{"id":6743,"date":"2022-12-13T22:27:49","date_gmt":"2022-12-14T03:27:49","guid":{"rendered":"https:\/\/audioapartment.com\/?p=6743"},"modified":"2023-04-21T09:56:32","modified_gmt":"2023-04-21T13:56:32","slug":"why-do-speakers-hum-when-you-touch-the-plug","status":"publish","type":"post","link":"https:\/\/audioapartment.com\/instruments-and-equipment\/why-do-speakers-hum-when-you-touch-the-plug\/","title":{"rendered":"Why Do Speakers Hum When You Touch the Plug Jack or Cable? (Explained)"},"content":{"rendered":"\n

I’ve seen my fair share of odd habits among sound engineers and musicians. But one thing that always seems to baffle me is the tendency for some speakers to hum or buzz when you touch the plug jack or cable. It’s like they’re alive and trying to communicate with us through the power of electricity!<\/p>\n\n\n\n

But in all seriousness, there’s actually a scientific explanation for why speakers hum when you touch the plug jack or cable<\/strong>. In this post, we’ll delve into the world of electrical currents and impedance matching to uncover the truth behind the mysterious humming of speakers. So let’s dive in!<\/p>\n\n\n\n

Why does the speaker hum when you touch the plug jack or cable? <\/strong>When you touch the plug jack or cable of a speaker in a home recording studio, it can cause the speaker to hum due to a change in the electrical current flowing through the circuit. This change in current can disrupt the delicate balance of the impedance matching between the amplifier and the speaker, causing the speaker to produce a humming sound.<\/p>\n\n\n\n

Is it normal for speakers to hum?<\/h2>\n\n\n\n

In most cases, it is not normal for speakers to hum. Speaker hum is typically caused by a problem with the electrical circuit or the impedance matching between the amplifier and the speaker, and it can be fixed by identifying and addressing the underlying issue.<\/p>\n\n\n\n

However, there are some situations where a small amount of hum is considered normal<\/strong> and may not be worth worrying about. For example, some amplifiers and speakers may produce a small amount of hum due to the design of the circuit, and this hum may not be noticeable unless the system is played at very high volumes. <\/p>\n\n\n\n

Additionally, some speakers may produce a small amount of hum when they are first powered on, but this hum should quickly disappear once the speaker has warmed up.<\/p>\n\n\n\n

Typical causes of speakers humming<\/h2>\n\n\n\n

A variety of different factors can cause humming speakers<\/strong>, but the most common culprits are interference from other electrical devices in the home studio and electrical ground loops. Here are some of the reasons why speakers hum:<\/p>\n\n\n\n

1. Electromagnetic interference<\/h3>\n\n\n\n

Take note that the electromagnetic frequency range from 30 Hz to 300 GHz is prone to radio frequency interference (RFI), a frequent kind of EMI. Because of electromagnetic induction, electrostatic coupling, and electrical conduction, EMI will introduce noise to an audio signal. Electric current creates magnetic fields, while magnetic fields induce a current. <\/p>\n\n\n\n

Because of the aforementioned power mains, humming may be produced in both the audio wire and the speaker. Similar interference, noise, and hum in the audio conductors and, by extension, the linked speakers may be caused by adjacent and distant radio wave transmission.<\/p>\n\n\n\n

2. Electrical ground loops<\/h3>\n\n\n\n

Connecting electronic components in a manner that creates several pathways to the ground is known as a ground loop. It is preferable for a pair of points in an audio circuit to have the same ground reference potential. Different ground potentials exist between these two places in a ground loop.<\/p>\n\n\n\n

Suppose a mixing board and an active speaker are both connected to the ground in the correct manner. A speaker’s input is wired to the mixing board’s output. The shield of this audio cable is connected to the ground of both the speaker and the mixer, creating a closed conductive ground loop that protects the signal from electromagnetic interference and returns it to the source.<\/p>\n\n\n\n

Connecting the active speaker and mixer ground wires to the power mains and the building utility ground wire completes the closed-loop system.<\/p><\/blockquote><\/figure>\n\n\n\n

Connecting the active speaker and mixer ground wires to the power mains and the building utility ground wire completes the closed-loop system. You may find either 50 Hz or 60 Hz on the AC power mains, depending on your location. Due to the resistance of the ground conductor in the cable, a tiny alternating current (AC) voltage drop will be induced across the ground in the power mains.<\/p>\n\n\n\n

The produced 50- or 60-Hz interference may be audible as humming or buzzing in the speakers since audio signals are alternating current voltages between 20 Hz and 20,000 Hz.<\/p>\n\n\n\n

\"A
A home recording studio setup with an audio mixer, monitor, and speakers. Source: pexels<\/figcaption><\/figure>\n\n\n\n

3. Mechanical failure<\/h3>\n\n\n\n

The speaker’s internal hardware<\/a> may be at fault if there is a buzzing or humming sound. Hushing and buzzing may be caused by faulty equipment itself or by making the audio route more vulnerable to EMI and ground difficulties.<\/p>\n\n\n\n

4. Human conduction<\/h3>\n\n\n\n

Human conduction itself does not directly cause speaker hum, but it is possible for certain types of electrical interference to be caused by the human body. <\/p>\n\n\n\n

For example, if you touch a metal component in an audio system, your body can act as a conductor and create a small amount of electrical noise that could potentially contribute to speaker hum. However, this is generally a minor factor compared to other sources of interference in the system.<\/p>\n\n\n\n

How to fix speaker hum in 3 easy steps<\/h2>\n\n\n\n

Here are three easy steps you can follow<\/strong> to find and fix hum in your home recording studio:<\/p>\n\n\n\n

1. Identify the source of the hum<\/h3>\n\n\n\n

The first step in fixing the hum is to determine where it’s coming from. This can often be done by unplugging each piece of equipment in your studio one by one and listening for the hum to disappear. If the hum disappears when you unplug a specific piece of equipment, then that is likely the source of the hum.<\/p>\n\n\n\n

2. Check for ground loops<\/h3>\n\n\n\n

Once you’ve identified the source of the hum, the next step is to check for ground loops. As mentioned earlier, ground loops can be a common cause of hum, and they can be caused by multiple paths for the electrical ground to flow. <\/p>\n\n\n\n

To check for ground loops, try using a ground loop isolator between the source of the hum and the rest of your equipment.<\/p>\n\n\n\n

3. Check the impedance matching between the amplifier and the speaker<\/h3>\n\n\n\n

Another potential cause of hum is a mismatched impedance between the amplifier and the speaker. To fix this issue, you’ll need to carefully match the impedance of the amplifier and the speaker. <\/p>\n\n\n\n

This can often be done by consulting the manufacturer’s specifications for both the amplifier and the speaker and making sure that the impedance of the two is closely matched.<\/p>\n\n\n\n

If you want even more tips and insights, watch this video called “How to Fix Ground Loop Noise, Hiss, Buzz, & Hum (Simple & Cheap!)”<\/em> from the FireWalk YouTube channel<\/p>\n\n\n\n

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