Tuesday, January 31, 2012

The Good Rule

Pretty soon, I will be meeting with my lab partners for our first assignment and our first practice for our 3 songs. I am pretty excited!

Getting a good sound is more complex than just the quality of the sound source. When recording a sound, whether it be a vocalist, an instrument, or environmental sounds, the good rule is always something to be considered and followed.


I have always heard that miking drums is a pain in the ass, but learning about all the different ways to get a good sound yesterday, I feel like it has everything to do with understanding how microphones works and through practicing.

We learned about 4 different ways to mic drums with 4 mics, 2 of which are the same kind. Theses techniques are called the A/B style, X/Y style, Glyn Johns style, and the M/S style. Before going into how to place the mics for each style, I want to go over some of the important terms about miking techniques from the book.

The Good Rule: Good musician + good instruments + good performance + good acoustics + good microphone + good placement = Good Sound!

3:1 Distance Rule: For every unit of distance between a mic and its source, a nearby mic should be separated by 3x that distance.

Proximity Effect: Causes an increase in bass response whenever a directional mic is within 1 foot of the source.
Directional Response: The sensitivity of the mic at various angles of the incident with respect to the front (on-axis) of the mic.

Sensitivity Rating: The output level, in volts, that the mic will produce, given a specific acoustic signal and input sensitivity rating.

Leakage: Whenever a signal is picked up by both the intended mic and a nearby mic, the signals can be combined during the mixdown process.

Equivalent Noise Rating: The electrical self-noise of the mic.

Frequency Response Curve: The measurement of output over the audible frequency range when driven by a constant, on-axis, input signal.

There are a few different kinds of microphones we used or will be using that I have drawn out for myself to recognize them easier.

As for miking the drums yesterday, we used the Sennheiser MD 421 to mic the bass kick drum, the Shure SM57 to mic the snare, and 2 AKG 414s for overheads.

The reason that dynamic mics are used in the kick drum is because dynamic microphones have a higher threshold and a lower frequency response.

<-----------------The X/Y Style. Think of this positioning as on an X/Y axis. The microphones are picking up sound from the opposite side of the kit in ration to where their stands are.

<-------------------The A/B Style. This is when the 2 overhead mics are on either side of the kit. The simple one conceptually.

<--------------------The Glyn Johns Style. One overhead is 6 ft. above the kit between the bass drum and snare pointing directly downward, and the other is pointing at the kit 6 ft. away on the other side.

The M/S Style. ------------------>
This one is really strange and hard to grasp, but it sounded soooo good in the studio. Basically, one mic is pointing at the kit with a figure of eight polar pattern and with its null points facing the kit, and the other is above it point at the kit with a cardioid polar pattern and its accepting side facing the kit.

Honestly, I have no clue how this ends up working, but I have a feeling I'll figure it out later this or next or the next week.... hopefully!

In the lab, there was a specific way of setting these four tracks up. The M/S was the only one that had more steps.

So, you duplicate the side mic to get S and S1, or Side Prime, and on one of the duplicates, apply
TDM > Other > Trim to put it out of phase.

When putting a track out of phase, the volume of that track will automatically go down 10db and thus, should be slightly louder than the other duplicate. This creates a pretty awesome sound that really was mind-blowing!

Some really cool new key strokes we learned yesterday that will prove very helpful are....

  • ; (semi-colon) P - Moves up and down the tracks!
  • Shift S - Solo of selected track on
  • Shift M - Mute of selected track on
  • Shift R - Record enable for selected track
  • Shift I - Turns on the Input Monitor for selected track. 
Also, when the solo button is applied to the board track, protools wont record from the corresponding mic and it wont show up on the corresponding track! But, when the solo button is applied in protools, the sound is only soloed and it still is being recorded. 

This is a drawing of how the cables must be placed on the board to achieve recording. On the other side of the wall, there is the patch panel that corresponds to the board as well. So, the bass mic is in patch panel 1, the snare mic is in patch panel 2, left overhead is in 3, and right overhead is in 4. Its not too difficult once you look at it a few times!

I'm dreading the rest of the plugs and what they do....


So, I had a pretty fun class learning how to set this all up and I can't wait for tonight... Or tomorrow morning's Improv class!

A Dynamic World Condensed into the Microphone

As my third semester at CSUMB starts to unfold, I am realizing how incredibly fortunate, happy, eager, and excited I am to learn, get my hands on a board, and make awesome music with some of the most awesome people ever!

The microphone has been a big part of my life since I was about 2 years old and I am almost ashamed to say that I had no clue how they even worked, apart from plugging it in, let alone how incredibly intense they are!

There is a huge, dynamic world condensed inside of each microphone that, when used correctly (or incorrectly in some cases), are so much more than just a way to record sound.


There are 3 kinds of microphones: Dynamic, Condenser, and Ribbon.

Transducer: Device that changes any one form of energy into another. Windmills, hydraulic pumps, solar panels, and even our ears are transducers!
Mics change air pressure, or sound in this case, into electrical signal. And every recording starts within a microphone that captures the sound.

Electromagnetic Induction
When a conductor moves across a magnetic field, it creates a change in flux proportional to the movement. Air pressure can move conductors in magnetic fields and generate equivalent electrical signal.

The Carbon Microphone
They have narrow frequency responses and are rarely used today, but were used in telephones. The carbon granulates separate 2 plates that react to air pressure.

Dynamic Microphones
These kinds of microphones use a mylar diaphragm with a voice coil to achieve electromagnetic induction. They get their unique sound from voice coils which take energy to move and to stop. They can also handle high SPLs, or sound pressure levels, and are rugged in their construction making them really great for live application.

Condenser Microphones
These kinds of mics are based on the electrostatic principle. They have 2 polarized plates that create a capacitor out of the air between them, as the air pressure moves the plates closer together. Also, these kinds of microphones require an extra voltage boost called Phantom Power.

Phantom Power = +48 volts sent to the condenser microphone to give it that extra boost.

Some condenser mics are large, and some are small. Large diaphragm condenser mics are more common and have a 1 to 1.5 inch diaphragm and are capable of creating a variety of polar patterns.
Small diaphragm condenser mics have less than 1 inch diaphragms and are highly directional and sensitive in the higher frequency ranges.

Piezoelectro Microphones
These cool mics rely of natural substances that generate electric charge in response to pressure. They are used as boundary microphones and especially for acoustic guitars.

Polar Patterns
All microphones are directional. Every microphone has a front and a back end. The major polar patterns include omnidirectional, cardioid, supercardioid, hypercardioid, and figure of eight.

  • Omnidirectional: Picks up sounds from all directions, is typically never used off-axis, and don't experience the proximity effect. 
  • Cardioid: Gets its name from its shape--a heart! This is the most common directional mic. 
  • Supercardioid: Gets sound from the back as well as from the front and wont accept sound at any angles from the back. 
  • Hypercardioid: Increased acceptance from the back and increased rejection from the angled back sides. 
  • Figure of Eight: Picks up sound from the front and from the back, but has a lot of resistance from the sides.
Frequency Responses
This is the quality that makes microphones sound unique. There is a proprietary hump that will hype the sound unnaturally at a certain point in the frequency. For example, the Shure SM57 is used to mic the snare drum because its proprietary hump hypes the perfect frequency where the snap of the snare lies. 


In a few hours, my group (Kevin Lienhard, Collin Atkinson, Orion Navaille, Michael Glines, Nick Brumme, and I) will be completing our first lab designed to get our hands on a mic and experience how to record with in and where is sounds the best. 

I am so excited for this semester and I am so shocked that I am learning so damn much within the first week! So, the next few blogs will also revolve around the microphone and how to use it.