Reference Pro Custom IEM - FATFreq

Reference Pro Custom IEM

Sale price$699.00
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Reference Pro offers textbook, reference-grade detail, and separation via three precision-tuned balanced armature drivers for the accuracy demanded while monitoring and mixing. The perfect tool for producers and singer-instrumentalists seeking to bring their mixes to the next level.

Express Shipping

All international orders will be shipped using DHL express.

Express Shipping

All international orders will be shipped using DHL express.


1 Year Limited Warranty included for IEMs.


1 Year Limited Warranty included for IEMs.

step by step guide:

how to order?

1. Start an Order

Go to our Custom-fit IEM page and click on the ‘Order Now’ button for your chosen IEM model.


Developed by FATfreq in Singapore

3D Contour Fit

A secure fit allows you to get the best out of your in-ear monitors. Using software and earmold retention principles, FATfreq digitizes your scans to shape important pressure points, ensuring your perfect 3D-fit. Models are then sent to our high-precision 3D printers for fabrication.

Linear Impedance

FATfreq uses proprietary circuits to correct the non-linear impedances of multi-driver systems. The different output impedances across all your devices cause frequency response to vary. Having this tech ensures consistency in frequency response for all our IEMs when plugged into any device - Be it your mic-pack, mixer board, phone or dedicated DAP.

Sonar La Trompa™

Inspired by the anatomy of the traditional french horn, FATfreq uses exponential horn curvature for gain control and to improve treble tonality via acoustics. Providing you with Smooth, natural sounding highs, grounded by a nice timbre in the mid and low frequencies.


The absence of a DSP in IEMs means that we have to match the phase of multi-way systems via Acoustic delay. Using proprietary structures, we were able to align the low, mid and high frequencies such that they reach your eardrum in a coherent manner. Giving you the sound accuracy and resolution demanded on stage and studio.

In The Box

- IEMs
- 4-Core Silver Plated Copper (SPC) Cable with 3.5mm Audio Jack
- Fatfreq Hard Case 
- S/M/L Silicone Eartips
- IEM Cleaning Tool
- 1 Year Warranty

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