I have noticed many times people make big mistakes when buying a karaoke microphone. The most common mistake is that they end up buying an expensive device that offers much more than needed and it’s basically an over-kill. The main reason for this, as you can guess, is being confused about specifications and features given that most people have no time and patience for a thorough research.

My intention here is to provide you with a brief and easy to read guideline that will help you understand better this device and therefore make a better choice when purchasing one.

How does a Microphone work?

A Microphone is a typical example of a transducer. A transducer is a device that transforms one form of energy to another. In the case of a microphone, the acoustical energy is converted to electrical energy.

Let me restate this in a bit of a simpler way: a microphone converts the sound waves (produced by a singer or a musical instrument for instance) into an audio signal.

Microphones have a built-in diaphragm that vibrates when hit by the sound wave. The audio signal mentioned above is actually produced as a result of such vibration.

The generated audio signal will then travel through your amplifier, speaker, mixer or whatever electronic devices that would be present in your audio chain following your microphone.

 

Dynamic Microphone vs.  Condenser Microphones

The terms Dynamic and Condenser basically refer to the two main Microphone technologies. You don’t need to know about all the details of these technologies here.

This would be beyond the scope of this post. The most important take away from this section should be that Dynamic Microphones are the most suitable and recommended ones to be used with karaoke machines and from performance-price standpoint.

Moreover, the Dynamic technology offers a simpler but more robust design. These microphones are more resilient to rough handling which is particularly important when used with a karaoke machine where kids may be involved most of the time.

Dynamic microphones are also generally cheaper than their Condenser counter parts, can also handle higher pressure sound levels and therefore are more durable.

The condenser microphones offer usually a better sound quality and are designed mostly for professional grade studio or personal applications. This is the main reason why they are generally more expensive.

Microphone Specifications

This section is an attempt to summarize and describe, in the simplest way possible, the most relevant specifications you need to understand when buying a karaoke microphone.

At the end of the day, it’s only by using a microphone that you will get the real feel of its quality and therefore can figure if it may work for you or not. That said, if you have an adequate understanding of the specifications when purchasing such device, you can minimize the chance of unexpected surprises.

Pickup pattern: This parameter is also called directionality. It represents how sensitive a microphone is when picking up sounds from various directions. Microphones patterns can vary from one device to another and they depend on the applications for which the microphone is designed for.

There exist several different types of patterns. Let me give you some examples so you understand what exactly I am talking about here. Be patient, I know it may sound confusing and complicated at first but it really is not when you grasp the concept. So here we go:

A microphone with an omnidirectional pattern picks up sound evenly from all directions. This pattern actually looks like a circle with the microphone being in the center.

A circle, by definition, does not show any preference for any direction, if you know what I mean. As you may have already guessed, this is not particularly a good pick up pattern for a karaoke microphone. Stay with me and I will explain the reason for this in a second.

What we are actually looking for, is a karaoke microphone with a unidirectional pattern. A unidirectional microphone is predominantly sensitive to one direction.

This means, this type of microphones only “pay attention” to sounds coming from a certain direction and guess what direction would this be in the case of a karaoke microphone? Well this would be the direction of the sound coming out of the singer’s mouth and directly hitting the microphone.

Any other surrounding and unwanted noise coming from random other directions are basically ignored by the microphone. That’s exactly what we want, we don’t want the surrounding noise get mixed with the performer’s voice and get amplified inside the microphone.

This is basically all you need to know in terms of pick up patterns: when reading the spec, we want a microphone with a unidirectional pick up pattern, that’s all.

There are several different types of unidirectional patterns you may hear about when shopping for a microphone and the most common one is called Cardioid which means heart-shaped. Just for the fun of it and so your eyes are familiar with such pattern if you come across one in a product data sheet, I have included a picture of this type of pattern.

Note how this shape (unidirectional) is different from a circle (omnidirectional) and how it favors a certain direction from another.

Frequency Response: this parameter illustrates how a microphone responds to a range of frequencies. In the case of karaoke machines, typical range of frequencies that are acceptable, can extend from tens of Hz to 12 kHz or more.

The more flat the frequency response, the better the quality of the microphone will be. A flat frequency response means the microphone will pick up evenly the different frequency components of your voice and that’s what we are looking for. On the other hand, a non-flat frequency response can distort your voice and is an indication of a low quality microphone.

As you may remember from a previous section, a Condenser microphone typically offers a higher quality than a Dynamic one. The main reason for this is that the devices based on Condenser technology benefit from a more flat frequency response. Also, Condenser microphones, cover a wider range of frequencies especially on the higher frequency side. Dynamic microphones are known to have limited high frequency details.

Sensitivity: This represents the voltage a microphone can produce as a response to a certain level of pressure. The higher the sensitivity, the more voltage a microphone can produce for a given pressure level and therefore the less gain will be further needed to amplify the audio signal. In other words, the higher the sensitivity the better the microphone is and that’s all you need to know.

Impedance: This is another key indicator of the microphone quality. We are not going into details of how this parameter is defined here as this would be beyond the scope and intention of this post. All you need to know is that we are looking for a low impedance microphone for a better quality. Typically look for an impedance of 600ohm and lower and you should be just fine. The lower the impedance, the better the microphone will work with longer cables attached to it.

Power source: Remember from the previous section that a Dynamic microphone is a better choice when used with a Karaoke machine. The good news is vast majority of Dynamic microphones don’t need a power supply, one less of a problem to worry about.

Wireless vs. Wired

The main advantage of a wireless microphone over a wired one is freedom. The performer can move around without having to be tethered to the karaoke machine base through the microphone cables. Your whole setup will look more clean and there is less number of cables to manage.

The price to pay for this is not negligible though. The wireless microphones are more expensive and they operate off of batteries. This obviously implies an additional ongoing cost.

Also, one important point that is neglected most of the time by the consumers is as follows: the higher price of a wireless microphone is mostly due to digital transmit and receive technology associated with this type of device. In other words, you are not necessarily getting a much better sound quality by paying a higher price.

The biggest benefit that this type of microphones brings to the table is the freedom and granted, this is an important factor when purchasing a karaoke machine. Putting that factor aside, my recommendation would be to go with a wired one. This means you will pay cheaper and won’t need to worry much about batteries and related recurring cost.

Summary

Microphones’ various features and specifications may sound complicated and intimidating at first when we are not familiar with the terminologies. However, the guidelines for buying a decent karaoke microphone are straightforward and easy to remember. You really don’t need to understand fully the details. In below, I have recapped a summary of what we learned. It covers most important point you need to know and remember. Use this as your cheat sheet when shopping for a Karaoke microphone:

1. We are looking for a Dynamic and unidirectional microphone
2. The frequency range has to be from few tens of Hz to somewhere around 12kHz and up. The more flat the frequency response, the better the quality of the microphone. The wider the frequency range, the better the microphone will be.
3. A microphone impedance of less than 500 Ohm is good enough to do the job. The lower the impedance, the better the quality is.
4. The sensitivity is another indication of quality. The higher the sensitivity the better the microphone quality will be compared to a model that has a lower sensitivity.