Microphones: Part 2In the
first part we learned something about the different types of microphones, and how they work. This part should give a guide, in which situations and for which instruments you can use these different microphones. However, these are more pointers and some basics, not a guarantee for a perfect recording. You can use these pointers for the experiments of your own.
Single Instrument recordingsThe most common technique for production of Jazz-, Rock- or Popmusic is recording each instrument with a separate microphone. This technique allows to change the balance and the spatial effect of a recording without needing to take care of the conditions in the actual recording room. At the same time the timbre and the dynamic of each instrument can be influenced. Everything in the following guide is only appliable when the recorded instruments are really recorded separated from each other, means either in completely different rooms or at different times. Sometimes it is also possible with the right choose of directed microphones (Cardioid) or partition walls.
VocalsFor vocal recordings it is recommended to use a condenser microphone with a large diaphragm. Some microphones are suitable for this purpose, but comparing different ones is the best way to find out which one does the best job. Moreover, your taste also influences the choice of the right microphone.
Advantage of a large diaphragm is the insensibility against pop-noises, which occur at explosive-sounds like "p" or "b". A distance of about 20-40 cm is recommended. Smaller diaphragms can quickly lead into a distorted signal. Still you should use a pop-filter even when using a large diaphragm microphone.
The directivity should be cardioid. A omnidirectional microphone leads to a more spatial sound, which can have an interesting sound in a good sounding recording room.
You should mind and use the proximity effect. A lot of inexperienced singers don't know this effect, which often leads to problems while recording. Singers who are familiar with it can use this effect for their rendition.
When recording multiple vocalists, for example for backing Vocals, you can normally also use only one microphone. Only when there are more than 3 vocalists you should use a second microphone. If the vocalists however have difficulties hearing each other or themselves it is sometimes better to work with one microphone for each vocalist. This allows you to control the balance of the different voices. For these recordings you also should take a distance of about 20-40 cm from the microphone.
Acoustic GuitarDeep frequencies, mainly the fundamental notes, mostly come from the sound hole. Higher frequencies come from the table and from the Strings. If you want a high amount of overtones you adjust the microphones to the bridge, else you adjust it to the sound hole.
The best results are achievable with condenser microphones. Small diaphragms lead to a brilliant and clear sound, large diaphragms make the sound more round. The difference however is just very small. The distance of the microphone should be at about 20-50 cm.
You can also take pressure zone microphones, placing them on the floor about 1-2 meters away from the guitar player. They lead to a more spatial sound, however, you should have a good recording room to use them.
Sometimes Guitars have built-in pickups. These often won't give you a balanced sound. Except you want exactly such a sound, you should rather take a microphone.
PianoWhen you have the possibility you should always record a grand piano. An upright one is only a workaround and mostly give you an unsatisfying result. But also the grand is not that easy to record, because of its size. Most grand recordings are done with at least 2 microphones, sometimes even with 3.
The direction and the distance are responsible for the sound. If you want a percussive and hard sound you point the microphones to the area of the hammers. The distance can be around 15-40 cm. The more you spread the microphones apart across the range of the hammers, the more you can get an impressive stereo effect, mind you doesn't display the natural conditions. For a more balanced sound you can direct the microphones to the holes in the soundboard.
You can also use a pressure zone microphone for the grand by attaching it on the lid of the grand. However you cannot achieve a stereophonic recording then.
Double BassFor recording a double bass you can use a condenser microphone with a large diaphragm and cardioid directivity. Mostly it is directed to one of the both f-holes. When the double bass is plucked, a distance of around 20 cm is enough, when being bowed a distance of 50-70 cm reduces the bow noises.
Violins, Violas, CellosFor these you also choose a distance of minimum 50 cm. The most frequencies are directed upright to the ceiling, so you should place the microphone in this area. A condenser microphone gives you the best results.
Flute (concert flute)Significant for a flute are the strong blow noises. You can emphasize it by a small distance of 10-20 cm. However, you should watch out that the microphone is not blown on directly, so you better place the microphone from above. If you want less blow noises, you can place the microphone a little bit further away. This also reduces the effects of the flute player's movements. Condenser microphones are recommendable.
ClarinetThe Clarinet has an anomaly to watch out for: the bell (the end of the instrument, where the sound comes out) only emits frequencies above 5kHz, the rest is released through the keys. Thats why you should align the microphone to the bottom keys in a distance of at least 50 cm. A hard floor like parquet can give you a more shining sound.
SaxophoneBecause the most frequencies come out of the bell you should align the microphone to this part of the saxophone. However, you shouldn't place it too close, because else you have too much air noises. A distance of 50-70 cm also take away the effects of small movements of the saxophone player.
Because a saxophone can be very loud you should use microphones which don't distort quick. You can use condenser microphones with inbuilt pre damping, but also a good dynamic microphone can lead to a good result. Mostly they even sound fuller and smoother than condenser microphones.
Trompet and TromboneVery sharp high frequencies and a very high sound pressure level specify these both instruments. Thats why you should choose microphones which are more insensitive against high pressure levels, like only a few condenser microphones, or a good dynamic microphone. A distance of at least 30 cm is recommended. Moreover, you can avoid overdriving by letting the Trumpet or Trombone player play not directly in the direction of the mic.
Guitar ampsMore and more E-Guitars and Electric Basses are directly plugged into the mixer or interface and the signal is simply send through digital effect processors or software, which recreate the sound of amplifiers. However, recording a sound over a real amp still cannot be replaced by this. The alignment of the microphone is important for the sound. A distance of 5-20 cm is mostly applied.
The choice of the microphone is dependent of the maximum volume of the amp. An undistorted guitar sound can be recorded with a small condenser microphone, without having distortion in the recording itself. Loud and distorted sounds should be recorded with large diaphragm condenser microphone or even dynamic microphones. A comparison between microphones makes the decision easier.
DrumsThe most common technique to record drums today is having an own mic for each part of the set. You always have signals of the other parts in the record of one part, thats why a good choice of microphones and their alignment is important. Because the microphones are placed close to the parts of the set, high sound pressure levels and immense air currents lead to distortion when using condenser microphones. Thats why dynamic microphones are preferred.
Bass-drumNaturally the bass-drum is very deep and very loud. Small diaphragms will distort quickly, thats why you should use microphones with large diaphragms, preferably dynamic ones.
For the alignment of the microphone one main rule is applicable: The closer the microphone to the drumhead, the higher the impact sounds are recorded. You get a high amount of deep frequencies when you place the microphone on a layer with the resonance head. When placed outside of the Bass-drum you get a more spatial sound, but also you record more from the rest of the drum set with that mic.
You can use two microphones, one close to the impact point and one on the layer of the resonance head, so you can vary the ratio of impact and sound. However, using two microphones can lead to phase erasement. When standing around 40-50 cm away from each other frequencies around 800 Hz could be erased, but this doesn't influence the sound in a negative way.
SnareTwo problems occur when trying to record a snare drum: Because of a lack of space it is hard to place the microphones optimally, and often sounds of the HiHat are loudly recorded with the snare microphones. Thats why you should use a microphone with cardioid directivity to avoid the hit recorded on them. The microphone is adjusted to the rim of the drumhead with a distance of about 5-10 cm.
You can also use a second microphone for the bottom side of the snare, where the chains are located. Again you should be careful with erased frequencies. Best technique is to use two identical microphones and place them in a similar distance of each head. Then you shift the phase of the bottom microphone.
TomTomsEach tom gets an own microphone, however these microphones should be similar, so you have a balanced tomtom sound. Again dynamic microphones are a good choice. They should be straightened to the rim of the drumhead with a distance of about 5-10 cm.
You always should have a look for the cymbals hanging above the toms: Avoid them being recorded much with the tomtom microphones.
HiHatThe sharp sound of a HiHat should be recorded with a condenser or a ribbon microphone. You should place the microphone about 5-10 cm away, directed to the top of the HiHat. You should never align it to the gap between the HiHat cymbals.
CymbalsCymbals are normally recorded with two Overhead-microphones. Because of the impossibility to record only the cymbals, the overhead microphones are also used to give the whole drumset a spatial sound, which can be even enhanced by additional room microphones. You should use 2 similar microphones, place them a little bit away from each other, to have a stereo effect. Moreover they should be not too close to the cymbals: a distance of > 50 cm is already good.
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Finally, second part is out there, this time with some advice for practical use. However mistakes happen, be it grammar/typos or textual ones. If there are questions, misunderstandings, whatever: Post it here or pm me.