If you are building a home studio you’ll have to deal with cables. Not a very sexy subject but you’ll have to deal with them like it or not.
Not knowing much about cables can not only be confusing but can lead to a lot of “WTF?!” moments and can also leave you exposed to companies that will try to rip you off.
We’ll look at some of the most common types of cables you’ll find in a typical studio and how they work.
At the end of this, you’ll be better prepared to set up your home studio and even take some equipment decisions, hopefully before you get out to buy stuff.
Balanced vs unbalanced cables
On most professional audio equipment you’ll notice the inputs and outputs being labeled as balanced, unbalanced or bal./unbal. But what does that even mean?
Well, let’s start with from the typical headphone cable. You plug the jack into your phone and you hear the music in two separate speakers, left and right. That is a ‘normal’ stereo cable.
That stereo cable is made out of two mono cables bundled together, one for the left channel and one for the right channel. This, in practice, means that a source sends a signal to a speaker and that is it.
The problem is that your cable acts like an antenna and picks up noise due to electromagnetic interference from other electronic devices.
It’s not too much of an issue for short cables if there is nothing around them but the longer the cable, the more problems you have.
The same with electronic devices or other cables around your cable. The more electronic ‘stuff’ you have, around your cables, the more noise they are going to pick up.
So far we talked about unbalanced cables. Balanced systems come in to solve the above-mentioned problems.
Notice that I called them systems.
That is because the cables are only a part of the system and in order for this to work, you need the full system.
So, the whole system includes a transmitter, cable, and receiver. For example, a microphone records your voice and transmits the signal through a cable to your sound card, the receiver. Or your audio interface sends a signal to your studio monitors.
All of these devices make a balanced system if they are equipped to be part of it. Your microphone will send a balanced signal, through a balanced cable and has to be received by a, also balanced, device.
If any of those components is not equipped to be part of a balanced system, the thing doesn’t work and will not solve the problems mentioned earlier.
For instance, most studio monitors accept balanced input but not all audio interfaces send a balanced signal. You may have balanced cables but you don’t get a balanced signal.
I’m stressing this because if you don’t pay attention you might be thinking you have a balanced system when in fact you might not.
By the way, this is part of the reason you might want an audio interface for your studio monitors.
I noticed that a lot of people just plug them into their computers directly but that can cause quite a bit of noise.
Not only you are directly connecting to a big electronic device, you probably also have a mess of cables behind your computer from which to pick up noise.
With an audio interface that sends a balanced signal, that would not be an issue.
How do balanced cables work
So, now that we got that out of the way, let’s talks about how these systems work and why you actually need all of these components to be balanced.
We mentioned earlier that with a ‘normal’, mono cable you get one signal. You pair two of these and you make a stereo cable.
With a balanced signal, a cable carries two signals but it’s still mono.
What the sender does, it duplicates the signal and the copy is phase inverted to 180 degrees. The signals become completely opposite.
When you put them together, they cancel each other and you hear nothing.
Now, as the signals travel through the cable, they both pick up the same about of noise, in the same phase.
Now you probably guess what is going to happen. At the receiver, you invert the phase of one signal to 180 degrees so the noise on both signals become out of phase with each other.
At this point, you have two ‘music’ signals in the same phase and two noise signals in opposite phase.
Now you combine the two signals. The noise will cancel itself and you are left with your ‘music’ signal intact.
And you might be wondering, well, now I have two audio signals on top of each other so the signal should also get stronger, right?
Yep, on short runs, you could say that you get a bit of a boost. On longer runs, the signal loses strength as the cable gets longer and longer anyway.
Balanced connectors and cables
Most commonly, you’ll use XLR and/or TRS for balanced connections. All other types of connectors, you can assume they are not balanced unless otherwise specified in their documentation.
However, I have to stress this, read the manual for the gear you are using to make sure they send/receive balanced signals and with what inputs/outputs.
You’ll find XLR and/or TRS on pretty much everything that has anything to do with audio, interfaces, monitors, mixers, processors, microphones, and so on.
Also, TRS and TS are two different animals, make sure you don’t confuse the two. TRS is balanced but TS is not. They may look very similar at a quick glance but internally they are not.
Are balanced cables the same as stereo cables?
Technically, yes. But…
Here is the thing with these, they can carry stereo signals that are unbalanced. OR they can carry a mono signal that is balanced.
It depends on what you connect the cable to. If you add it to a balanced output, it will carry a balanced mono signal.
What happens if I use an unbalanced cable in a balanced input/output? What if I use a balanced cable in an unbalanced input/output?
Most likely, nothing. You’ll get a regular, unbalanced signal.
Like previously mentioned, you need all the pieces to be balanced in order to get a balanced connection.
Other studio cables and what they are used for
So, we focused mainly on balanced/unbalanced cables so far and that is because of those, I think, are the most important to get right to eliminate confusion and some of the noise in your system.
But, of course, there are also other cables that you’ll likely encounter and you might want to know what they are good for and when to use them.
You know this guy. It’s everywhere, but don’t skip it.
You’ll find USB for a lot of things these days, MIDI keyboards, audio interfaces, some microphones even.
Here’s what happened to me and it took a while to figure out. I had noise coming out of my monitors even though I had an audio interface sending balanced signals to the monitors and everything should have been balanced. It was balanced.
After a lot of digging and trying to figure out ‘what the heck’ I checked the USB cable from the computer to my audio interface.
The cable was picking up noise from the mess of cables behind my computer so the audio interface was adding that as part of the regular signal, bypassing the whole balanced system.
The reason for all this mess was that my USB cable didn’t have any protection. And what I mean by that are those ferrite beads you see on, mostly, all cables.
I switched the USB cable to one that had ferrite beads and the issues were gone.
So, yeah, check your audio interface USB cable if nothing else makes sense.
They look very similar to TRS but they are mono and they are not balanced. Notice the extra ring on the TRS, this helps you easily identify which is TS and TRS.
These cables are commonly used with electric guitars
You’ve probably seen this guy on some audio/video devices. The connector itself doesn’t have any advantage over other connections and it can’t carry balanced signal.
This is a connector that you’ll see on MIDI devices. This is not an audio cable though.
MIDI devices send and receive instructions rather than audio. Those instructions can be used by the receiving device to do something with them.
For instance, sending MIDI from a keyboard to a synthesizer, the latter will know what notes to play but it will do so with its own sounds.
There are, of course, a lot more cables and connectors in the world of audio but these would be the most common a small bedroom studio will host.
Hopefully, now you know more about what balanced cables and how to make sure your system is balanced, as that is a very important part of your studio setup.