Custom Art FIBAE 7 Unlimited Review

Today we’re checking out Custom Art’s newest creation: The Custom Art FIBAE 7 Unlimited IEM. Its price is €1.500 Euro.


Disclaimer: The Custom Art FIBAE 7 Unlimited was sent to us free of charge in exchange for our honest opinion in this review. The monitor is a universal one and doesn’t need to be returned.

About Custom Art

It’s been some time since we reviewed a Custom Art IEM, but here we are again. For those of you who are new to custom in-ear monitors, we’ll do a short intro: Custom Art is a Polish-based company that was founded in May 2012 by Piotr Granicki. Piotr was a reviewer at the time he started his own company and with the experience he had, he was convinced he could make great-sounding monitors.

Our Polish friends in the beginning probably were mostly known for their flagship model called “Harmony 8.2” but they have been really busy and with the FIBAE series and the successful Massdrop IEM, they have gotten very popular, very quickly. We’ve covered the original Harmony Pro, the Harmony 8.2 and several of the FIBAE IEMS of Custom Art’s product line-up.

When they first started Custom Art was only making custom in-ears, but now they offer both universals and customs.

What is FIBAE?

If you’re not familiar yet with the FIBAE system, keep reading. If you already know what it’s all about, go to the FIBAE 7U chapter below. (This part is taken from a previous review).

So what exactly is FIBAE and does it stand for anything? FIBAE is the abbreviation of Flat Impedance Balanced Armature Earphone and it’s the world’s first In-Ear Monitor design providing flat impedance and phase. By changing the Balanced Armature driver character from inductive to resistive Custom Art solved one of the oldest problems in the industry – dependence on the output impedance of the sound source for correct earphone output. With FIBAE™ technology your earphones will always perform best from any DAP.

So basically it means that the FIBAE monitors in theory will sound almost the same no matter what DAP, phone or amplifier you use. You can find the full information on the FIBAE technology right here on CA’s page and there’s also a dedicated FIBAE thread on Head-Fi. Piotr tells us the following:

In early 2016 we stumbled across an interesting occurrence during work on IEM designs, which prompted us to investigate possible applications for In-Ear Monitoring. We discovered that our design resulted in nearly flat impedance and electrical phase plot of a Balanced Armature driver, reducing dramatically the load for audio amplifiers and providing a near-identical response (either frequency or CSD) when switching between sound sources with substantial difference in output impedance. At that moment FIBAE technology was born. In mid-2016 we filed for an international patent on our Flat Impedance driver.

FIBAE 7 Unlimited

The FIBAE product line-up has seriously been extended, and you nowadays have a FIBAE 3×3, FIBAE 4, FIBAE 6 and FIBAE 7 Unlimited. How impressive is that! The one we’re looking at today is the FIBAE 7 Unlimited, the reference model of the FIBAE series for now.

Lieven reviewed the original FIBAE 7 model in 2019, in the custom form, below:

The FIBAE 7 Unlimited is available in both a universal and a custom version, the former being like our review sample. The FIBAE 7U’s dedicated web page can be found here:

FIBAE 7 was first created to celebrate 7 years of the Custom Art brand. The IEM came as their co-flagship, next to the well-renowned Harmony 8.2. FIBAE 7 incorporates driver modules from across their IEM range to create the most balanced, the most natural and the most exciting IEM they have done so far.

The Unlimited version that we review today, is a result of the feedback from the community who had a chance to test or use the original FIBAE 7. What Custom Art tells us is that; they reduced the mid-range emphasis to making it less vocal-forward, added more sub-bass for more impact, and improved the high-frequency range with a 3D printed waveguide and an advanced crossover.

It is an epitome of natural sound, delivering even frequency response with immense details without fatigue. We are unlocking the potential of FIBAE 7 and removing all the limits!


– Dual Sub-Low, single Low-Mid, dual Mid-High, single proprietary High, single proprietary Super High
– Two Top-Firing Balanced Armature Drivers
– Flat Impedance technology
– 122 dB @1kHz @0.1V
– 12 Ohm @1kHz (+-1.7 Ohm 10Hz-20kHz)
– 10Hz-21000Hz (+-20dB into IEC 60318-4 coupler)
– Null Audio Arete OCC Copper cable
– Custom or Universal Fit

Page 2: Packaging, Build Quality & Comfort, Cable, Sound
Page 3: More on Sound Quality
Page 4: Comparisons & Conclusion

4.4/5 - (78 votes)

A keen audiophile and hobby photographer, Berkhan is after absolute perfection. Whether it is a full-frame camera or a custom in-ear, his standpoint persists. He tries to keep his photography enthusiasm at the same level as audio. Sometimes photography wins, sometimes his love for music takes over and he puts that camera aside. Simplistic expressions of sound in his reviews are the way to go for him. He enjoys a fine single malt along with his favourite Jazz recordings.


  • Reply August 27, 2022


    Very nice review, if I would a technical iem like 7u, but a bit more warm and mid-bass oriented what can I look at?

  • Reply August 29, 2022


    Lime Ears Pneuma would be a good choice.

  • Reply September 14, 2022


    Thank you very much for reply, and pneuma was on my mind too, great to hear so!

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