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The Ideal Budget-Friendly Speech Audio Recording Equipment


Presently, there is a wider range of tools used in the production of audio media as compared to the past. Better methods of manipulating and capturing audio are developed with each passing day, to enhance the quality of recorded sound.

Apart from PDAs and laptops, the assortment of the available equipment used for audio recording include: tape recorders, memory recorders, disk recorders, and analogue and digital recording equipment. The main aim of this article is to assist you to make an informed decision when getting ready to buy audio recording equipment.

The information contained on this page is meant for a diverse group of people including students, speech therapists and researchers. The article largely focuses on handy equipment that can be used to capture audio media in the field within the available budget (the most expensive recorder mentioned goes for £650), which therefore excludes complex recording equipment used by Radio broadcasters or for mass communication in general.

The objective is to help you assemble an assortment of tools and equipment that have the capability to produce excellent audio recordings, which are good enough to be used for signal analysis. An example would be the use of a computer in the analysis of the vocal sound quality, format frequencies and fundamental frequencies. The audio recorders currently available in the market are meticulously constructed to ensure that all vocal recordings to be used in the instrumental analysis process are of good quality. This quality of vocal output is attained by ensuring that you have the right choice of a recorder, the perfect microphone and a good recording environment that is free from noise – ensuring that the audio recording settings are set to precision.

For each of the mention recorders their basic functions, advantages and short comings are mentioned. However, technology is constantly improving at a rapid pace. This means that what is relevant today might be outdated within the shortest period of time.

The Use of Cassette Recorders in the Audio Recording Process

walkman_sony

Cassette recorders are amongst some of the sound recording devices which have been around for a while. Initially the recorders utilized 1/8″ tapes with 1.875 inches/sec recording speeds. Modern cassette recorders were tweaked for efficient speech recordings, but they are generally unforgiving when the recording levels are not set correctly. They are not the best devices to be used when high-quality speech recordings are required. This is because they are prone to harmonic distortion and degenerating quality after years of storage. In the 90’s walkman recorders were the most preferred cassette-based audio recorders. Today it is difficult to find a walkman recorder in the market, because they have been edged out of the market digital audio recorders. However, before digital recorders came along the Minidisc Recorders were preferred largely because of their compact nature and disk use.

Using Minidisc Recorders for Speech Audio Recording

minidisc

This kind of audio recorder produces compressed audio media on a 2.5 inch magneto-photosensitive disk. A cartridge is used to shield the disks from damage. The ATRAC compression system invented by Sony is used to produce the audio media. These recorders are amazingly small in size and highly portable, with a great capacity of audio data handling. On the flip side, their small size makes them difficult to handle and operate.

The Minidisc recorders are designed to deter people using them from copywriting audio media, meaning you are not able to directly get rights to the compressed sequence bits that make up audio media. You have to compress and recompress the media before it can be used, and the compression and recompression process leads to loss of playback sound quality. A number of minidisc recorders are equipped with digital output capabilities to facilitate the transfer of audio media to a computer, but in order to do this you will require a PC with a digital audio input and a minidisc deck that has a digital output.

Currently there is a deliberation to decide whether there is any variance in speech recordings when using ATRAC compression method and whether it would affect instrumental analysis. Considering that the method is basically a time-domain coding that is used on varying frequency signals, the pitch is not likely to be affected by coding. However, the spectral envelope might be affected and there is no guarantee that it would not be negatively modified. It is difficult to know what effect compression will have on a recording, however small or negligible the change may have been the uncertainty is what causes a lot of concern.

The HiMD recorder is the latest recorder to be produced in the Minidisc recorder category. This new minidisc has two fascinating aspects that set it apart from the older models. For one, the HiMD recorders come with a Universal Serial Bus (USB) interface which has the capability to load audio media into a computer, which is only possible if they were produced on a recorder that supports analogue input.

Secondly, they utilize disks with higher memory capacities enabling the recording of vocal media for an hour or longer; whether in a compressed or uncompressed mode. One of the HiMD Minidisc recorders available in the market at the moment is the Sony NH700. It captures audio media in ATRAC3plus and Linear PCM recording to Hi-MD up to 1 GB. Normal MD blanks are reformatted to 300MB functionality since you can now use it as a USB disk. Doing so facilitates the use of a PC to transfer audio media from the line input.

The use of (DAT) Digital Audio Tape Recorders to Capture Audio Speech

dat-recorder

Digital Audio Tape recorders were designed to capture digital audio recordings on 6mm tapes. The recorders used an enhanced video recording technique, with rotating tape heads. DAT recorders have the ability to capture high-quality audio recordings, and they gained wide use in the broadcasting professional. The recorders capture PCM digital signals in 16-bit linear recordings at either 48000 or 44100 samples/sec speeds. Most AT recorders come with a digital output mechanism, enabling the digital transfer of recordings to computer systems. One of the main concerns about DAT recorders is their tape transport system and rotating head complexity. The devices are highly sensitive and they require regular maintenance and a high level of protection during transit.

Using the Solid-state Digital Voice Recorders to Record Speech

solid-state-recorder

The solid-state recorders store audio recordings on memory cards loaded on the device. The recorders often come with the choice to save the recorded audio either in compressed forms line the MP3 format or as uncompressed linear PCM formats. With larger memory card capacities, the solid-state recorders can record longer sessions on the compressed formats; however, in such instances the quality of the recorded audio is often lower in quality. Audio recordings intended for computer analysis should be recorded at data rates of about 192kbps to obtain quality recordings. In the uncompressed monophonic format, a one hour 16-bit recording recorded at a 44100samples/sec speed occupies a space of about 320MB. However, if the recording is maintained at a 192kbps data rate, the recording occupies only about 90MB of space.

Recording Speech Using Hard-Disk Recorders

hard-disk

Hard-disk recorders store both uncompressed and compressed audio recordings onto in-built disk drives with high storage capacities. The recordings are transferable to computers or they can be copied to CDs. There are few hard drive recorders in the market at the moment, but their use promises to increase progressively as a number of people embrace the new technology. One of the main reasons why they are not in high circulation is because they tend to be very expensive and they are generally not designed with portability in mind. However, a number of compact music players are available in the market and most come with live recording functionalities. They store the recorded audio on in-built low capacity in-built hard-disks, and come with external sockets to accommodate microphones. The iRiver H300 is an example of these portable music players, and it comes with about 20 to 40GB hard disk storage spaces. The recordings are then transferable to computer systems via USB ports.

Recording Audio Using Laptop Interfaces

laptop-audio

Laptops can be transformed into digital recorders, if equipped with high-quality external microphones. However, most laptops have sub-par microphone inputs and they are usually too insensitive to act as proper quality microphones. A separate digital converter and microphone pre-amplifier are required to work in collaboration with laptops for quality audio recording. With the introduction of USB microphone interfaces such as the M-Audio MobilePre have made the process much simpler. The USB interface comes with 3.5 mm microphone ports and it can support XLR cable connections. It can also supply Condenser microphones with phantom power and it is relatively efficient when it comes to noise reduction. It is important to have quality recording software installed on the laptop, with the ability to create audio files and store them on the computer system.

Using PDAs as Audio Recorders

sony-pda

PDAs or Palm-top computers have the ability to be used as portable audio recorders. These devices are often preferred for audio recording when compared to conventional computer systems, because they are highly portable, less expensive and come with better battery life. PDAs and Palm-tops also come equipped with network and memory interfaces making them the ideal option when compared to conventional computers. Few PDAs come with microphones and those that do are designed specifically for voice recording as opposed to quality audio recordings. PDAs are usually designed for telephony purposes with combination of a headset and microphone. For the purposes of quality audio recording, a Compact Flash interface accompanied with a quality pre-amplifier will be required to facilitate external microphone use.

Choosing a Microphone to Accompany the Selected Audio Recorder

Once an appropriate audio recorder has been selected, the next step is to choose a compatible microphone to accompany the recorder. The chosen microphone should be compatible to the recorder when it comes to connection and quality. Using a sub-par microphone with a quality recorder will result in equally sub-par audio recordings and vice versa.

The different types of microphones available

There are essentially two main types of microphones available in the market; the Condenser microphones and Dynamic microphones.
Dynamic microphones are considered as the ‘general-purpose’ microphones. They accommodate rough handling, because they are quite sturdy and flexible. They are the ideal choice for audio recordings where high volume levels cannot be avoided for example when amplifiers and musical instruments are part of the audio recording. They do not have internal amplifiers and external power sources or batteries.

Condenser microphones are more sensitive and they require external power sources or batteries. They are known to produce stronger audio signals and they are generally more responsive compared to dynamic microphones. They are however not ideal for audio recordings in high volume situations, because of their high sensitivity.

The different types of microphone connectors

Microphones come with different types of connectors, and this is an important aspect which should not be overlooked because it determines the microphone’s comparability with the audio recorder when it comes to connectivity. Although conversion cables are available to enable a microphone to be used with an incompatible recorder, it is much simpler to get a microphone which is connector-compatible with the recorder at hand.

The XLR connectors commonly accompany professional microphones. Each microphone comes with earthed shields and two signal lines. They are known to provide the best amount resistance to electrical-based interferences.

The Mini XLR connectors accompany lapel or lavalier microphones. The connector essentially connects the microphone to a radio transmitter or battery box. The other end of the battery box often has 1/4″ jack connectors or XLR connectors.

1/4″(6.5mm) stereo or mono jack connectors commonly accompany stereo microphones and professional microphones respectively.

1/8″ (3.5mm) stereo or mono jacks commonly accompany consumer-based stereo and mono microphones.

3.5mm mini jacks commonly accompany telephony headsets, which come with mono microphones and stereo headphones.

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Easy Tips for Recording Top Notch Audio


Good audio is very important for audio transcription success. You may be one of the best instructional designers who come up with the best engaging process available, but the sessions will definitely fall apart when the audio quality is wanting.

We have looked at why it sometimes makes sense to think about spending money on professional narration earlier. This is a good option when money is not a problem. The problem is that most people’s cupboards are empty just like Old Mother Hubbard. When you want to do the narration on your own or you are working with a limited budget, you can use some of the tips found below to get the best job is done. This time round we will look into the recording environment and the microphone. From here, we will plunge into some of the methods that can be used to achieve great sound narration.

1. Get a high quality microphone

You get value for money spent on sound equipment when it comes to the quality of the chosen microphones. To get great audio quality, you have to buy a good microphone. This however does not mean that you should go for expensive microphones; there are many times I have had to go for store-bought microphones which do not have brand names, because the companies I was working for did not have a lot of money to spend on sound equipment. They usually worked out okay especially when I followed the tips below:

Nonetheless, the truth remains that there will be a noticeable difference when the narration that has been recorded with a high quality and low quality microphones are compared. However, the perks that come with going for store-bought microphones is that a lot of money does not have to be spent and with proper use the quality of the recorded sound will be stellar. My Samsin desktop mic and the Plantronics headset have worked successfully. In my opinion, Blue Snowball mic looks great and has good reviews from people I know have used it.

I personally prefer a desktop mic, because it allows me to have more control over the quality of the audio. In addition to this, I find the idea of sharing a headset mic quite gross but that is just how I look at things. There are some people who grew up in the 60’s and don’t have a problem sharing the mic.
When selecting a microphone, it is always best to go for the unidirectional mic. This records the sound from a single direction. This is a great option especially for narration as it will only pick up sound from the narrator, thus you will not receive lots of ambient noise.

mics

Recently, I bought the Samson Go Mic and am in love with it. Audio quality is simply amazing. It goes for only $50 and I can record uni or omni directianl as it has 3 way record switch. It is worth the price. I did a few tests for Go Mic. I came up with a number of demos that differentiate a desktop mic and headset.

microphone

2. Maintain a steady environment

There are recording studios where sound can be controlled but this is only in an ideal world. However you might not have the skills to ask your boss to get the studio as asking him to part with $5 for a stock image is really hard. This means that you will have to think outside the box when recording.

Controlling the recording environment means that you will get better audio quality. One sure way is to have a consistent routine when recording. It is quite obvious that there are some times when you might have to take re-takes. You are able to match the quality of the audio by maintain the same procedures and environment.

  • Try using the same room, microphone and computer settings.
  • Measure the recording distance when using a desktop microphone meaning it is advisable to use a stand so that the same height is used all the time you are recording.
  • A screen can be used to get rid of the popping p’s that are present in most amateur recordings. You can make a personal one with little cost and no time.

screen

3. Eliminate as much ambiance noise as possiblef

Getting rid of the noise is very important unless you belong to the Quiet Riot group. This is because to get complete silence is very hard. This becomes very clear when you start to listen to the recording and get all sorts of noises. There are some companies that will pipe in white noise so that it is easier to concentrate as there will be less distraction from the surrounding conversations.

Either way, you want to eliminate the noise that you can control.

  • Turn off air conditioners and fans. Unplug machines in the office.
  • Direct the machine away from the computer when looking for a place to put it. You might not notice but the computer emits lots of fans noises. This is the fan hat keeps the machine cool and not celebrations for you.
  • Put a silence sign on the door. Ask people around you to be quiet. You can get a plane with a banner that instructs people to keep it down to fly around the office. Do whatever it takes to make sure the place is quiet. The Hume technique can be used when all others fail. It is an effective yet subtle way but it put the point across.

4. Make the sounds damp

The walls in a recording studio are designed in such a way that they absorb the sounds. You can try and do something similar to this. Cubicle walls are designed to absorb the waves in addition to getting the life from you dry bones. In fact i use my small cubicle that has been set up in the home office for recording and it has pleased me so far.

We have made a storage closet to be a makeshift recording room once. Rails were placed on the walls and blankets hang from it. This also helped in case we got stuck in the building for a long time.

There are some people who have used curtains and a PVC pip frame to make a portable studio. The frame could be assembled quickly and shower curtain rings were used to put up the curtains.

A portable sound booth can also be made. When you are not too sure of the knife handling skills it is better to purchase a Porta Booth.

soundbooth

Always remember that you are not an audio expert who is producing sound for Hollywood productions but for quality audio transcription process. But it is vital to learn about ways of recording and audio to do a great job. The post is a good beginning. More on Audio recording tips

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8 Tips to Use during the Voice Recording Process


The advancement of technology has seen to the influx of audio recording devices which are at the disposal of students and educators who deal with sound analysis. It is much easier to record sound at any instance whether through cell phones, laptop computers or the assortment of digital recorders available in the market. Video recording devices simultaneously record moving pictures and sound.

Novice media producers can notice right away if the recorded visual images are wanting in quality. They can spot shaky images, dark shots or over exposed images and effect the necessary changes for a quality end-product. This is however not the case with sound recordings; most people settle for sub-par sound quality, because they are unsure about what constitutes to good sound recordings.

Each year, I assign my multimedia students an audio podcast assignment. I always give them pointers on the common problems that they are likely to encounter during the audio recording process and give them tips to use to ensure that they come up with quality audio recordings. Here are 8 tips which my students find particularly helpful during the audio recording process.

  1. Find an isolated or quiet place for the recording – it goes without saying that the quality of an audio recording is as good as the surrounding environment. It is wise to go for carpeted rooms which results in ‘warmer’ sound qualities, as opposed to rooms with wooden floors which are prone to echoes.
  2. Minimize on sound distortions – Apart from technology-based distortions, there are several causes of sound distortion which everyone should be aware about during the audio recording process.
    • Person-based distortion such as the rustling of paper, shuffling of feet, creaking of chairs and excessive body movements which results in noise produced by the jewelry  worn.
    • Background noises are produced by distant radios, construction workers, phones, doors and TVs.
    • Humming sounds are produced by electrical equipment such as refrigerators, fans, fluorescent lights and AC systems.
  3. Adjust the recording settings to the right levels – the recording settings should be at the appropriate levels. Adjust the volume to a high level, without going beyond ‘the red zone.’
  4. Listen to the sound recording using headphones – it is important to monitor the audio recording as it is being captured to pick on possible distortions or problems and rectify them on spot. Monitoring sound through speakers usually gives a false feedback as well as odd echoes.
  5. Record natural sound – before beginning and after concluding the recording session, it is important to record the natural sound for about a second or two. This helps to capture the entire recording in its entirety as opposed to having abrupt entries at the beginning and fast cuts at the end. The natural sound can always be edited out if it is not required.
  6. Ask the interviewer and interviewees to speak clearly – people tend to speak too fast or mumble when they are aware that they are being recorded. Ask the interviewer and interviewee to speak clearly during the recording session. Remember that the main purpose of an audio recording is for the audience to hear what is being said.
  7. Set the microphone close to the speaker – the microphone should be set-up close enough to the subjects, but within a comfortable distance to avoid high-pitch pick-ups. The microphone should ideally be placed 12 inches from the subjects.
  8. Go for a handheld microphone – it is always best to go for handheld microphones or handheld recorders. The tip of the microphone should be held an inch away from the subject’s mouth and pointed towards the subject’s mouth. More on audio transcription

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