Mastering the Art of Turntable Grounding: A Comprehensive Guide

Reviewed by
Last updatedLast updated: April 10, 2024
Prime Sound is reader-supported. We may earn a commission through products purchased using links on this page. Learn more about our process here

Whether you are an enthusiast who has just stepped into the mesmerizing world of high-fidelity (hi-fi) audio or an audiophile with a rich experience in dissecting and appreciating the nuances of sound, the quest for perfection is a shared journey. The humble turntable ground wire is a little-known component that can dramatically enhance the quality of your audio playback. We take you through the intricate details of this vital aspect of your sound system, helping you grasp its importance and its role in your sonic experience.

Understanding the Ground Wire

An often overlooked part of your turntable set-up, the ground wire, also known as the grounding wire, is a solitary wire designed to connect your turntable’s chassis to the amplifier. This simple connection helps to equalize the ground potential, or the zero reference level used for applying and measuring voltages, between the turntable and the amplifier.

Failure to ground your turntable can result in a small variation in the ground potential, leading to the formation of a ground loop. This ground loop can induce a 60-cycle alternating current to flow through your audio cables between your turntable and amplifier. This is particularly problematic because phono preamplifiers are incredibly sensitive and vital for processing the signal from your turntable. The result is an unwanted 60-cycle hum that is discernible and often annoying when selecting phono input.

In simple terms, a ground cable acts as a preventive measure, averting the occurrence of humming noises and enhancing the overall sound quality. Most turntables have a grounding wire, saving you the trouble of procuring one separately.

The Role of Grounding

While it is agreed upon that unnecessary hum is undesirable, understanding how grounding prevents such sounds is crucial. Why don’t the other cables in the connection pathway between the amplifier and the turntable eliminate the humming?

The answer lies in the unique purpose of the grounding wire. Unlike the other cables that carry sound from the source to the amplifier and then to the speakers, the ground wire’s job is to catch any extra electrical current. Think of it as a safety net, designed to catch any stray electric currents that could cause excess noise or potentially hazardous electrical charges.

A grounding wire is fundamentally a safety wire, intentionally connected to the earth, and remains inactive under normal operations. It’s akin to a bucket ready to catch any spare water, preventing the room from flooding. In this case, the water is the electrical current that could cause unnecessary hum or charge.

Humming Issues: Is It a Ground Loop?

While an ungrounded turntable is often the culprit behind the humming sound, it is not always the case. Identifying the root cause of the noise can save you time and ensure that you are addressing the correct issue.

Humming noise in a record player is typically a result of either feedback or a ground loop. It’s important to note that a ground loop hum is usually 120 hertz, while other hums are 60 hertz. Although this may sound too technical for the average music lover, there are simple ways to identify the type of hum.

Firstly, the sound produced by a 120-hertz hum is aggressive and high-pitched, whereas a 60-hertz hum is lower and more consistent. Another approach to identifying the source of the hum is to adjust the volume knob. If the hum’s intensity decreases as you lower the volume, it’s likely that the noise is caused by feedback or another issue unrelated to a ground loop.

Additionally, if changing inputs does not alter or stop the hum, it is likely a ground loop. If you discover that the hum is not a result of a ground loop, you can try a few quick fixes. Ensure that your turntable is placed on a flat, sturdy surface and that your speakers are not on the same surface as the record player. Also, keeping your turntable away from any static sources can help reduce the humming sound.

Is Grounding Your Turntable Always Necessary?

The general consensus is yes. Regardless of whether your turntable operates on a belt or direct drive, there is potential for a ground loop. While the ground wire does not conduct the electrical currents responsible for playing the music, grounding your record player can prevent a ground loop, enhancing your music-listening experience.

A turntable equipped with a ground wire clearly indicates that it needs to be grounded. However, some turntables with built-in phono preamps do not require grounding. If your turntable is equipped with a built-in phono preamp, which you prefer over a separate one, and there is no grounding wire included, you might not need to ground your turntable, especially if you’ve never experienced any sound issues. Nonetheless, grounding is generally recommended as a precautionary measure.

Grounding RCA Cables: A Necessity?

Simply put, no. RCA cables, by design, are inherently balanced and grounded. An RCA cable comprises two signal wires and one ground wire, all enveloped in a cylindrical, grounded shield. Due to the identical impedances of the two signal wires to the common ground terminal, RCA cables are generally immune to producing hum.

Locating the Grounding Wire

Finding the grounding wire involves a quick check at the bottom of your record player. The grounding wire is often attached to the underside of the metal turntable chassis, with a copper spade connector left unconnected. Traditional turntable ground wires are green, although they could come in any color. If your turntable is brand new, the wire might be neatly folded and secured under the chassis with a twist tie. Make sure to thoroughly check the underside of the chassis before concluding that there is no ground wire.

Substitute for a Grounding Wire

If your turntable lacks a grounding wire, you can use speaker wires as a substitute. Any insulated wire, preferably 18 to 20-gauge stranded wire, can be grounded. You need to ensure that it is correctly connected to the amplifier’s grounding terminal or establish a connection using gaffer tape.

Ground Wire Installation: How to Ground Your Turntable?

To ground your turntable, follow the steps below:

  1. Turn off your turntable and amplifier to avoid any risk of electric shock.
  2. Locate your grounding wire underneath the metal chassis of the turntable. If it’s not provided, prepare an insulated wire.
  3. Locate the grounding terminal on your amplifier or receiver, usually marked “grounded” and located at the back of the unit.
  4. Loosen the grounding terminal and make sure the grounding wire reaches it.
  5. Slip the ground wire spade connector onto the grounding terminal, tightening it securely but not excessively.
  6. If your amplifier lacks a grounding terminal, secure the grounding wire’s copper spade connector onto the amp’s metal box using gaffer tape.
  7. For a self-made grounding wire, strip about 6 to 8 mm of insulation from both ends of the wire. Connect one end to the chassis screw on the amplifier and the other end to the chassis screw on the turntable.

Once you’ve connected your amp and turntable, turn on the record player and check if the hum is gone. If your sound is clear and immersive, your work here is complete.

The Bottom Line

Understanding the role of a turntable ground wire is essential for every audiophile and music lover. Despite its often overlooked role, the ground wire is a pillar of a superior listening experience. Ensuring your turntable is properly grounded allows you to immerse yourself in the purest sounds and melodies as the artist intended. Thanks to the humble turntable ground wire, let every note and rhythm envelop your senses without the hindrance of an annoying hum.

Leave a Reply

Your email address will not be published. Required fields are marked *