FreqTweak is an open-source tool for real-time audio

Audio frequency

An audio frequency or audible frequency is characterized as a periodic vibration whose frequency is audible to the average human...

 spectral

Frequency spectrum

The frequency spectrum of a time-domain signal is a representation of that signal in the frequency domain. The frequency spectrum can be generated via a Fourier transform of the signal, and the resulting values are usually presented as amplitude and phase, both plotted versus frequency.Any signal...

 manipulation and display. It is free software

Free software

Free software, software libre or libre software is software that can be used, studied, and modified without restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with restrictions that only ensure that further recipients can also do...

, available under the GNU General Public License

GNU General Public License

The GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....

. FreqTweak can (and is supposed to) be connected to other audio software using the JACK Audio Connection Kit

JACK Audio Connection Kit

JACK is a professional sound server daemon that provides real-time, low latency connections for both audio and MIDI data between applications that implement its API...

.

Description

FreqTweak is FFT

Fast Fourier transform

A fast Fourier transform is an efficient algorithm to compute the discrete Fourier transform and its inverse. "The FFT has been called the most important numerical algorithm of our lifetime ." There are many distinct FFT algorithms involving a wide range of mathematics, from simple...

-based, and supports up to 4 channels. An FFT analysis is applied to each audio channel, and every individual frequency band can have a different effect applied to it. In version 0.6.1 the following effects are available:

• EQ cut/boost
  Equalization
  Equalization, is the process of adjusting the balance between frequency components within an electronic signal. The most well known use of equalization is in sound recording and reproduction but there are many other applications in electronics and telecommunications. The circuit or equipment used...
  
  
• Pitch scaling
• Gate
• Compressor
  Audio level compression
  Dynamic range compression, also called DRC or simply compression reduces the volume of loud sounds or amplifies quiet sounds by narrowing or "compressing" an audio signal's dynamic range...
  
  
• Delay
• Limit
• Warp

External links

• http://freqtweak.sourceforge.net/
• Project's page at sourceforge.net