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FIEO (Four In Eight Out) DSP

FIEO the natural successor of our previous DSP, simplifies & succeeds the requirements of todays DSP’s.

This is an active DSP with a built in 4 ch amplifier focused on upgrading & improving OEM systems with accuracy & unique features.
The 4 inputs are the following; High level (signal input directly from your speakers with the option to use the 4 x 30 w built in amplifier), Low level (RCA singal input with optional output amplification via built in amplifier), Bluetooth 5.0 and PC connectivity through USB.

On the output side there are 8 channels, preconfigured as front left to right tweeter, midbass & rear left to right fullrange. The remaining 2 channels configured as channel 7 & 8 are full range center & subwoofer. The option of running all channels as fullrange, highpass or even bandpass is possible in the software as well as the “Tweak N Tune” app.

Tweak N Tune

31 band EQ along with  3 different crossover configurations; Butterworth, Linkwitz Riley & Bessel enables you to tune like a pro. It’s even possible to blend the crossovers i.e. Buttworth as a Highpass & Linkwitz as Lowpass. Slopes of each crossover ranges from 6 dB ~ 48 dB. Plenty DSP’s have limited advanced features to the laptop only, but the RAGE FiEO with its unique app has everything at your fingertips.

Can’t find the EQ adjustment you specifically require, even though the DSP offers both parametric and graphic selection, fear not. All bands are configurable, so you can select the band closest to your spec, type or scroll to the desired frequency and done! Even if you don’t want to type, you can even drag & position the band where you want.

Struggling with time delay?

Miliseconds, cm or inches are all selectable on all channels. The adjustment can be done by typing in or by scrolling up or down. The speaker positioning next to the graphic layout of the vehicle simplifies the adjustment and gives you a way better overview of what is being tweaked.
There is even a “graphic only” selection. In this mode you can drag the delay towards a specific point while adjusting all channels at the same time. This feature is a huge time saver and gives you a good starting point for further adjustments.


Adapters, modules & added charges are things of the past. The RAGE FiEo offers a built in Wifi connection straight out of the box. There’s even a simplified IR remote for channel selection, volume & track selection.

The DSP GUI software can be downloaded below, the “Tweak N Tune” app will be available on Google Play and app store. To open the software after download on this website, you will need to unzip the file with the appropriate program;  winzip / winrar etc.

FiEo Manual   

DSP Software

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