Sound, Microphones and Vox pops

To get us prepared with the various projects we have to do over the coming weeks, we have been learning about sound and how to record it. This has included a basic look into what sound actually is, a rather in depth look into the different types of microphones, as well as showing (and reminding) us how to record and use the basic functions of the sound program 'ProTools'. Within this blog I will include my basic knowledge of what sound is from the notes I wrote in lesson backed up by some minor research from the Internet in which i have used to give me a better understanding. I will also review my first few attempts at collecting and recording Vox Pops as well as using the equipment and 'ProTools'.

What is Sound?!

Sound is a change in pressure levels which in turn becomes vibrations. These vibrations travel through solids, liquids and gasses and at the right frequency's can be heard by humans. Sound travels through these matters as two types of wave, longitude and transverse. Longitude waves are waves that go parallel to their direction of travel where as transverse travel in oscillations (or ripples). A wave can basically be translated as a disturbance or variation in frequency.

Sound is measured in decibels (dB) and Hertz (Hz). Decibels are otherwise known as SPL (Sound Pressure Levels) or basically explained as amplitude/volume. Hertz is otherwise known as CPS (Cycles Per Second) or instead is basically Frequency/Pitch.

Random Facts: -
- The speed of sound is approximately 343 m/s (767.3 mph).
- Humans hearing is limited to frequencies between about 20 Hz and 20,000 Hz (20 kHz).

We also discussed Young's Modulus which is basically what happens to waves during compression and rarefaction. We looked at 'Bass roll off' and 'High frequency cut', the first in which cancels out the lower sounds and the latter in which cancels out higher sounds. We discussed 'In phase' and 'Out of phase', the first being where two frequency's work in tangent with one another and the latter being where two frequency's cancel one another out. Lastly we looked at the 'Doppler effect', the sound of a moving object to a stationary object.

In Phase/ Out of Phase

The Doppler Effect

Microphones

A microphone is a transducer that converts sound energy into an electrical signal.

There are two main types of microphone: -

Dynamic (Moving Coil) - A versatile Microphone, ideal for general use. They are relatively sturdy and resilient to rough handling. They are also better suited to handling high volume levels, such as from certain musical instruments or amplifiers.

Condenser (Capacitor) - Condensers also tend to be more sensitive and responsive than dynamics, making them well-suited to capturing subtle nuances in a sound. They are not ideal for high-volume work, as their sensitivity makes them prone to distort. A common power source for Condenser microphones is known as Phantom Power (commonly labeled as +48v).

Our further induction into microphones involved learning about the 'Proximity Effect', an effect that occurs when an increase in low frequency occurs the closer you get to the mic. Furthermore, this effect is combated by the 'Bass Roll off'. We also learned about the different types of condenser, ones with a large diaphragm and one with a small. The large diaphragm allows for better sustained sound whereas the smaller is better for transient sound. Dynamic microphones however soften transient sound.

Lastly we learned about Polar Response Patterns, a series of patterns that show the direction which sound can be received from a microphone.

Omni Directional

Uni Directional (Cardioid)

Hyper Cardioid

Shotgun

Bi-Directional (Figure of Eight)

Vox Pops

Being on a BTEC media course before the degree I did already have a little experience collecting Vox pops. Albeit when i did have to collect them it was only from a small selection of people (most of which I already knew) and whereas I was originally rather confident beginning this project, I soon found collecting the vox pops rather troubling.

Before we started we had to learn how to use the recording equipment, which included a FOSTEX FR Field Recorder and a Sony Mini Disk Player. Once again, I had learned the basics of these within the BTEC course and within time I started to pick it up rather well. There was some hiccups trying to get the equipment to work but we eventually got going and settled into the role's of sound men. My personal preference for recording would have to be the FOSTEX, as it not only records with a better quality but also looks a lot more professional. With three of us being in for this session, one of us had to remain with the FOSTEX (which had to remain plugged to a power supply in class, due to a lack of batteries) whilst the rest of us would go in search of people throughout the college.

FOSTEX FR Field Recorder

Before this however, we had to come up with a decent question to ask people on the chosen subject of 'Weston's Grand Pier'. I came up with a few idea's but decided to settle on a question regarding the piers development and what people's opinions were on its future. I thought this question would allow more response from people, as it seems more of an important subject considering the piers current state. The other two guys in class were also using questions that focused more on the pier before its demise, which further convinced me to research peoples opinions on a new piers development.

Once we had our questions ready and our recording equipment set up, a few of us went in search of people to get some vox pops (as well as bringing some back to class for use of the FOSTEX). This is where everything rather abruptly came to a halt for me as I soon realised it wasn't as easy as I'd originally thought it would be. This wasn't particularly an issue with confidence because whilst I may have struggled in the past, over the last few years my confidence has become a lot better. I have no real fear of speaking up or standing in front of people, although when it came to stopping passers by I couldn't really get it together and do it. I feel the main reason for this was because these were college students and teachers, people that I knew from experience wouldn't really have the time for a question (let alone being brought back to class). In short, whilst i had the confidence I feel i perhaps worried a little too much about people's response and therefore didn't really try. I did manage to get around 8 Vox pops, but this was mainly from approaching teachers, friends and other people that I knew.

The next time we experienced vox pops I was more determined to keep focused and approach people. Albeit this isn't really my forte and admittedly I'm not very good at it, but I was still set on giving it a good try and with this time being outside of college and actually with the public I felt it was a lot easier to approach people. The only slight problem I had with this was having to work in partners (due to only two recorders between four of us) as it limited our time, didn't give us a more thorough experience and ultimately didn't work out for me in the end. It also felt more intimidating going up to the people in pairs, and it seemed like my partners insecurities were holding me back and vice versa. Nevertheless we still went at it and my partner got through his vox pops first reasonably quickly and with good confidence. When it came to my turn, I was confident but wasn't half as quick and seemed to be approaching the wrong people. They all seemed to be turning me down for various reasons and I soon lost my enthusiasm for it. I did manage to get a good few voices in the end, but unfortunately the recorders battery ran out and had to finish early. As it turns out the battery for the microphone also ran out earlier on and therefore meant I hadn't picked up any sound for my last few people (which as it happens probably gave the best answers). Just one of the many problems that can be encountered I guess.

All in all, I don't think collecting vox pops is exactly one of my better personal attributes and given the chance I would much rather just hold the microphone while the presenter did the job of finding and talking to people. However I would like another chance eventually to try and combat this problem and I hope I can try and do better for a future project.

Websites used for research: -
http://www.mediacollege.com/audio/microphones/dynamic.html
http://en.wikipedia.org/wiki/Sound