PM

Russ, the advantage could be (if it works), that CAT5 perhaps could be used as a semi-shielded cable ,avoiding the big impendence and shield capacitance of coaxial cable.

Tyrsonswood · Jul 13, 2011, 08:35 PM

How long are you running these cables? Some of the things you're talking about only matters when making extremely long cables..... like several hundred feet. I would just use coax and be done with it if it were me.

To answer one question, you need both hot and ground to get sound. If you do get sound by just connecting the hot then ground is coming from shared electrical grounding (the AC power source GND) this usually is not safe and may introduce noise.

blitter2 · Jul 13, 2011, 08:41 PM

1,5 meters.

Thank you Tyrsonswood and Russ.

blitter2 · Jul 19, 2011, 11:05 PM

Tysronswood, I have constructed a mono cable for subwoofer use with hot and ground and it sounds good.

I have as well constructed another one, with left and right channel, but no ground cable. And sound works. For both channels.

Please about ground coming from shared electrical grounding, does the fault has to be from my own appartment, or it can be from another appartment of this building?

Please how does this fault happens electrically?

Please is there any measures I can take? Is it dangerous for my pc and electronics?

Btw it doesn't introduce any noise at all with kx project Line-In. Line-in noise just reaches -72db using ProFX ADC and Live 5.1 with nothing connected at the jack input of Live 5.1 . I think it is normal.

Tyrsonswood · Jul 20, 2011, 12:41 AM

Sounds like the noise levels are fine, I'd still use a ground wire if possible. Being an old guitar tech/sound tech I've seen too many "bad ground" issues. I just always think "ground is more important".... it's kind of my mantra. If the hot isn't correct, no sound.... if ground isn't correct it could do anything. (not in the case of your system, but in live stage setups, improper grounding can, and has, killed. So I tend to make it a priority) Proper grounding is also vitally important in guitar building, and effects pedal setups, which was my main focus....... Noise introduction was usually ground related, either missing or improperly done.

If you want to check your setup, turn on a florescent light somewhere close by..... that will let you know in a hurry as you will hear it.

Is the reason for not doing a ground with the right and left channel just because of the type of wire you are using?

blitter2 · Jul 20, 2011, 09:24 AM

No.

I had just completely forgot about ground wire for that cable.

I am anyway not using that cable anymore.

"but in live stage setups, improper grounding can, and has, killed"

What did you ment? Ruined equipment?

Florescent light. LP lamp. What would I have to realize with this test?
If I hear interfierence from the lamp then ground for the audio cable was not properly done ?

Or if the amp is properly grouded via power cord, can't be affected from the florescent light?

I have moved a florescent light close to a portable stereo (utilizes no ground pin on its power cord) with no line-in cable connected and I could hear the interference.

Tyrsonswood · Jul 20, 2011, 12:11 PM

Quote:

"but in live stage setups, improper grounding can, and has, killed"

What did you ment? Ruined equipment?

Ruined equipment can be replaced...... Improper grounding has killed musicians, roadies, and techs. Again, this wouldn't happen with your setup, but there would be an outside chance of equipment failure. Remote, but possible. The reason your cable worked without a ground is because your computer and amp were on the same power outlet. Problems come into play when equipment are on different outlets and it would depend on how the house was wired. There could be a voltage potential (here in the US it would be 120 volts) between two different outlets. I've only mentioned this because it's the reason I think ground is more important than most people think.

I mentioned the florescent lamp because they are the worst noise generators imaginable. You can't always remove all the noise, but they can also point out problems that can be fixed. What you heard on the portable stereo is exactly what you would hear. Without a grounded shield wire on an audio cable this noise can enter the audio signal. This type of noise is what a good coax cable is designed to reject.

So, you have changed the cable and all is good now?

blitter2 · Jul 20, 2011, 12:20 PM

Yes I have changed it. All good now.
Thank you Tyrsonswood.

Please Tyrsonswood, is same power outlet for amp and computer good for sound outputing from the computer via the amp?
Or different power outlets can be better?

My amp doesn't utilizes ground for any ground-loop to happen from shielded audio cables.

Tyrsonswood · Jul 20, 2011, 12:49 PM

You should be on the same outlet with all your equipment if possible.

blitter2 · Jul 20, 2011, 01:02 PM

Thank you very much Tyrsonswood.

Tyrsonswood, if I place my florescent light onto my desk close to my tft monitor do you please know if the light can negatively effect the monitor as it does on amps?

Tyrsonswood · Jul 20, 2011, 01:29 PM

That I don't know but I would suspect not....... Monitors should be shielded and running at totally different frequencies. It is generally not a good idea to use florescent lighting near sound equipment, but if it's not causing any noise problems it's not hurting anything.

blitter2 · Jul 20, 2011, 01:43 PM

Thank you Tyrsonswood.

blitter2 · Jul 21, 2011, 12:31 PM

Tyrsonswood, please if I use coax cable and it only gets grounded at the computer end, would the shielding 100% work?

My amp doesn't utilizes ground.

Tyrsonswood · Jul 21, 2011, 01:39 PM

It would still shield, yes. Not sure what you mean by your amp not utilizing ground though. The line level inputs, lets just say for the right channel for now, has a hot wire and a shield/GND/negitive/whatever..... that IS ground. Left channel would be the same. Just because a piece of equipment does or doesn't have a 3rd lug on the power cord, this doesn't mean it's shielding or not shielding it's inputs. Both are "ground" but we are talking about it on different level here.

blitter2 · Jul 22, 2011, 07:32 PM

Thanks Tyrsonswood.

Tyrsonswood, please can an surge protector power bar with EMI-RFI filter, make an amp be feeding larger current to a speaker than it usually does when connected straight to the wall socket?

From what I have read these devices have an 0.4 ohm DC filter which makes DC resistance bigger for devices conncted to it.

When the added DC resistance, will an amp be feeding an equally larger current to the speakers?

Tyrsonswood · Jul 22, 2011, 08:24 PM

I wouldn't think so, at least not with a well designed amp and speaker combination. A .4 ohm filter before an amp doesn't add .4 ohms to a speakers rating if that is what you are getting at. Everything I own runs off of some kind of filter or filter/isolation transformer combination, and I've never noted any problems.

blitter2 · Jul 22, 2011, 09:06 PM

Tyrsonswood Thank you.

Isolation transformer, interesting.

Do you use an AC power one or an audio specific one?

Tyrsonswood · Jul 22, 2011, 09:19 PM

Tripplite.... I have the 1800 watt version of these, 4 of them actually.

LCR2400 - Line Conditioner - Automatic voltage regulation with surge protection

Jun 29, 2011, 07:55 PM	#1
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	SB Live 5.1 unbalanced line level outputs Can I use coaxial cable for kx project sound ouput of a Live 5.1 card? Or the impendence and capacitance of the coaxial cable can ruin my pci card?

Jun 29, 2011, 08:21 PM	Thread Starter #3
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	Re: SB Live 5.1 unbalanced line level outputs Thank you a lot Tyrsonswood.

Jul 12, 2011, 08:30 PM	Thread Starter #4
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	Re: SB Live 5.1 unbalanced line level outputs Please could I use cat5 utp cable for outputing or inputing with Live 5.1 and soundcards in general? I am asking because cat5 utp cable's construction is similar to "Balanced" audio cables and it has been said that Live 5.1 has unbalanced line level outputs and perhaps input. I want to do it for noise rejection, not to have a balanced audio system running. Or will I? Can it be dangerous for my pci card? Last edited by blitter2; Jul 12, 2011 at 08:43 PM.

Jul 12, 2011, 09:16 PM	#5
Russ HardwareHeaven Extreme Member Join Date: Jan 2005 Posts: 5,563 Rep Power: 62	Re: SB Live 5.1 unbalanced line level outputs Take a look at: Balanced vs. Unbalanced Interconnects — Reviews and News from Audioholics Balanced Vs. Unbalanced Cables (What’s the Difference?) \| ObiAudio The stereo jacks of the sound card have only 3 conductors, signal for left, signal for right, and a shared ground (balanced would have 3 conductors per channel). Last edited by Russ; Jul 12, 2011 at 09:22 PM.

Jul 12, 2011, 09:20 PM	Thread Starter #6
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	Re: SB Live 5.1 unbalanced line level outputs Russ I have soldered only 2 conductors (of utp's 8 in total) at each end. Signal for left and right. Same twist's ones. Brown and Brown-White and the same at the opposite end. But nothing for ground (I forgot). I can add it though. From what I understand this is not considered a balanced audio cable, because of the less cables in use. But can it be on its unique way dangerous if used with unbalanced line level input-output soundcards? Because of the 2 signal cables (left and right) are on twist along the full cable length? I have used unshielded cat5 utp cable. Last edited by blitter2; Jul 12, 2011 at 09:50 PM.

Jul 12, 2011, 10:46 PM	#7
Russ HardwareHeaven Extreme Member Join Date: Jan 2005 Posts: 5,563 Rep Power: 62	Re: SB Live 5.1 unbalanced line level outputs I do not think there is any danger using Cat5 cable, but why are you doing this, are you having noise problems? Having no shield at all could make it even noisier...

Jul 12, 2011, 11:01 PM	Thread Starter #9
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	Re: SB Live 5.1 unbalanced line level outputs Thank you Tyrsonswood. Last edited by blitter2; Jul 13, 2011 at 12:15 AM.

Jul 13, 2011, 06:30 PM	Thread Starter #11
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	Re: SB Live 5.1 unbalanced line level outputs Yeah Tyrsonswood. Please in your opinion what can be a better kind of utp cable to use, single-core utp or multi-core utp? Please would it output sound with ground not connected? I am asking because I am new at soldering and I would like to do trial and error. Last edited by blitter2; Jul 13, 2011 at 06:37 PM.

Jul 13, 2011, 08:06 PM	Thread Starter #13
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	Re: SB Live 5.1 unbalanced line level outputs Russ, the advantage could be (if it works), that CAT5 perhaps could be used as a semi-shielded cable ,avoiding the big impendence and shield capacitance of coaxial cable. Last edited by blitter2; Jul 13, 2011 at 08:45 PM.

Jul 13, 2011, 08:41 PM	Thread Starter #15
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	Re: SB Live 5.1 unbalanced line level outputs 1,5 meters. Thank you Tyrsonswood and Russ. Last edited by blitter2; Jul 14, 2011 at 02:49 PM.

Jul 19, 2011, 11:05 PM	Thread Starter #16
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	Re: SB Live 5.1 unbalanced line level outputs Tysronswood, I have constructed a mono cable for subwoofer use with hot and ground and it sounds good. I have as well constructed another one, with left and right channel, but no ground cable. And sound works. For both channels. Please about ground coming from shared electrical grounding, does the fault has to be from my own appartment, or it can be from another appartment of this building? Please how does this fault happens electrically? Please is there any measures I can take? Is it dangerous for my pc and electronics? Btw it doesn't introduce any noise at all with kx project Line-In. Line-in noise just reaches -72db using ProFX ADC and Live 5.1 with nothing connected at the jack input of Live 5.1 . I think it is normal. Last edited by blitter2; Jul 19, 2011 at 11:44 PM.

Jul 20, 2011, 09:24 AM	Thread Starter #18
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	Re: SB Live 5.1 unbalanced line level outputs No. I had just completely forgot about ground wire for that cable. I am anyway not using that cable anymore. "but in live stage setups, improper grounding can, and has, killed" What did you ment? Ruined equipment? Florescent light. LP lamp. What would I have to realize with this test? If I hear interfierence from the lamp then ground for the audio cable was not properly done ? Or if the amp is properly grouded via power cord, can't be affected from the florescent light? I have moved a florescent light close to a portable stereo (utilizes no ground pin on its power cord) with no line-in cable connected and I could hear the interference. Last edited by blitter2; Jul 20, 2011 at 11:16 AM.

Jul 20, 2011, 12:20 PM	Thread Starter #20
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	Re: SB Live 5.1 unbalanced line level outputs Yes I have changed it. All good now. Thank you Tyrsonswood. Please Tyrsonswood, is same power outlet for amp and computer good for sound outputing from the computer via the amp? Or different power outlets can be better? My amp doesn't utilizes ground for any ground-loop to happen from shielded audio cables. Last edited by blitter2; Jul 20, 2011 at 12:43 PM.

Jul 20, 2011, 01:02 PM	Thread Starter #22
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	Re: SB Live 5.1 unbalanced line level outputs Thank you very much Tyrsonswood. Tyrsonswood, if I place my florescent light onto my desk close to my tft monitor do you please know if the light can negatively effect the monitor as it does on amps? Last edited by blitter2; Jul 20, 2011 at 01:11 PM.

Jul 20, 2011, 01:43 PM	Thread Starter #24
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	Re: SB Live 5.1 unbalanced line level outputs Thank you Tyrsonswood.

Jul 21, 2011, 12:31 PM	Thread Starter #25
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	Re: SB Live 5.1 unbalanced line level outputs Tyrsonswood, please if I use coax cable and it only gets grounded at the computer end, would the shielding 100% work? My amp doesn't utilizes ground.

Jul 22, 2011, 07:32 PM	Thread Starter #27
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	Re: SB Live 5.1 unbalanced line level outputs Thanks Tyrsonswood. Tyrsonswood, please can an surge protector power bar with EMI-RFI filter, make an amp be feeding larger current to a speaker than it usually does when connected straight to the wall socket? From what I have read these devices have an 0.4 ohm DC filter which makes DC resistance bigger for devices conncted to it. When the added DC resistance, will an amp be feeding an equally larger current to the speakers? Last edited by blitter2; Jul 22, 2011 at 08:10 PM.

Jul 22, 2011, 09:06 PM	Thread Starter #29
blitter2 HardwareHeaven Lover Join Date: Sep 2008 Posts: 196 Rep Power: 26	Re: SB Live 5.1 unbalanced line level outputs Tyrsonswood Thank you. Isolation transformer, interesting. Do you use an AC power one or an audio specific one?