Piano or Keyboard? Part I

Size does matter!  The first consideration when deciding whether or not to record an acoustic (aka "real") piano is -- size.  Will a full size piano fit in your home recording studio?  Do you own a piano?  If not, do you have muscular friends willing to assist in moving a borrowed piano into your home studio?  Moving a piano isn't fun.  But, let's consider what recording factors also have to be considered to record an acoustic piano.

How noisy are your neighbors?  Anytime an acoustic instrument is recorded without the use of an isolation/sound proof booth, consideration has to be given to the surrounding noises.  At my house noise is a big problem.  For example:  I have three active four wheeler riding kids, my husband is a sci-fi TV watching kind of guy, I have three barking dogs, and yes, noisy neighbors too.  So, why is this a big deal?  Almost fifteen years ago, a gospel group I worked with did a recording project at one of my friends house.  Aware of the noisy surroundings of the studio we chose to work from midnight to 3:30am because this was the most quite time.  Exhausted we sat down a few nights later to listen to the project, thus far, and could hear the engineer's house cat meowing on one of the tracks. (Grin)  In order to ensure that unwanted sounds are not picked up on your recording tracks its necessary to carefully analyze the surroundings.

Now let's consider the studios acoustics.  Novice often forget to consider the room acoustics.  A piano (like any other acoustic instrument) sounds completely different in every room.  It all goes back to the old sound wave and how it vibrates and travels.  Sound is affected by several factors, including:  the heighth of the ceiling, the size of the room, the amount of occupied space in the room, as well as the texture of the surfaces in the room.  Howstuffworks.com recently explained,

Sound is constantly being reflected off many different surfaces.  Most of the time the reflected sound is not noticed, because two identical sounds that reach the human ear less than 1/15 of a second apart cannot be distinguished as separate sounds.  When the reflected sound is heard separately, it is called an echo. 

Generally speaking, a sound (which is a vibration) causes a chain reaction of the continued vibration which travels through the air.  When the vibration hits a mass the vibration reacts.  The reaction is dependent upon the surface of the mass.  If the surface of the mass is hard, like tile, then it reflects and continues to bounce.  However, if the surface is spongy, like a carpeted wall, then the sound vibration is absorbed rather than reflected, causing less or no reverb aka "echo."  Think of the analogy that people sing better when they sing in the shower. Truth is, they don't sing better in the shower, but rather they sound better in the shower because the sound is reflecting so much it adds a lot of reverb to the sound causing it to soften and cover up quite a bit.

Establishing an understanding of the acoustics of your studio room will be an added resource when considering microphone placement for recording the piano track.  Here's my basic guide line for successful microphone placement:

• Is the sound too strong?  If the mic is too close to the source of the acoustic sound it can make it very difficult to get a good quality sound.  With the piano, a mic placed too close is likely to record the actual hammering of the keys, as well as, any squeaks within the framework of the piano.
• Is the sound too weak?  This occurs when the microphone is placed so far away from the piano, that when the piano track is played back, it sounds like its been shipped to another location far away.  You try to boost the gain and increase the recording input; however, it's not going to fix until the mic location is balanced out.  
• Find the sweet spot.  Believe it or not, every room has a sweet spot.  A sweet spot is the one place in any given room where stuff (pianos, guitars, TVs, etc) actually sounds better than in any other place in the room.  Usually it's in the middle of the room, but it's relative to the ears making the determination.  
• How many microphones do I need to record this instrument?  Bottom line, when you play back the recording and it sounds like its missing something, add another microphone to fatten the sound of the instrument you're recording.  If you use two microphones, pan one to record left and one to record right, then congrats you're now recording in stereo.  Another cool feature of additional microphones, is that you can pick up the sound at different wave widths that add rich texture to the sound quality.   

As you can see there's much to consider when recording an acoustic instrument.  However, I encourage you to give it a whirl because it is a great experience.