Difference Between Speaker Cable & Instrument Cable?

Is there a difference between Instrument Cable and Speaker Cable?

YES!!

Instrument Cable vs Speaker Cable

Instrument Cable

Instrument cable (commonly referred to as Patch Cable, 1/4″ Cable or Guitar Cable) is designed to carry a instrument level signal or line level signal over fairly short distances.

Instrument cables have 2 wires in them. One wire carries the signal. The other is a ground wire.

The signal wire is usually somewhere between 18 gauge to 22 gauge. (quite thin)

The ground wire is either twisted or braided around the signal wire in order to shield the signal wire from waves in the air that add unwanted noise to the signal. See Electromagnetic interference / radio-frequency interference (RFI) on Wikipedia for more information on this.

The longer an instrument cable, the more susceptible they are to picking up interference. So, if you have a 100′ instrument cable, it will very likely be noisy. (no matter how good the shield is) For this reason, instrument cables should be no longer than 25′. The shorter the better.

Speaker Cable

Speaker cable is designed to carry an amplified signal over short or long distances.

Speaker cables have 2 wires in them. They are both the same thickness and type of wire. One wire is positive, the other is negative. There is no shielding on speaker cables. Shielding is not needed because the signal traveling through speaker cable is amplified. The strength of the signal is way higher than line level. Radio interference does not affect the signal because it is too quiet to be heard in comparison to the amplified signal traveling through the cable.

The gauge of the wires in the speaker cable vary depending on how powerful the signal traveling through them will be and the length of the cable. The higher the amount of power needing to go through the cable, the thicker it should be. As well, the longer the cable is, the thicker it should be.

Speaker cables should be treated with the same respect as AC power cables. In fact, they are pretty much the same thing. If you have an extension cord with no ground, you can cut the ends off of it, and you will have a perfectly fine speaker wire. (a 2 conductor copper cable)

Can I use one in place of the other?

Both instrument and speaker cables may have 1/4″ connectors on them. They can be hard to tell apart, but are very different and should not be mixed and matched. If you aren’t sure if you are dealing with an instrument cable or a speaker cable, unscrew the connector and have a look at the wires.

What happens if I use a speaker cable for my guitar?

You will have a very noisy signal because speaker cable is not shielded.

What happens if I use an instrument cable in between my amp and my speaker?

You can damage your amp. (Think about a powerful water pump hooked up to a tiny hose.)
You could also melt the cable and potentially start a fire. Instrument cables are not high enough gauge to carry an amplified signal.

The low cut button. What does it do?

Mar21

Low Cut Button

When the low cut button on soundboard is pushed in, it engages a ‘Low Cut Filter‘ on that channel. (same as ‘High Pass Filter‘)

It’s called a low cut filter because it cuts out all of the low sound below a certain frequency.
It’s called a high pass filter because it only allows the sound above a certain frequency to pass through. Both the same thing.

High Pass Filter on Avalon vt-737sp

On the majority of soundboards that ‘certain frequency’ is fixed, hence only having one button for it. On most boards the low cut is at 75hz, 80hz or 100 hz. On some higher end consoles and studio gear, you are given a knob to control what frequency the low cut is at. Some even let you control how gradual or steep the cut is.

Why should I use low cut?

By using low cut appropriately you can achieve a cleaner mix, get more headroom out of your PA and reduce the chance of low feedback.

Low cut is, in my opinion, probably the most under-used feature on audio equipment. It is VERY valuable to have a low cut and can make the different between a clean mix and a muddy one.

Different sound sources produce different sounds with different ranges. (frequencies)

A Bass Amp can produce low bass all the way up to treble
A Guitar Amp produces mainly mids.
A Trumpet produces mids and treble.
Voices very, but generally produce sound from low mids to treble.

If you want a more in-depth look at what frequencies are produced from different sources, I recommend the following link.
Frequency Chart
(an interactive frequency chart)

Unless the sound source for your channel is producing fundamental bass sound, you should engage your low cut. Doing so will eliminate the amplification of unwanted low sound.

This unwanted sound can be:

Microphone handling or floor rumble (from bumping the mic or stepping on the floor that the mic stand is sitting on)
The popping of “P’s” and “B’s” from a voice
Unwanted electrical hum (60hz)
Other nearby sound sources (the bass amp on stage or the pounding subs that are less than 20′ away from your mic)

Low Cut on Soundcraft GB4

When mixing live, the question shouldn’t be, “Which channels should I turn the low cut on for?“.

It should be, “Which channels should I take the low cut off for?“.

My answer at most gigs would be:

Kick Drum
Floor Tom
Bass Guitar
Some Synths (depending on the sound)
Sample (depending on the sound – if there are bass drops, you definitely need it off)
Some Keyboards (depending on instrumentation)

Another plus to using low cut properly is, that when you reduce the amount of unwanted bass going through your PA, you will increase your headroom. This is because it is more work for your power amps to amplify bass. So again, cutting out the unwanted bass, will allow you to get more volume out of your sound system. Not to mention it will sound less muddy.

Low Cut on a Mackie Onyx 1640 Mixer

Mic Preamps: What do they do?

Mar9

Why do I need a microphone preamp?

The output volume of a microphone is very low. Most times, it’s too low to work with at all.

If you have a mic plugged straight into a Mixer or Audio Interface without a preamp, there will not be enough signal. This will result in no sound at all or extremely quiet and poor quality sound.

Modern day Mixers, Audio Interfaces and Audio Processing Units (compressors, EQs, FX, ect) are designed to accept a signal of +4dBu. The volume of typical microphone signal is -65dBu to -40dBu.

This is why a microphone preamp (mic pre) is needed.

Mackie DL1608 Preamps

Does it matter which microphone preamp I get?

Microphone preamps are controlled by just one gain knob and that’s it. Very simple! If all they do is increase the volume, it doesn’t really matter which one you get, right? …… Wrong.

Because mic pres boost the signal so much, they can really affect the sound. Similar to how the sound from different microphones vary.

A mic pre can color the sound to make it sound warmer, shimmery, fatter, brighter, darker, brittle, muddy, dirty or just plain bad.

They can also keep the sound very clean, transparent, neutral & accurate.

API 512c Preamp

Types of microphone preamps:

Solid State Preamps are small and maintenance free. The nicer ones can sound incredibly accurate and transparent. Generally they sound more neutral than a tube preamp. Solid State pres maintain a very consistent sound a low volumes and high volumes. However, if you push them to the point of distorting, the distortion they produce sounds very bad. (this is called clipping)

Tube Preamps have glass tubes in them. Over time tubes may fail and need to be replaced . Many people try putting in different types of tubes to get different tones from their preamp. Tube preamps are larger, they produce more heat and they require more electricity than solid state pres. Tube preamps generally add color to the sound. They have the potential to make things sound very pleasing. As you turn up a tube preamp, the sound changes. The harder you push it, the more dirty the sound gets. The distortion a tube preamp produces is musical and generally warm sounding. So, you don’t have to worry as much about clipping your tube pre. In fact, many people purposefully make their tube preamps distort to achieve certain sounds.

On the vast majority of soundboards (mixing consoles) these days, each channel is equipped with a solid state preamp. The microphone signal runs through the preamp before going through the rest of the board. (EQ, Aux Outs, Fader) Many audio recording interfaces come with solid-state preamps built in. I’ve also recently seen a couple of recording interfaces that had tube preamps in them. (solid state pres are much more common though)

Avalon Vt-737sp

Many standalone preamps include additional features like:

Signal Indicator Lights or VU Meter
Clip Indicator Light
Phantom Power
Pad
Low Cut
Phase Reverse
Unbalanced Instrument Input
Equalizer
Compressor
Impedance Selector

When it comes to microphone preamps, you get what you pay for! Don’t expect to get an outstanding studio quality pre for $100.

Dynamic & Condenser Microphones – The Difference

Feb24

There are different kinds of microphones? There sure are!

The two most widely used types of microphones are Dynamic Microphones and Condenser Microphones. Both types of mics basically do the same thing – they convert sound waves into electrical signal. However the way they accomplish this differs greatly. We won’t get too technical here, but because the technology inside Condenser Mics and Dynamic Mics are different, they sound different and they react different.

Shure SM58-LC Dynamic Microphone

How do they sound different?

Condenser microphones are more sensitive. Because of this they respond quicker to transients and generally have a more detailed and accurate sound. 9 times out of 10 a condenser microphone will be used on vocals in a recording studio. (or other things that you want to hear very clear and full)

Dynamic microphones are not as sensitive as Condenser microphones and don’t response as fast. This is not necessarily a bad thing though! Many times a dynamic mic will sound smooth and pleasing on a sound source where a condenser mic may reveal too much. For example: When I am doing sound at a live event and have singers that I have not worked with before (and don’t know their voice), I always use a dynamic microphone. This is a safe choice and will sound good. I could strike gold by choosing a condenser mic that works well with the singer and sounds spectacular. But, I could also have a very bad combination where the microphone reveals harshness in the voice and sounds bad. Dynamic microphones are safer and can sound very pleasing!

Also, the sound from a Dynamic Microphone is generally not a wide as the sound from a Condenser Microphone. What I mean by that is, it generally doesn’t have as high highs or as low lows. Again, this is not a bad thing! On many sound sources you won’t want to pick up really low bass or really high treble. For example an electric guitar amp, a harmonica or a snare drum.

Neumann U87 Condenser Microphone

How do they react different?

Being the more sensitive type, the Condenser microphone acts very much like the human ear. When someone stands next to you and talks, you can hear them loud and clear. Let’s say that person continues to talk and takes a few steps away. The sound may become a little quieter, but you can still hear them fine. A condenser mic will pick-up the sound like your ears. This is good and bad. A condenser microphone will also hear everything around you (people talking or the loud drum kit 10 feet away from you). Even worse, if you are amplifying the mic signal and sending it out of speakers, the Condenser Microphone can very easily pick-up the sound that is coming out of the speakers and create feedback (a loop of the microphone picking up it’s own sound that’s coming out of the speaker)

Dynamic Microphones are less sensitive. The sound source generally needs to be less than 2 feet away from the microphone in order to pick up the sound well. (Less than 1 foot is ideal) If you move the mic 15 feet away, the sound will be substantially quieter and almost impossible to work with. This can be a great thing though! That means the background sounds will be comparatively non-existent with a dynamic mic. For this reason, most radio announcers use dynamic mics. (Ex: Sennheiser 421, EV RE20, Shure SM7B) In a live band setting, having the background noise not coming through the dynamic microphone is a huge plus. As well, dynamic microphones have substantially less chance of feeding back. Dynamic mics are much more common for live singers for all of these reasons.

If you’re in a recording studio, you are in an environment that is sound proofed and acoustically treated. You generally don’t need to worry about background sound, especially when recording one thing at a time. A condenser mic will

pick-up everything. Unlike in a live setting, this is a very good thing.

Electro-Voice RE20 Dynamic Microphone

Other Differences:

A Condenser Microphone requires phantom power in order to work.This is normally supplied from your soundboard (or preamp in the studio) and runs into the microphone through the mic cable. Some Condenser microphones are powered by batteries that you can insert into them.
A dynamic microphone does not require power to use.
Shure Beta 87a Condenser Microphone

Condenser Microphones are much more delicate. A bad fall can end the life of a condenser mic.
Dynamic Microphones are generally very durable and can handle countless falls on the ground and keep ticking!

Condenser Mics and Dynamic Mics are both great for different things!

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Tag Archives: Q&A

Difference Between Speaker Cable & Instrument Cable?

The low cut button. What does it do?

Mic Preamps: What do they do?

Dynamic & Condenser Microphones – The Difference