While many 1/4″ instrument and 1/4″ speaker cables look almost identical from the outside, under the hood they’re nothing alike. Don’t let the similar size, black jacket, and 1/4″ connectors fool you. Take care in looking at your cable to verify what it was made for and that you’re using it for the proper application. Cables will often say whether they are “instrument” or “speaker” cables in small white lettering along the jacket. Speaker cables are often slightly thicker in diameter than instrument cables. And if you really want to make sure you can unscrew the 1/4″ connector barrel and double check for yourself. The below picture shows the differences you’ll see between the two at the solder points to the connector:

Last week I walked into a friends jam session to hang out and listen. He was showing me his boutique amplifier and some of his guitars. When he plugged his guitar in there was a terrible buzz & hum coming from his rig! We were both caught by surprise and immediately started started troubleshooting some of the common causes, such as bad connector or an A/C power source radiating too much EMI near by. I unscrewed one of the 1/4″ connectors on his “guitar”cable to see if we had a loose solder joint but instead found he was using a speaker cable. Unscrewing the 1/4″ barrel relieved a twisted pair of conductors with no shield (typical of a speaker cable), rather than once center conductor and shield you’d find on an instrument/ Guitar cable. We quickly swapped out the cable with a proper instrument cable, and walla, beautiful tone with no noise!

This incident let me to think, using the proper type of 1/4” cable whether it be for an instrument or speaker run is incredibly important and often doesn’t get the weight and attention it deserves while troubleshooting problems. In this blog we’ll discuss why you should only use a speaker cable between the power amp and a speaker and instrument cable for instruments.

A quick background in cable anatomy:

Instrument Cable  are made of a single small gauge center conductor (usually copper) then surrounded by an insulator. The insulator is covered by a braided or foil shield (used as a second conductor) which is then encased in a rubber or plastic outer jacket. The picture below gives you a visual representation of this:

Speaker Cables are made of two conductors (usually twisted together) of a higher gauge conductor (10awg to 18awg) than instrument cable. Each of these conductors has its own thin insulating jacket. This twisted pair of conductors is then encased in a rubber or plastic outer jacket. See example below:

Why they’re not interchangeable:
You shouldn’t plug your instrument/guitar into it’s amp using a speaker cable because guitars, specifically passive guitars, send out a very low level signal. This low level signal is very susceptible to noise induced from RFI/EMI from cell phone and radio towers, dimmers and florescent lights, electrical transformers, and other sources that are always around you. The shield around an instrument cable keeps most of these interferences from getting into your guitar signal. Because a speaker cable doesn’t have this shield, if you use it to plug your guitar in, you’ll generally get a lot of noise in the signal due to induced interference. You’re not going to hurt anything by using a speaker cable as an instrument cable, but you’re likely not going to get a noise free sound either.

You shouldn’t plug your speakers into your amplifier using an instrument cable because instrument cables don’t have low enough resistance to let speaker level voltages flow with ease. Essentially the amp would be trying to send all of its power down a small center conductor and a thin braided or foil shield! At low volumes you’ll likely not have any problems, but in the event you have a powerful amp and turn the volume up, you’ll likely hear slight distortion of the signal, the amp will have to work much harder and have less power to drive the speaker, and in some cases, could even start heating up the instrument cable to the point that it melts the jacket and creates an electrical short circuit! This could of course ruin your amplifier and/or your loudspeaker.

I hope this post was able to shed a little light onto what whats going on below the outside jackets of two very similar looking cables. If you have any further questions or comments on this topic, or have another issue you’d like to see us cover, please leave us a comment below!

Ask any guitarist what features influence their decision-making when buying a guitar and from most you’ll get the same response: wood, pickups, neck profile, fretboard radius, action, body shape and color. Apart from color, all of the above affect playability and tone, which should be the key criteria on which any buying decision is made. However, you rarely hear a guitar player mention scale length, and scale length has a significant impact on both playability and tone.

Scale length tends to be thought of as the distance from the nut to the bridge saddles – string length. But since nearly all electric guitars have adjustable saddles and acoustic guitars have a compensated bridge saddle enabling each string to vary in length and be intonated correctly, scale length is more accurately calculated as twice the distance from the inside edge of the nut to the middle of the 12th fret.

On a guitar, strings length is compensated to achieve good intonation, which means that string length is adjusted through saddle positioning, to allow for the fact that a string is stretched slightly sharp when fretting. Different string gauges require different levels of saddle adjustment. Hence, on an electric guitar the position of individual saddles will vary, some will be set further away from the neck than others, while on an acoustic guitar a single saddle piece will be set at an angle.

The two most common scale lengths for electric guitars are 24¾ inch, found on many Gibson-style guitars, such as the Les Paul, and the longer 25½ inch, found on many Fender-style guitars, such as the Telecaster, Stratocaster and Jazzmaster models. The scale length used by Gibson has caused some confusion. Some people refer to it as 24¾ inch, while others define it as 24⅝ inch. Confusion exists for two reasons. Firstly, Gibson’s scale length has varied over the years. In 1954 it was 24 ¾, in 1959 24 ⁹/₁₆, in 1969 24⁵/₈, and 1992 24⁹/₁₆. Les Pauls are currently advertised as having a 24¾ inch scale length. Secondly, Gibson uses compensated string length to define scale length, while most other manufacturers, including Fender, give the uncompensated scale length. Once a Les Paul has been setup correctly, the length of the low E string from the nut to the bridge saddle will be 24¾ inch if fitted with Gibson’s recommended string gauge, but it’s uncompensated measurement from the nut to the 12th fret will be closer to 24⁵/₈ or 24⁹/₁₆, depending on year of manufacture. Compensated measurement seems a strange way to define scale length. Because all the strings on a guitar have a different thickness and different players prefer different string gauges, compensated scale length will vary across all the strings on a guitar and from player to player, depending on the guitarists string gauge preference.

When selecting a guitar, scale length should be a key consideration. Woods, thickness, body shape, type of neck joint, pickups, and electronics all have their part to play in influencing tone, but scale length defines the source harmonic content with which all other components interact.

The 25½ inch scale length is renowned for producing a rich, strong, bell-like tone with a well-defined bottom end. It is the longest scale length commonly used for electric guitars. It offers more sparkle, shimmer and brightness than shorter scale lengths. Fender’s Telecaster, Stratocaster and Jazzmaster models tend to be fitted with single-coil pickups to accentuate these factors. On a 25½ inch scale guitar, the spacing between frets is longer when compared with shorter-scale guitars. Fret for fret, notes resonate on a longer string length. Bass notes are firm, clear and bold.

The harmonics on a 24¾ inch scale guitar are more densely packed than on guitars with a longer scale, which leads to a thicker, warmer tone overall. You just don’t get the same creamy tone out of a 25½ inch scale guitar that you get from one with a shorter scale.

To be tuned correctly, strings fitted to a guitar with a 25½ inch scale length have to be placed under more tension than strings on a shorter-scale guitar. Strings on longer-scale guitars will feel tighter and firmer than those fitted to one with a short scale. This affects playability. Because the strings on a shorter-scale are under less tension, they are easier to bend and fret. The wider fret spacing on longer-scale guitars also means that, depending on the size of your hands, they can be a little more difficult to play than those with a shorter scale. Fingers have to stretch further.

No matter what components you fit to a 25½ inch scale guitar, you’ll never get it to sound or play the same as a guitar with a shorter scale, and vice versa. Scale length is just so fundamental to the tone and playability of a guitar.