Sound Recording Solutions
Sound Card Recorder
Powerful voice activated microphone recorder for Windows. Click here to learn more.Adaptive Transform Acoustic Coding
ATRAC (Adaptive TRansform Acoustic Coding) is a proprietary audio compression algorithm used to store information on Minidiscs and other Sony-branded audio players. It was first developed by Sony in 1992; the higher compression versions of ATRAC3 and ATRAC3plus followed in 1999 and 2002, respectively. It uses Quadrature mirror filters (QMF) and Modified discrete cosine transform to represent encoded audio. In year 2006, a hybrid lossless compression scheme was added to the ATRAC family. The latest version, ATRAC3plus, gives FM quality at 64 Kbit/s and near-CD quality at 256 Kbit/s. ATRAC3plus does not provide a recording rate at around 128 Kbit/s which is a major difference from previous versions. This is provided, instead, by the previous generation of ATRAC3 at 132 Kbit/s. This presents a problem for the average user. Which bitrate should be used for near CD quality? The 64 Kbit/s rate does not provide the quality of a mp3 at 128 Kbit/s, the 256 Kbit/s bit rate uses a lot of space, and the 132 Kbit/s rate uses the previous, and less efficient, version of ATRAC. Thus to achieve the same near CD quality as mp3, one must use much more storage space. Some see this as a serious problem for Sony. New formats recently made available, Sony says, rectify this problem: in late 2005 a wider variety of bitrates for atrac3plus was made available, making the full range 48Kbit/s, 64Kbit/s, 96Kbit/s, 128Kbit/s, 160Kbit/s, 192Kbit/s, 256Kbit/s, 320Kbit/s and 352Kbit/s. ATRAC3plus codec is used in HiMD players (e.g., "Hi-LP and Hi-SP"), Memory Stick players, VAIO Pocket, PSP console and ATRAC CD players. It is thought to be a hybrid subband/MDCT codec, though not much information has been released. It uses a relatively large transform window of 4096 samples, four times bigger than that of ATRAC3. The signal is split into 16 sub-bands before MDCT and bit allocation. The available data encoding rates are 48 kbit/s, 64 kbit/s, and 256 kbit/s. In the recently released Sonic Stage version 3.2 and 3.3 some more bitrates have been introduced, the available bitrates are: 48, 64, 96, 128, 160, 192, 256, 320 and 352 kbit/s. Minidiscs recorded in this format are incompatible with older players. Tests conducted in-house by Sony found ATRAC3plus at 64 kbit/s to be equal in subjective sound quality to MP3 at 128 kbit/s. However, this testing may have been biased in the choice of test material. Double-blind tests have generally found other versions of ATRAC to be inferior to most modern codecs (MP3, AAC, Vorbis), raising even more doubt about the validity of Sony's ATRAC3plus claims. To convert audio to ATRAC3plus you need Sony's SonicStage software, which is provided with Sony digital audio players. It is also downloadable from Sony. Contrary to what Sony states, unprotected ATRAC files can be played back on IBM compatible PC using the RealAudio software or the Liquid Audio plugin module for Winamp. It is possible to configure SonicStage not to add digital rights management (DRM). However, nearly all ATRAC files contain DRM, with the exception of those encoded with a very old version of a leaked ATRAC3 ACM codec.
Phone Call Recorder
Must have software for voice modem. Record all phone calls automatically, watch Caller ID information, create you own powerful answering machine. Perfect sound quality. Click here to learn more.3d audio effect - 3gp - a-law - aac - acm - adc - aiff - aliasing - amplifier - amr-wb - amr-wb plus - amr - apev2 tag - asf - atrac - audio codec - audio compression - avi - bitrate - bitrate peeling - chord - codec - comfort noise - compact audio cassette - compact disc - compression - compression artifact - compression ratio - contact microphone - container format - dab - data compression - digital audio - digital camera - divx - dolby digital - dolby digital plus - dsp - dvd-audio - dvd - effects unit - equalization - ffmpeg - flanging - fourcc - frequency spectrum - hi-fi - high-end audio - hiln - id3 - joint stereo - laser microphone - line level - lossy - loudspeaker - matroska - mcf - microphone - midi - mixing console - mp2 - mp3 - mp3 surround - mp3 sx - mp3pro - mp4 - mpeg-1 - mpeg-21 - mpeg-3 - mpeg-4 - mpeg-7 - mpeg - mu-law - musepack - music - mxf - nut - osm - parabolic microphone - pcm - perception - phonograph - pink noise - pqf - psychoacoustics - qdesign - quadraphonic - radio receiver - ratdvd - realaudio - red noise - reverberation - rhythm - ribbon microphone - riff - rmvb - sbr - signal processing - sound - sound card - sound effects - sound recording - spdif - speech encoding - speech recognition - speex - stereo - subwoofer - surround sound - synthesizer - tape recorder - tdm - tweeter - video - video compression - vob - voice analysis - vorbis - wav - white noise - wma - woofer