Reference Design

Two-Channel Audio Equalizer Filter in a Single Chip

Quickfilter Technologies reference design allows single QF1D512 SavFIRe (Simple and versatile FIR engine) IC to be configured to provide multiple channel filtering in a single device. Using this solution, device allows designers to implement audio equalization for both the left and right channels.

Source: Quickfilter Technologies, Inc.
6/26/2008

The Quickfilter Technologies QF1D512 SavFIRe (Simple and versatile FIR engine) is a programmable digital filter designed for seamless insertion in the serial data path of a digital signal or used as an FIR coprocessor. This specific circuit example shows the device operating between the analog inputs and outputs of a codec to provide a complete equalizer function. Virtually any filter can be implemented which will operate on the left and right channels independently. In this configuration, exceptionally high quality filtering is available over a broad range of ADC data rates with resolutions up to 24 bits.

In the two channel equalizer configuration, the QF1D512 SavFIRe IC can implement, as an example, a 200-20K Hz band pass filter. The filter will reject better than 24dB per octave in the transition band based on a 44.1 kHz sampling rate. With the Quickfilter QuickPro(TM) design tools, the user can also implement a free form editor for a virtually infinite array of "sound shaping" possibilities.

This configuration can be applied to both wired and wireless audio systems including wireless speakers, stereo headsets, docking station for iPods(R), other MP3 players and satellite radio systems, and audio systems for stereo networks.