Buying A Microphone - Everything You Need To Know
In this article we are going to tell you everything you need to know about choosing a microphone and the questions you need to ask before purchasing a mic.
What Do You Want To Use The Microphone For?
It’s seems like the most basic question to ask but knowing the primary purpose of the microphone you are going to buy is an essential part of the decision making process. If you are a songwriter and want to record your voice then that needs a different microphone than if you want to record a drum kit. You might want a microphone for voice over or podcasting, again the type of microphone you buy may differ.
Comparing Microphone Types On Lead Vocals - Real World Test
In this video we demonstrate how different microphones can change the sound of the voice. In this video Jess Orestano, the songwriter featured in the Pro Tools For Beginners video series kindly offered to provide some vocals for a simple, side by side test of some microphones. This isn't intended as much to be an exercise in finding the best vocal mic as it is a demonstration of the character of different mic types on identical source material. You can read the full article comparing microphones on lead vocals here.
What Types Of Microphone Are There?
Microphones can generally be divided into three common categories; dynamic, ribbon and condenser.
Dynamic Microphones - Example - Shure SM7b
In the case of a dynamic microphone a small coil of copper wire attached to the back of a light diaphragm which moves in relation to a magnet behind the diaphragm and creates an electrical signal analogous to the sound the diaphragm is being moved by.
Although the best examples are carefully tuned to be as flat as possible, dynamic mics tend to favour the midrange frequencies, the weight of the copper coil to which it is attached limits how quickly the diaphragm can change direction meaning their high frequency response is limited and also slows the response of the mic to transients, meaning they can smooth out spiky sounds in a useful way.
Ribbon Microphones - Example - Royer R121
Ribbons are electrodynamic mics too, in their case a thin, usually aluminium, ribbon is suspended in the field generated by magnet and by moving in response to air pressure variations a current is induced in exactly the same way as a dynamic mic but because the ribbon, which acts as both the diaphragm and the coil in a dynamic mic, is conductive it can act as both a diaphragm and the copper coil and is lighter than the heavy diaphragm/coil assembly in a dynamic mic giving better high frequency performance.
Nearly all ribbons have a fig 8 polar response and they are favoured by many for having a sweet top end which presents harsh sounds more favourably and a pleasing warm tone. Though tougher than they used to be ribbons are more fragile than other types if microphones. If you want to know more then check out Everything You Need To Know About Ribbon Microphones
Condenser Microphones
Condenser microphones use the small gap between a solid metal backplate and a flexible, metal-coated diaphragm to create an electrical capacitor. As the diaphragm moves in response to sound pressure variations, the capacitance of this arrangement changes in a way which is analogous to the original sound. Because there is no heavy coil on the back of a condenser mic’s diaphragm is can follow the sound waves’ pressure variations much more closely than a dynamic mic can, making it the most accurate kind of microphone. All condenser, and their close relatives electret microphones, need external power, usually supplied by phantom power from the mic preamp though valve/tube designs need external power supplies. Unlike dynamics and ribbons they are very sensitive and require much less gain from the preamp making them the best choice for quiet or distant sources.
Large Diaphragm Condenser Microphones - Example - Neumann U87
Large Diaphragm Condenser Microphones tend to sound more flattering than small diaphragm alternatives. Most of the classic studio condensers tend to be in this category. Some people assume that a bigger mic means better bass response but this isn’t necessarily the case. They do have disadvantages compared to small diaphragm condensers. They have higher self noise and poorer off axis response but in close miking situations these drawbacks aren’t significant.
Small Diaphragm Condenser Microphones - Example - AKG C451
Conventional wisdom dictates that small diaphragm condensers are best suited to high frequency sources and while there is some sense to this, particularly when it comes to off axis response at the top end, this isn’t a rule. SDCs are an excellent choice for acoustic instruments and drum overheads, indeed anything with a bit of sparkle. Advantages offered by small diaphragm mics are good off axis frequency response, lower self noise and higher tolerance of high sound pressure levels. This is why measurement mics are invariably SDCs.
How Much Will A Microphone Cost?
The good news is that microphones have never been better value, you can get a vocal microphone that will do a reasonable job for less than £100 and can be used on vocals, podcasting or guitar.
In a recent video Jamie Gibbons over at one of our valued partners - Studiospares - compares 6 microphones that all cost under £80 that can be used for recording voiceovers and podcasts. You can listen to all of the microphones and compare them in this article.
If you are serious about podcasting and want a great value microphone from a trusted brand then consider the new Sontronics Podcaster Pro - check out our full review Sontronics Podcast Pro Tested - Is This The Ultimate Podcast Microphone?
One of the most famous dynamic mics is the Shure SM58, however there’s even more choice than ever. We Offer You 7 Alternatives - Your First Dynamic Microphone Does Not Have To Be A Shure SM58
However, moving on from the budget end of the market a microphone can cost several thousand pounds, but for a professional general purposes studio microphone expect to pay between £500-£1000.
Microphone Modelling Offers Lots Of Mics In One
Several brands including Slate, Townsend Labs and Antelope have made great strides in mic modelling. This offers the buyer thousands of different classic microphones, some of them rare, for a fraction of the cost. We’ve covered mic modelling a lot on this blog, if you want to know more then check out our numerous microphone modelling articles.
We’ve never done a direct comparison of microphone modelling systems but Audio Test Kitchen, who specialise in microphone testing have covered so many of the current systems that the data is out there for all to see. We investigate the differences between modelling mics from Antelope, Townsend Labs and Slate. Top Modelling Microphones Compared - Townsend Labs, Slate And Antelope Tested By Audio Test Kitchen
Phantom Power
No it’s not something from a halloween movie, but the way some microphones that require it derive their power via the cable that connects to the audio interface. Most budget audio interfaces will include a phantom power switch that will enable you to power a microphone, it’s worth checking that your audio interface or mixer has phantom power especially if you are buying a condenser microphone as many of them will need it to pass any sound.
We have all heard stories about how providing 48v phantom power to microphones that do not require it can cause damage to the mic. But if that is the case, why do some interface and console manufacturers only provide global or sectional phantom power switching? In this article, we do our best to get to the bottom of the myths surrounding 48v phantom power with the help of some seriously qualified friends. If you are confused then read Phantom Power And Ribbon Microphones - The Myth Busted!
Microphone specs can look confusing, but ultimately it is possible to understand the numbers once you know what the values are telling you. This guide will help you make sense of them and help you to select the right microphone for the job.
Summary
To help, we have consolidated 30 of our most recent microphone reviews in this article to enable you to see the differences between them and see how they could fit into your workflow. If you are considering a new microphone, for your studio or on location then check out these reviews...