NUGEN Audio has launched ISL, an intersample true-peak limiter that helps avoid introducing distortion into the sound when encoding audio files to compressed-audio formats. It will be on display at the upcoming 133rd AES Convention in San Francisco at booth 512.
Creating cleaner compressed files is an important consideration when looking to achieve “mastered for iTunes” status, a quality indicator that is rapidly becoming the recommended practice in the industry.
Most music is compressed using lossy codecs such as MP3 and AAC, which are prone to introducing distortion if intersample peaks are present in the original uncompressed audio.
ISL limiting addresses intersample clipping directly. Unlike traditional peak limiters, ISL measures and corrects for intersample levels, protecting against distortion that can be introduced when codecs such as MP3 and AAC are applied downstream.
“There is growing acceptance that intersample clipping causes problems with codecs, but it’s a relatively new notion, which is why there are so few tools to help,” states Jon Schorah, creative director of NUGEN Audio. “If your music is going to end up as an MP3 file or on iTunes, you need to measure and avoid intersample clipping, and that requires the right tools for the job. ISL eliminates the need for iterative processing to try and hit the mark.”
ISL gives complete control over peak levels in audio signals from mono to 5.1 by allowing the user to set the true-peak limit rather than the traditional threshold at which limiting begins.
ISL is intuitive to use and lets audio professionals mix with their ears, leaving the limiter to detect and eliminate potential problems. Designed for the transparent limiting of relatively dynamic high-quality audio, ISL can also be used to hard-limit and reduce dynamic range where required.
Using the standardized true-peak algorithms of ITU-R B.S. 1770 and related standards, ISL features comprehensive dBTP metering, adjustable channel linking, support for audio formats from mono to 5.1, adjustable ballistics, color splits, and peak indicators.
ISL is RTAS/AudioSuite/AU/VST-compatible and available in 32-bit and 64-bit versions for OS X and Windows at $249.