How to Ground a Turntable without Ground Wire
Turntables, also referred to as record players, are used to play audio recordings. In the simplest form, a turntable is a circular, rotating platform through which a vinyl record, or phonograph album, is played. These devices have been experiencing a resurgence in popularity. They are often used by disc jockeys (DJs) when making mixes, but have also found a niche in living rooms and college dorms across America.
Turntables range in price, quality, and features. They come in stereo-stacks and stand-alone versions. Some have built-in preamplifiers, while other will need an external one. Certain models are easily connect to a computer through built-in universal serial bus (USB) ports, while others are a bit more complicated should you want to connect them to your laptop.
Selecting the right turntable for you is a largely personal decision. However, make sure you research common complaints, praises, and uses for the turntables you are considering.
Anatomy of a Turntable
While each manufacturer puts their own spin on the turntable, there are several basic elements that are pretty standard. Below, we highly the basic hardware as well as the typically included controls and ports that will come with your turntable.
Basic Hardware of a Turntable
A turntable starts with a base. Your turntable components are built on this hard, flat surface. It also helps to conceal the gears and mechanics that could be damaged if left exposed.
The platter, which is where the record sits, spins through the use of a belt drive or direct drive.
- Belt Drives: A belt drive is an off-center motor that connects to the platter via a belt. While a belt drive offers significantly less vibration, DJs typically avoid using turntables that include them due to certain limitations. For example, the belt drive is slower to reach ideal RPMs and can be slow to queue a track.
- Direct Drives: Direct drives, on the other hand, attach the platter directly to the motor. This creates more vibrations, which can affect the sound quality. The higher torque means your direct drive speeds up quicker than the belt drive.)
A center spindle protrudes from the platter. This allows you to align your record up and hold sit in place while your turntable is playing. Certain models will include a separate spindle, called a 45 RPM adaptor, meant to fit larger record holes to ensure your album does not wobble while in use. Some turntable models also come with a slipmat. (Others come with the traditional rubber mat that help to hold the record safely in place.) Slipmats are typically found on turntables used by DJs because they allow the record to easily slide when needed while the platter continues to rotate.
The turntable tone arm typically includes several different components. First, you have the counterweight. Because records can be easily damaged, it is important that your needle glide across its surface instead of dragging through it. Your counterweight needs to be perfectly calibrated in order to allow the needle to do this. (Check your manufacturer’s guide to find out the exact specifications for your needle and counterweight!) The tone arm also includes your anti-skate element. As with the counterweight, this needs to be perfectly calibrated as well. Your anti-skate control keep the needle centrally focused on the groove in your record. Without it, the needle may wane to one side or the other, wearing it out faster, and distorting the sound the next time you play your record. The tone arm upon an arm rest when not in use. (Some models even include a plastic clip on top to help prevent the arm from accidental motion.) The cue lever assists you with gently lifting and placing your needle.
In the most basic sense, the tone arm connects the headshell, cartridge and needle to the pivoting mechanism and the counterweight. The headshell connects the needle and cartridge to the tone arm and holds it in place. The needle, which is more commonly referred to as a stylus by professionals, is the piece that physically contacts the record. The stylus, which pictures up the various grooves, indentations, and bumps conveys this directly to the cartridge. The cartridge then translates these vibrations into the sound we hear.
Controls and Interfaces of a Turntable
As with the hardware above, each turntable manufacturer tends to put their own spin on the controls you are given and the wiring. However, there are certain general expectations you can have when it comes to turntable controls.
You should obviously have a power switch. A start and stop button is also very typical.
Speed selection buttons are also a given. However, there tend to be variations between which speeds are included. The standard turntable should provide at least two speeds, 33 rotations per minute (RPM) and 45 RPM. However, certain turntables will include a third speed option, 78 RPM. This is because different records will require different speeds for optimum audio quality. (As a rule of thumb, a 7-inch single will typically play at 45 RPM, while an LP will play at 33 RPM. The RPMs are usually stated clearly on the record’s label.)
Turntables used by DJs will often come with a pitch fader as well. This allow them to quickly adjust the speed of the platter by a certain percentage. This is commonly used when combining different records.
Finally, on the back or the side of your turntable, you will likely have the wires, power cables, and essential ports. This is where the ground wire, if required, will be located, as well as any ports used for RCA cables or USB connectors.
Importance of a Ground Wire
Ground wires are an important feature on many turntables. A ground wire helps to eliminate unpleasant buzzing, hum or distortion. Referred to by professionals as a “ground loop”, this occurs because the chassis is connected to various components that are not operating at the same voltage. While not every turntable model requires a ground wire, you should not assume yours does not. (Regas, for example, do not require the use of a ground wire.)
The ground wire is most commonly attached to a “ground” screw on your turntable. The other end then connects to a “ground” lug on your preamplifier or amplifier.
Older model turntables will often explicitly call out where your ground wire attaches. However, this is not always the case. So what do you do when you cannot locate an already attached ground wire?
A Word of Caution about Ground Wires
As stated above, not every turntable model requires a ground wire. However, a great many do. Often, this thin piece of wire is included with the turntable itself. However, they can be easily removed, ripped off by a careless or clueless user, or simply missing. It is a good idea to check with your turntable’s manufacturer should you believe a ground wire is needed but missing.
That being said, the internet is full of do-it-yourself (DIY) advice. Some turntable owners recommend that you simply look for a screw on the motor of your turntable to attach the ground wire to. Other owners, however, recommend that you look for an area on the chassis. The audio earth is another potential source for your ground wire. Yet others recommend that you experiment with the ground wire, touching it to various metal parts on your turntable until the humming goes away. Once you find a location that stops the unpleasant hum, you should then figure out the best way to attached the ground wire to that spot.
However, it is important to note that touching a wire to the wrong spot can cause your turntable to short. This can permanently damage your turntable if you are not careful and is not advised.
When in Doubt, Ask a Professional
As professionals who deal with electronics every day, we highly recommend you thoroughly research any DIY method found on the internet today. It is important for you to take the appropriate cautionary actions when dealing with any device that has a live electrical current running through it.
On the other hand, if you want to be sure you do not accidentally destroy your record player, bring it to a professional electronic repair technician with turntable experience. (In fact, we would advise you not to attempt to ground a turntable unless you have explicit direction. Examples include directions from the manufacturer’s instructions or a clearly marked “ground” screw. We do not advise you to every put yourself or your electronics in danger. Nor do we advise you to ever arbitrarily touch wires to various pieces of metal on a device that has an active electrical current running through it.)
As stated above, it is important for you to do your research if you are interested in investing in a turntable. There are plenty of options for turntable enthusiasts of all levels, from beginners to advanced professionals. Finding the right turntable is personal, but understanding any well-known defects or common issues can help save you time in the end.