Choosing the right microphone isn’t easy. Especially when there are so many different types available to buy. Maybe you want to record music, start a podcast, stream online, or even just need a new microphone for work meetings and calls. Regardless of your needs, making an informed choice before purchasing is essential. That’s exactly why I put this website together, to help those who need guidance and for technical jargon to broken down in easy to understand terms. In this article I’m going to answer ‘what is a condenser microphone?’ by looking at the different types, how they work, and their differences.
The Two Main Types of Microphone
There are actually just two main types of microphones you should be concerned about. Condenser microphones and dynamic microphones. As you here to learn about condenser microphones I’m going to start with them.
Condenser Microphones
Condenser microphones are more sensitive than dynamic microphones, which has its advantages and disadvantages. Firstly, they pick up detail, nuances, and high frequencies exceptionally well. This makes them superb in studio environments for recording singers, drum overheads, stringed and acoustic instruments. They are exceptionally versatile, which is why studio engineers often have an array to choose from during recording sessions.
The disadvantages of them being sensitive is that they will pick up room ambience easily. Of course, if your room sounds great then this isn’t a problem; but if you have bad acoustics, or noise -such as traffic, or city ambience- present, then a condenser microphone is not the best choice. They are also prone to feedback, so condenser microphones are very rarely used for live performances.
Condenser microphones use XLR cables and are powered by 48V. So, if you want to use one at home, you’ll need an audio interface with an inbuilt preamp, which will allow you to power them and connect them to your computer. If you’re not sure if what that is, be sure to read my article ‘What is an Audio Interface?’.
Dynamic Microphones
Dynamic microphones are less sensitive than condenser microphones. They are also very robust and can tolerate loud instruments exceptionally well. So, they’re great for drums and guitar amps, or anything that produces a lot of power. Dynamic mics also eliminate background noise well, which is why podcasters, streamers, and vocalists will use them when they don’t want any room ambience to be recorded. Dynamic microphones also use XLR cables, they don’t require phantom power but you’ll still need an audio interface to connect them to your computer. Now you know the two most basic types of microphone, let’s look at how a condenser microphone receives sound.
What is a microphone’s diaphragm?
Like all microphones, condenser microphones are built with a diaphragm. Just as a diaphragm is essential for us to function as it allows us to breathe consistently and rhythmically; a microphone’s diaphragm allows it to pick up vibrating sound waves.
A microphone’s diaphragm is made of a then membrane that vibrates when confronted with sound pressure variation. This energy continues to pass through the microphone’s components, which convert acoustic energy into electric energy. A diaphragm enables a microphone to function as a transducer, without one it simply wouldn’t do its job. Condenser microphones come in two main sizes, large and small. Both have their own advantages and disadvantages, let’s take a look.
Small Diaphragm Condenser Vs Large Diaphragm Condenser Microphones
Small Diaphragm Condenser Microphones -also known as SDC– are slim and pencil shaped, whereas large diaphragm condenser microphones -also known as LDC– are much bigger and rectangular shaped. Apart from just looking different, the shape and design of each type affects how it picks up sound and its characteristics.
Transient Response
Transients are initial high-energy high bursts of sound, such as when a drummer bangs a drum, a guitarist strums a chord, or when a saxophonist blows their sax. Both SDC and LDC mics respond differently to transients. Small diaphragm condenser microphones react quickly to transients with great precision and accuracy. This is because their small diaphragm responds well to high frequencies which have smaller waveforms. Large diaphragm condenser microphones respond a bit slower to transients than small diaphragm condenser microphones. That doesn’t mean they’re not accurate in any way, but it may be something to consider depending on what instrument you want to record.
Frequency Response
Small diaphragm condenser microphones have a very flat frequency response, with a range that extends beyond the human hearing range of 20,000kHz. As SDC mics have quite a flat frequency response, their sound tends to be more neutral and uncoloured than LDC microphones. This makes them a good choice when you want to record bright instruments cleanly without producing any harshness.
Large diaphragm condenser microphones frequency response is wide and flat, but with boosts in the upper range and roll offs at the top end. This can produce a natural presence that is pleasing on the ears, especially on vocals when you want a more ‘polished’ sound. However, depending on the microphone’s construction, it could create a harsh unpleasant sound. These are of course generalisations for both SDC and LDC microphones, but each microphone model and manufacturer is unique so it’s best to research them before buying.
Polar Patterns
Microphones pick up audio in different ways due to the polar pattern they have, this can include picking up sound directly in front, from the front and back, and all around in a 360-degree circle. Polar patterns have different shapes with each being suited to varying purposes. The precision of a polar pattern can be influenced by the microphones diaphragm size.
Small diaphragm condenser microphones polar patterns tend to have very concise and consistent polar patterns. Their small diaphragm is picks up little nuisances and transients well, allowing for a balanced and steady capture across the frequency spectrum.
Large diaphragm condenser microphones have polar patterns that are not as steady as SDC mics, because they capture low frequencies less consistently. The polar pattern becomes wider at lower frequencies and narrower at higher frequencies. This isn’t a bad thing though. LDC mics can be more forgiving than SDC mics. Fore example, when a singer is singing into a LDC mic, they are able move around more freely without any significant changes to the sound, whilst the low frequencies ream sounding lush and warm.
Noise
Keeping noise to a minimal when recording is essential. You don’t want to hear any hiss or hum when you start to turn things up. Large diaphragm microphones have the advantage here, as they produce less noise than small diaphragm condenser microphones. They have a better signal-to-noise ratio as they transduce more powerful signals.
Address Type
This refers to the where the on-axis angle of the microphone is, meaning the area that captures the sound most accurately. Small diaphragm condenser microphones have capsules that point out from the top of the mic, this known as ‘top-address’ or ‘end-address’. Large diaphragm condenser microphones have a ‘side-address’ where the capsule points out of the side.
How much does a condenser microphone cost?
Now you know how to answer ‘what is a condenser microphone?’. Condenser mics come in two different sizes and are more sensitive than dynamic microphones. LDC mics tend to have a warm and present sound, whereas SDC mics capture sound with more accuracy and consistently, having a more neutral sound. When you break it down it’s not so complicated but it’s essential to know which microphone you need for your purpose.
Small diaphragm condenser microphones are great for piano, drum overheads, stringed instruments, and recording acoustic guitar in stereo. Large diaphragm condenser microphones are also used for acoustic guitar, are superb on vocals, and they’re great for recording room ambience. But remember there are no hard rules in recording. Whatever you go for, just make sure to experiment and have fun.
Let me know in the comments why you’re looking for a condenser microphone.
Chris