A codec (Coder/Decoder) converts an analog signal to a digital bitstream, and another identical codec converts the digital bitstream back into an analog signal. Codec's are used to encode audio for storage on digital mediums, such as CD's and computer files. Audio codec's are also used to transmit audio over digital transmission lines, such as SPDIF. Audio Codecs Audio codecs generally fall into two groups, codecs that use lossy compression and those that use lossless compression. Lossy Audio Codecs Audio codecs which use lossy compression include: MP3 AC3 AAC ADPCM Read More

Duplex simply means that the communications device enables users to talk to someone in another location and the person in the other location to respond to the user via the same type of device. As an example, when someone makes a telephone call, he/she is engaging in a duplex procedure. The same is true when voice to voice communication is done via a computer. Examples of Half Duplex Devices and How They Work In contrast, a half duplex enables only one party to speak at a time. The best example Read More

Home audio recording software has quite a few applications. You can create historical audio records of events, create audio versions of documents that you need for projects, and even just have fun. Here are a few examples of home audio recording software that you can download and enjoy with for no cost. Multichannel Recording Software You may want to record programs from your favorite Internet radio program, or set up a message center on your hard drive for your Internet phone account. What you need is a multi-channel voice recorder Read More

A vocoder is a device for analyzing and synthesizing human voice. The term itself comes from the words 'voice' and 'encoder'. It has many uses but its main function is in secure voice transmission. The vocoder is useful for voice encryption which ensures that only another person with the voice decoder can listen to what has been said. Thus, a vocoder is basically a voice encryption or encoding device. Interestingly, the vocoder has been around since 1928 (and has been widely applied in the music industry around the '70s). While Read More

A hydrophone is a type of microphone that is specifically designed to be used under water. Hydrophones depend on piezoelectric transducers to detect sound waves and other pressure waves coming from underwater vehicles, animals, and natural structures. Hydrophones were widely used in World War I, and II to detect U-boats (German submarines) and are still used today for underwater seismology, aquatic research, and recording deep sea sounds. While hydrophones can be used underground and in the air, they are specifically tuned to an acoustic impedance that is ideal for water. Read More

TOSLINK or Toshiba – LINK is a connection standard for digital audio streams. It is a standard which uses fiber optic cables. The important feature of fiber optic cables is that they convert audio signals into light impulses as opposed to electric signals. TOSLINK cables usually transmit their signals as the red LED lights. The TOSLINK standard was first developed by Toshiba to provide connections in its CS players. It soon caught on and became the most popular connection format for audio signals. It is mainly used to connect CD Read More

When someone receives the Windows error, “This device cannot start. Code 10 in audio driver,” it means that he/she has a bad, missing, or incompatible driver for his/her sound card. The very technical and confusing explanation for this message, according to Microsoft, is this: “If the device has a FailReasonString value in its hardware key, that string appears as the error message. The driver or enumerator puts this registry string value there. If there is no FailReasonString in the hardware key, you receive the following error message: This device cannot Read More

SPDIF, or the Sony/Philips Digital Interconnect Format) is used to carry or transport digital audio signals in consumer electronic equipment such as CD and DVD players, PC audio cards, and car audio systems over short distances. The digital signal can be carried over fiber optic (TOSLINK connectors) or coaxial cable (RCA connectors) and is also commonly used in home theater and stereo systems. SPDIF is based on the AES3 interconnect standard is capable of two 192 bit blocks (split into left and right channel data) which are divided into 12 Read More

Systems that use 5.1 channel speakers are used for surround sound applications and have been steadily growing in popularity throughout the audio industry for use in theaters and residences alike. 5.1 channel speakers produce sound that can be heard from all directions around a listener, simulating the effects of real sounds. 5.1 channel speakers are especially popular for 3D movie applications, which aid in the realism of the film. Since the advent of 5.1 channel speakers, however, the introduction of 7.1 channel speakers and 8 channel speakers to the market Read More

CD mastering is the art of transforming your CD before it is replicated in order to enhance its quality. Mastering can enhance the depth and resonance of a completed CD so as to optimize it for warmth and clarity of sound. It is therefore a crucial step in the final process of audio recording and can make the difference between a professional-sounding audio CD and an amateurish one. Process of mastering After recording your music either in a live performance or studio, the final version needs to be mastered. The Read More