Everything You Need to Know About Picking Audio Cables
This article first appeared in FlyPaper by Soundfly. I reprint it here with permission (and I also stole their pictures of connectors – I hope they can forgive me!), and I encourage you to check out their courses. You can get a 15% discount code on a subscription using the promo code AJTRUMM15.
Unfortunately, you can’t connect audio gear with brainwaves yet – or even wifi (with notable exceptions). So, even in the modern world of digital awesomeness, cabling is still the heart of a studio and a stage, and something you should take seriously.
Here is everything you need to know about picking out cables – which isn’t as much as you may fear (what you could know – that’s a longer story).
Balanced vs. unbalanced
First you need to know the difference between balanced signal and unbalanced signal.
- Balanced signal uses three wires – ground, positive, and negative. Plus and minus carry the same information with opposite polarity. Balanced devices receive signal and flip one side’s polarity, bringing them back into phase – which happens to put noise out of phase with itself – cancelling it out. Sound like Greek? The key takeaway: Balanced connections reject noise.
- Unbalanced signal uses – you guessed it – only two wires. Simpler, cheaper, and noisier.
Unbalanced cables may work in short runs (under 25 feet – under 6 if you’re naughty), and some gear is unbalanced. If all your gear is unbalanced, using balanced cables won’t help you much, though it won’t hurt either. If your gear is balanced, you’re better off using balanced cables all around if you can afford it.
Older gear like vintage outboard gear, anything with RCA type connectors like record players, and instruments such as guitars and basses are all unbalanced.
Microphones, mic preamps, and mixers are normally balanced. Again, pick balanced cables unless money is an issue, the runs are short, and/or every single piece of gear is unbalanced (unlikely).
Speaker vs. instrument
If you’ve skipped ahead, you’ve noticed that you can tell a balanced cable from an instrument cable by looking at the connector. Unfortunately, that’s not so with speaker cables vs. instrument (aka guitar) cables.
Nevertheless, it matters. Speaker cables are unshielded, which means if you grab one to connect your guitar to your amp, you’ll pick up noise from other sources (the “Mexican radio” problem), interference from devices – and generally have a noisy, ugly result.
It’s even worse in reverse. Using an instrument cable on a speaker such as a powered monitor or separate amp/loudspeaker can cause major-league harm to your amp. Because instrument cables have smaller wire, you’ll be sending a high amount of current to your amp – way more than it can actually handle. Things may be fine at first, but eventually you could cause a short in the amp, melt the cable, or worse yet – look stupid.
So how do you tell the difference? Read the package and keep track.
Here’s a run down of typical audio connectors. Pro tip: if you can tell the difference between the first two, you’ll know if a cable is balanced or not by looking at the connector.
TS stands for tip/sleeve. Think of a guitar cable or a speaker cable (see above if you skipped ahead). Also known as quarter-inch mono or phone jack. Notice there are two terminals. The tip (literally) and the sleeve (below the little line). That’s two channels. Three guesses whether this is a balanced or unbalanced connector, and the first two don’t count. (Hint: Unbalanced.)
TRS stands for tip/ring/sleeve. AKA quarter-inch stereo or quarter-inch balanced. Notice the extra little line in the connector, creating a tip (literally!), ring (the middle part), and sleeve (as before). TRS connectors are – you guessed it – balanced. Or they can be stereo. Why? Because they have two discreet channels – so they could carry stereo information instead of balanced mono information. Take a look at your headphone connector and you’ll see a tip/ring/sleeve connector. This signal is split into two before it gets to each side of the headphones.
You’ll also see TRS connectors on one end of insert cables. In this case, the signal is split into two not for stereo purposes, but for output and return.
1/8th inch tip/ring/sleeve connectors are used for earbuds, many y-cables that you would use to connect your laptop’s headphone outputs to a mixer, and some headphones. Look for the three terminals on the connector – if you only see tip and sleeve, it’s not a stereo connector.
Mic cables. Old-school blokes call them cannon connectors. Unlike other types of cables, XLR cables are male on one end and female on the other. This is handy. Output is male (you know why). Input is female. Notice the three pins. XLR connections are balanced. Mics and mic pres aren’t the only place you’ll see them. They’re also used in AES/EBU digital cables (although the cable itself is a bit different), and you may come across an XLR patch bay.
Also called phono connectors. These are unbalanced. You’ll see the female side on mixers labelled “tape in/out”, on the back of consumer electronics such as TVs and video game consoles, and interestingly – as S/PDIF digital inputs on audio gear. Technically, S/PDIF cables are more robust, and it’s better to opt for a true S/PDIF cable for these connections, but a regular old RCA cable will do in a pinch. RCA connectors are also typical in the y-cables mentioned above.
There are of course many other types of connectors you’ll see less often. These include but are not limited to banana plugs (speaker/amp systems), speakON (stage monitors and pro PA stuff), BNC (word clock and video connections), optical (digital audio), DB25 (computer-like connections with multiple channels in a small space), Elco (similar idea to DB25), and tiny telephone or “bantam” (miniature TRS connectors typical for large studio patch bays – very space-saving).
That’s it. In fact, that may be more than you actually need to know. You’ll notice we didn’t talk about Monster cables and Mogami cables and gold lamé cables and thousand dollar per foot custom-made cables from Japan. All those things may be great, and they may float your boat, but for the most part, any solidly made cable will do the job – as long as you pay attention to balanced vs. unbalanced and speaker vs. instrument cables – and your connections.
Until telepathic wi-fi enabled audio is invented, we hope this helps.