How to Position Dynamic Microphones for Recording
There are various types of microphones that work for different purposes. Some may perform well with vocals while others may be suited for instruments. Some work better with high-frequency instruments such as the violin, and some may record best with high-intensity instruments like the drums.
The truth is no single mic will work for all applications. There are various parameters such as the polar pattern, sensitivity, and diaphragm type that determine the final sound. One of the most crucial parameters is the positioning of the microphone.
For a sound engineer, finding the correct and most optimum position for a microphone is the most useful talent. First, you should train your ears to listen to the sound of the instrument. Finding the ‘sweet spot’ is an intuitive process, and it is usually the kickoff point for placement.
With dynamic microphones, positioning can play an important role in the final sound. EQ should generally be adjusted along with the positioning, or else it needs to be done all over again. Also, never place these microphones on the basis of sight alone. Listen and find the position that represents the most balanced tones of that instrument.
What are Dynamic Microphones?
Dynamic microphones are one of the many microphones type available in the market. They use the principle of electromagnetic induction to transmit sound. A typical dynamic microphone includes a diaphragm and a coil placed within the vicinity of a permanent magnet.
When you speak into the microphone, the sound waves hit the diaphragm which then moves with the coil relative to the permanent magnet. The continuously changing magnetic field within the coil induces a current which is dependent on the movement. This current gets converted back to acoustic signals by an output device such as a speaker.
Finding the Correct Spot
Finding the ‘sweet spot’ for the mic, where it will pick up accurate tones of the instrument, depends on the type of pickup pattern. Dynamic microphones mostly come with a tight cardioid pattern. Here are a few tips on how to choose the correct placement for dynamic microphones.
Cover up one ear and cup the other one. Listen to the sound of the instrument. The cardioid pattern generally picks up more from the front than the rear. Thus, it is crucial to place the source at the front of the microphone.
General Placement Rules
The following are a few general rules that you can follow for the most accurate sounds:
You may be tempted to keep the mic close to the source to avoid any leakage and noise. This may grant you more flexibility in balancing. Also, the heart-shaped pickup pattern of the dynamic microphone usually rejects any sound that is off the axis.
You can place the dynamic mic as close to the source as possible without polluting the sound with high-intensity sounds. In fact, you can put it within an inch of the source to get the low-frequencies accurately. Of course, it is not as sensitive to higher frequencies and may produce feedback. It is crucial that you do not place the front end of the mic directly in front of the speaker.
·Position in the Room
Whether it’s a recording studio or your bedroom, never position the mic in the center. It can often give birth to standing waves which may cause disruptions. At the same time, the mic should be well away from any walls or other reflective surfaces.
In short, place it just off the center of the room. This way, you won’t be in the center of the room and you’ll be away from the walls.
Different Positions for Different Purposes
The placement of the dynamic microphone also depends on the type of instrument you’re recording. Here are the general rules for the most common instruments:
It is best to place the mic as close to the source as possible. In the studio, we recommend using a light filter. A light filter is a small screen placed between the source and the mic that prevents over-pronunciation of words with P. Otherwise, your vocals may be littered with popping wind sounds.
2. Acoustic Guitars
To get the best and astounding sounds you need to use place the dynamic microphones 3-4 inches off the sound hole. As a result, you’ll find that all the low frequencies are also captured beautifully. It is never recommended to use two mics at the same time.
3. Brass Instruments
With dynamic microphones, it is best to blow directly into the mic. It will capture the low frequencies much more accurately.
During a gig, ask the player to step up to the dynamic mic and place their mouthpiece near the mic. Try finding the sweet spot so that the frequencies are balanced.
Use a large diaphragm dynamic mic in front of the kick drum. Place it inside the hole on the front head. Also, place one right at the snare head. Also, note that you should never use a bunch of dynamic mics together, otherwise you will be hearing loud annoying sounds like screeching during your performance.
Another variable in the correct placement of dynamic microphones is the source of the sound. Having the best recording equipment does not mean you will always get accurate sounds. The biggest variable is the instrument and the player. It contributes to about 50% of the accuracy.
On the other hand, the acoustics inside the room contribute to about 20% in the final sound. Thus, it is crucial to ensure proper acoustics of the room before proceeding to record.
You may instantly want to reach for the EQ when something doesn’t sound right. However, you should try the following first:
- Change the source of the sound, for e.g. the instrument.
- Alter the position of the mic until you find the most balanced one.
- Try tweaking the mic preamplifier.
- Try a different room.
- Change the player at the source.
All in all, following the above guidelines when it comes to dynamic mic placement can result in breathtaking sounds that are accurate. Once you get good sounds, recording and balancing the EQ will be much easier. Happy Recording!