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Everytime I want to create a new eq for my BTR17's built in parametric features I can never get it to be "Just right." And specifically the 'Custom Parametric' option is lacking, particularly in being able to set a minimum and maximum pre gain or be able to sacrifice upper db range to get a higher dynamic parametric eq.

Describe the solution you'd like

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• Support for the new Fiio BTR1X series of BT DAC&AMPs built in customizable parametric EQ
  It supports the following.

• -12dB to +12dB Preamp

• 10 Parametric sliders with the choice of;

• Frequency (#)hz ; 20 - 20k

• Filter Type; Peak / Low Shelf / High Shelf

• dB (#.##) ; Min: -12dB , Max +12dB

• Q factor (0.25 - 8.0)

Describe alternatives you've considered

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• More fine tuning options for "Custom Parametric EQ" to better support all possible Parametric DSP's in the future.
• Adjustable Preamp Ranges, E.g: Min Preamp = -12db \ Max Preamp = 12db
• Additional integrated preamp slider for the Parametric Optimizer to help increase dynamic range at the cost of volume or vise versa.

Additional context

Add any other context or screenshots about the feature request here.

The following Images are of the Fiio app, specifically the EQ settings for the BTR17 and any BTR1X with the PEQ feature.

There is also a website version IIRC. Here and the official fiio info guide