The Ins and Outs of Cables

[Chitta]

Hello,
This is my first post.
I'd like a little gentle coaching on different types of cables' functionally.

Things I understand:
TRS stands for Tip Ring Sleeve and is a cable that has a balanced signal.
TS stands for Tip Sleeve and is an unbalanced signal.
XLR is synonymous with "mic cable" and carries a balanced signal.

Line Level inputs usually play well with (keep low noise levels with) "nominal output levels" of +4dB

Instrument inputs ought to have a built in pre amp because "Instruments" Bass and Guitar and Rhodes etc. have a low signal like -30dB or something and we need to boost that shtuff up while keeping the noise down.

Mic Inputs usually also have preamps and additionally often have a +48v option for Condensers (which need phantom power.)

Okay so first, if any of you lovely members of this online community would be so kind, please correct my misconceptions above, and next:
I'll barrage you geniuses with all my newbie questions.

What are the problems in theory with running an unbalanced (TS) cable to a balanced input?

Is there such thing as a balanced input on a mixer/audio interface? Or just balanced outs which go to balanced monitors?

How can I tell the difference between a quarter inch stereo cable and a TRS (don't the both have two bands?) and not just in a store or online but if they are lying at the bottom of a pit twisting in and out of each other Indiana Jones style.

I have a keyboard cable that has arrows for direction on it..... what's the deal there?

Would something bad happen if I ran a strat into an instrument In on a mixer with a TRS cable?


Are there issues for newbs like me that I'm not even addressing here?
(quality of cable aside.)

Please good sirs and madams, offer me your wisdom I'm in a need to know situation.

 

[Chili]

Hello,
This is my first post.
I'd like a little gentle coaching on different types of cables' functionally.

First, welcome to the site.

I'll go ahead and take a stab at some of this. Others might correct me.

What are the problems in theory with running an unbalanced (TS) cable to a balanced input?

Increased noise susceptibility and decreased volume. The balanced cable has the signal going down two wires twisted inside the cable with a shield around it going to ground. The two wires are 180 degrees out of phase with each other so any RF interference would affect both lines at the same time and basically cancel each other out. When you plug an unbalanced line into a balanced jack, you are basically grounding out one of those signal lines. The signal strength is cut in half, plus any benefit from noise cancelling is removed and you will get more noise from RF interfence.

Is there such thing as a balanced input on a mixer/audio interface? Or just balanced outs which go to balanced monitors?

Yes, the XLR inputs are balanced. Also, some might have TRS inouts for the line level stuff. I think most mixers/interfaces these days will have some kind of auto-sensing between balanced and unbalanced signals.

How can I tell the difference between a quarter inch stereo cable and a TRS (don't the both have two bands?) and not just in a store or online but if they are lying at the bottom of a pit twisting in and out of each other Indiana Jones style.

I'm thiking the 1/4" stereo cable is going to be a Y-cable. TRS plug on one end and two TS plugs on the other. A balanced TRS will just have two TRS plugs, one on each end.

I have a keyboard cable that has arrows for direction on it..... what's the deal there?

Wouldn't have a clue. Is it a MIDI cable?

Would something bad happen if I ran a strat into an instrument In on a mixer with a TRS cable?

Try to imagine all life as you know it stopping instantaneously and every molecule in your body exploding at the speed of light. Total protonic reversal. No wait, that's Ghostbusters. Probably nothing will happen. If you use a TRS cable in an unbalanced system, two of the conductors will carry the signal, but in phase with each other. So it's just like having one wire.

Okay, everyone can correct me now.

hth

 

[Chitta]

Thanks so much for the helpful reply!

I'm finding out more stuff with more research.
If anyone is reading this thread with the same questions, try these resources:
http://www.rane.com/note110.html
And
http://www.tweakheadz.com/all_about_cables.htm

 

[Dr. Varney]

Try to imagine all life as you know it stopping instantaneously and every molecule in your body exploding at the speed of light. Total protonic reversal. No wait, that's Ghostbusters. Probably nothing will happen. If you use a TRS cable in an unbalanced system, two of the conductors will carry the signal, but in phase with each other. So it's just like having one wire.

Okay, everyone can correct me now.

hth

Question: Do the molecules explode before or after all life stops?

Dr. V

 

[Chili]

Question: Do the molecules explode before or after all life stops?

Dr. V

Slightly before... there's a fleeting moment when the soul knows what happened.

 

[austinm08]

Question: Do the molecules explode before or after all life stops?

Dr. V

 

[Armistice]

1. Unbalanced cable to balanced input - increased noise susceptibility - yes, but it's only susceptibility - doesn't actually mean there will be increased noise... over a short run, probably no difference at all.

2. Unbalanced cable to balanced input - decreased volume- be willing to be shouted down here, but not that I've noticed - again length of run is probably a factor here.

Why would you be doing this anyway? What are you planning on plugging into what?

3. How can I tell the difference between a quarter inch stereo cable and a TRS (don't the both have two bands?) and not just in a store or online but if they are lying at the bottom of a pit twisting in and out of each other Indiana Jones style.

Stick your hand into the nest of cables/vipers - if you get bitten, it was stereo, if not, it was balanced.... actually, I'm not sure there is one, but someone may know better.. again - do you have one of these cables? Why? What are you using it for? I've never even seen one and never had a use for one.

4. TRS plug on one end and two TS plugs on the other. A balanced TRS will just have two TRS plugs, one on each end. We're talking an insert cable here - Insert cable is TRS and two singles on the other end... a "balanced TRS" (don't think there is such a thing) would need 4 bands on the plug...

5. I have a keyboard cable that has arrows for direction on it..... what's the deal there?

From MONSTER CABLE website:

Why does my instrument cable have arrows?
There are two typical types of cable construction; coaxial and twisted pair. Coaxial construction, as used in our P500 Rock cable, consists of one conductor and the shield. Twisted Pair construction, used in our P500 Jazz and all Studiolink cables, utilizes two conductors and a shield. Connectors such as the RCA type and mono ¼" are considered Unbalanced connectors; due to their two contact surface areas, the tip and the sleeve. (Connectors such as XLR, TRS ¼" (Tip/Ring/Sleeve,) etc. are considered Balanced.) A coaxial cable terminated with an unbalanced connector, uses the conductor as the positive lead, terminated to the Tip, and the shield as the negative lead, terminated to sleeve. Monster Cable makes our Unbalanced cables, "Semi-balanced" by utilizing twisted pair cable. We use one conductor as the positive lead, terminated to the Tip, one conductor as the negative lead, terminated to the sleeve, and we terminate the shield to the Source side of the cable; thereby making the cable directional. The theory goes, if you ground the shield at the Source end and leave it open to "Drain" at the Destination end, any noise or interference which enters the shield, will be kept from making its way into your destination device. Source is considered where the signal is originating from, (think it terms of your signal flow,) Destination is considered the device to which your signal is going.


I think you're worrying too much about this...

 

[dastrick]

TRS cables can be used as either stereo or balanced mono.

Your little 1/8" plug for your headphones is a TRS connection, but it's used to carry a stereo signal.

The balanced AUX OUT from your mixer is a TRS connection, but it's used to carry a balanced mono signal.

 

[Chitta]

Thanks guys. I feel well taken care of.

 

[Armistice]

You're welcome...

Newbies buy the beer...

Dastrick - thanks for clearing up the stereo/balanced mono TRS thing in my head... didn't think there's be a difference... but still don't know what you'd use one for!

Cheers