FATfreq X Effect Audio - Quantum (Ex-Demo Unit)

In-Ears With Planar Magnetic Driver

Sale price₹ 44,999 Regular priceMRP: ₹ 79,999
Sold out
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Why FATfrequency is Special

🇸🇬

Designed in Singapore

🥊 Young Maverick Brand

New on the scene, but bringing seasoned expertise 🌟!


I get excited about young maverick brands because they often bring fresh perspectives and cutting-edge innovation that challenge established players. These companies combine youthful energy with serious technical expertise, often demonstrating remarkable attention to detail and commitment to pushing boundaries. Think of them like startup tech companies - they might be newer, but they're hungry to prove themselves and often deliver incredible value.


Drawing on deep industry expertise and passion for audio excellence, these brands often demonstrate remarkable attention to detail and commitment to technological advancement. They frequently deliver cutting-edge technology and performance that rivals established competitors 🚀.


When you see "🥊 Young Maverick Brand" products, expect innovative excellence from companies that combine fresh energy with serious technical expertise to deliver impressive results.

🌟 Specialist

A masterpiece from experts who know audio inside and out 🔧!


I tend to describe specialist manufacturers as "audio artisans" who focus exclusively on perfecting specific categories of equipment. These products are meticulously crafted by dedicated experts who possess deep knowledge of sound reproduction, ensuring every technical aspect is refined to perfection. Think of them like master craftsmen who spend their entire careers perfecting one specific skill - their focused expertise shows in every detail.


These dedicated experts bring years of specialised knowledge to the design process, resulting in products that consistently achieve exceptional performance standards through focused engineering excellence 🎯.


When you see "🌟 Specialist" products, expect focused expertise from manufacturers who dedicate their entire efforts to perfecting specific audio equipment categories.

🦩

Boutique Brand

🐣

Born in 2016

Why we love this IEM

👑 I Am Worth It

For the most passionate audiophiles who demand nothing less than audio perfection 💎, these exceptional products represent the absolute pinnacle of sound reproduction technology. When I designate something in this category, it means we've identified something truly extraordinary - a piece of equipment that transcends conventional standards of excellence. Think of these as the Rolls-Royce of audio - masterpieces that don't simply meet expectations but establish entirely new benchmarks for what's possible.


These aren't just premium products; they're timeless investments in musical excellence whose value transcends ordinary performance metrics. Each represents a fundamental redefinition of what's achievable in sound reproduction, incorporating innovations and craftsmanship that justify their exclusive status.


When you see "👑 I Am Worth It" products, understand that you're experiencing audio perfection - these masterpieces cater to those who recognise that true excellence knows no compromise.

🦈 Serious Audiophiles Only

For those who have ventured deep into high-fidelity audio 🎯, the pursuit of sonic excellence becomes an endless journey of discovery and refinement. I believe that serious audiophiles demand equipment that can satisfy the most exacting standards and deliver performance that pushes boundaries. These products represent the pinnacle of acoustic engineering, incorporating advanced technologies and meticulous craftsmanship that enable them to reproduce music with utmost fidelity.


Each product has undergone rigorous evaluation to ensure it delivers exceptional performance that discerning listeners demand, from precise frequency response to impeccable detail retrieval and sophisticated sound staging. These devices incorporate premium components and engineering excellence that justify their position at the apex of audio performance.


When you encounter "🦈 Serious Audiophiles Only" products, expect uncompromising performance that satisfies the most demanding requirements and elevates critical listening to new heights.

🔧 Tweak & Tune the Sound

Why settle for a fixed sound signature when you can shape your audio experience exactly to your preferences 🎛️?


I love products that put you in the driver's seat of your audio journey. These specialised headphones come equipped with sophisticated, customisable tuning capabilities that let you adjust every aspect of the frequency spectrum. Think of it like having a personal audio chef who can adjust the recipe to your exact taste - more bass for your workout playlist, clearer mids for podcasts, or sparkling highs for classical music.


The adjustable sound signature means you can fine-tune bass response, adjust midrange clarity, or enhance treble detail. Whether you prefer deep bass frequencies, crystal-clear midrange presence, or pristine high-frequency detail, these solutions put you in complete control of your sound 🎚️.


When you encounter "🔧 Tweak & Tune the Sound" products, expect complete sonic customisation that adapts perfectly to your unique listening preferences across different genres.

⚖️

4.4mm Balanced Plug

🔌 Upgradeable Cable

Not satisfied with the current cable? No problem 🔧!


I believe in giving you complete freedom to customise your listening experience. These IEMs feature detachable cable systems that let you swap, upgrade, or replace cables whenever you want. Think of it like having a modular smartphone - you can upgrade individual components without replacing the whole device. Whether you're looking to improve sound quality, try different materials, or simply replace a worn cable, the choice is entirely yours.


The standardised upgradeable cable connection ensures compatibility with a wide range of aftermarket cables, giving you access to different sound characteristics and build qualities. This modular approach means your IEMs can evolve with your audio journey, allowing for easy maintenance and personalisation.


When you spot "🔌 Upgradeable Cable" products, expect future flexibility and the freedom to customise your audio experience through cable upgrades and replacements.

Why it Sounds Amazing

🔈 Planar Magnetic Driver

I love describing planar magnetic drivers as the Formula 1 cars of headphone tech. Unlike traditional dynamic drivers, planar magnetic drivers use an ultra-thin diaphragm suspended between magnets that pushes air with unmatched speed and precision. The result? Sound that’s exceptionally clean, fast, and rich in detail across the entire frequency range. 🎧


Now here’s what’s actually happening: because of the evenly distributed magnetic force across the diaphragm, you get lower distortion, tighter bass, and a superior transient response. Planars often need more amplification and are typically found in larger headphones, but the payoff is a sound that’s smooth yet revealing—incredibly accurate without being clinical. It’s the kind of driver that makes you rethink what your favorite track actually sounds like.

⚖️ Balanced Sound Signature

In my experience, a balanced sound signature is like a well-cooked meal—nothing overpowering, everything in harmony. If you’re someone who listens to a bit of everything—rock one day, jazz the next—this is the tuning I’d recommend. It doesn’t boost any part of the sound unnaturally, so what you hear is often how the artist intended it. 🎧


Here’s what’s actually happening: the headphones don’t favour bass, mids, or treble excessively. This results in a neutral, natural, and versatile sound that suits a wide variety of music genres. While it may not feel as “exciting” as some more coloured tunings, balanced headphones tend to offer the most accurate reproduction, making them a favourite among audiophiles and studio pros alike.

😳 Ultra-Wide Sound Stage

Do you wish to bring the concert hall to your ears 🏛️?


I love describing ultra-wide soundstage as "audio magic" that creates a breathtaking three-dimensional environment around your head. These specialised headphones feature an exceptionally spacious soundstage that creates the illusion you're sitting in the sweet spot of a magnificent performance venue. Think of it like teleportation technology for your ears - suddenly you're not wearing headphones, you're sitting in Carnegie Hall with perfect acoustics.


The precise instrument placement and remarkable sense of space work together to transport you directly into the music, making you feel as though you're experiencing a live performance. This creates a listening experience that's grand, enveloping, and incredibly detailed 🎭.


When you encounter "😳 Ultra-Wide Soundstage" products, expect concert hall acoustics that make you forget you're wearing headphones through sheer spaciousness and realism.

🍿 Crisp Vocals & Instruments

Vocals and instruments sound so good, it's like a warm hug 🤗!


I believe that when vocals are reproduced correctly, they should feel like the artist is performing right there with you. These headphones demonstrate exceptional prowess in reproducing clear, articulate vocals and instruments, with each element rendered in stunning detail and separation. Think of it like having front-row seats to an intimate acoustic performance where every breath, every string resonance, every subtle inflection comes through perfectly.


The natural timbre and tonal accuracy create an engaging presentation where every nuance is preserved while maintaining fatigue-free listening. Each word, note, and subtle inflection is reproduced with outstanding definition and emotional connection 🎤.


When you encounter "🍿 Crisp Vocals & Instruments" products, expect vocal excellence that brings you closer to the emotional heart of every performance.

💣 Thick Bass / Kickass Bass

When I say kickass bass, I’m talking about bass that slaps you right in the face—in the best way possible. It’s that visceral, chest-thumping low-end that makes you feel like you’re in the front row of a concert or a nightclub. If you’re into hip-hop, EDM, Bollywood beats, or anything with a deep groove, this is where the fun begins. 🔊💥


Here’s what’s going on technically: the low-frequency range is heavily emphasised, resulting in powerful sub-bass rumble and impactful mid-bass slam. This kind of tuning brings weight, warmth, and physicality to your music. The trade-off? It might mask some midrange detail or high-frequency sparkle—but for bassheads, the emotional payoff is more than worth it.

✨ Bright & Sparkly Highs

Who says treble can't be done right ⭐?


I tend to describe these headphones as having "magical sparkle" in the high frequencies that makes cymbals shimmer and vocals shine without ever becoming harsh. These products excel in delivering pristine, crystalline high frequencies with remarkable precision and finesse. Think of it like the difference between cheap glitter and real diamonds - both sparkle, but one does it with elegance and refinement that never hurts your eyes.


The treble presentation is masterfully tuned to showcase delicate nuances in the upper register, offering brilliant and engaging listening without fatigue. Every cymbal shimmer, violin overtone, and vocal harmony is reproduced with exceptional clarity and natural brilliance ✨.


When you see "✨ Bright & Sparkly Highs" products, expect extraordinary treble clarity that discovers new layers of detail while maintaining smooth, fatigue-free listening.

🚂 Needs Amplification

I tend to say this when a headphone or DAC just doesn’t wake up unless it’s got some real juice behind it. Think of it like a sports car that needs the right kind of fuel—without enough power, it won’t go anywhere near top speed. Some gear, especially those with high impedance or low sensitivity, demands a dedicated amplifier to reach its full potential.


Here's the trade-off: these headphones or IEMs may sound underwhelming straight out of a phone or laptop, but when paired with proper gear, they transform dramatically. You get tighter bass, better control, and improved resolution.


If you’ve got a power-hungry planar or a studio-grade headphone, investing in a portable or desktop amp will unlock nuance, dynamics, and depth that you’re otherwise missing out on. ⚡

Headphone Zone Certified Demo Headphones

Our careful selection of demo headphones gives you the experience of pre-burned in headphones - at drop dead prices. We do this sale every year to clear up our existing demos and to make way for new units instead. These demo headphones have been used at our Experience Studio in Mumbai. The pictures above depict the condition of the product and also indicate the accessories available with the headphone. For any specific questions about the condition please get in touch with us! While the product itself is fully tested by our Headphone Gurus and the outer packaging may have suffered some damage.

Get The Best Deal

You may or may not get the original packaging or some accessories may be missing & because of the fact that they've been extensively used as a demo at the Experience Studio, we give a good discount compared to a new gear.

Unchanged Policies

Received a defective Demo unit? Return it under our 7 Day Replacement Guarantee Policy.
P.S. If you do not like your gear, unfortunately we will not be able to accept the return.

Pre-Burned In

Demo headphones save you the time of burning in new headphones. Typically, brand new headphones take up to weeks to fully break in and sound as good as they should. With demo headphones, you get to enjoy the best sound out of the box.

Unbiased Customer Service

We have the same Headphone Zone customer support experience for Demo Units or any products.

Consider It Vintage

Vintage products have a certain charm that cannot be put into words. Think of old, discontinued demo headphones as vintage. They have a story; they have, how-to-say, character.

Professionally Inspected

A thorough inspection means you receive a 100% working headphone with no sound output issues.

Accessories to Get you Started

1. Ares S II (4.4mm)
2. NOAH Modules
3. Fatfreq x Effect Audio black Metal Case
4. Ear Tips

An Exceptional Collaboration That Unlocks Speed, Clarity & Precision With FATfreq x Effect Audio Quantum

FATfreq collaborates with Effect Audio to create Quantum, a high-performance in-ear monitor born from over a year of rigorous R\&D and collaboration with discerning audiophiles and studio professionals. Designed for those who demand absolute precision and control, Quantum is more than just an IEM; it’s an audio instrument tailored for your ears. Featuring FATfreq’s proprietary Bass Cannon™ technology and detachable Noah modules, Quantum offers fine-tuned customisation of low-frequency response and delivers ultra-fast transients, expansive soundstage, and lifelike imaging. Its refined tuning ensures a natural midrange, extended treble, and a balanced, highly resolving sound that meets the highest industry standards.

Features Advanced Planar Driver With ResoFlow™ Acoustic System For Hi-Fi Audio

FATfreq x Effect Audio Quantum features advanced Planar Driver Technology and FATfreq’s proprietary Bass Cannon™ V2. Developed over a year of R\&D with input from audiophiles and studio professionals, Quantum delivers ultra-fast transients, expansive soundstage, and lifelike imaging. The tuning achieves a natural midrange, extended treble, and exceptional resolution. Unlike conventional planar IEMs that suffer from harsh upper-treble zing, Quantum incorporates FATfreq’s ResoFlow™ Acoustic System, combining a precision-tuned resonator with a reverse exponential horn waveguide. This innovation smooths high-frequency delivery for fatigue-free listening while preserving micro-detail and air.

Fused With Noah Module System & Other High-Quality Components For Exceptional Performance

At the heart of Quantum’s versatility is the Noah Module System, a modular acoustic interface enabling soundstage customisation. Included in the package is the SuperStage Noah Module, the same one used in FATfreq’s flagship Grand Maestro, offering breathtaking spatial accuracy and a 3D holographic soundscape. Quantum also integrates other proprietary acoustic technologies: Sonar La Trompa™, inspired by the French horn’s curvature, enhances treble tonality and gain control; and PhaseAlign™, which uses acoustic delay structures to achieve time-aligned frequency delivery for coherence across the spectrum—essential for professional use on stage and in the studio.

Comes Bundled With Ares S II cable From The Signature Series II

In collaboration with Effect Audio, Quantum comes exclusively tuned with the Ares S II cable from the Signature Series II, the world’s first 8-wire solid-core IEM cable. Constructed with Dual Variant QuantumCopper™, this handwoven cable enhances signal integrity, resulting in richer sub-lows, stronger bass impact, and alluring vocals. The cable features ConX 0.78 2-pin connectors and a 4.4mm balanced termination to maximise performance. The Batch 3 Quantum package includes the Quantum IEMs, the Ares S II cable, Noah Modules and a FATfreq x Effect Audio black metal case.

Features Advanced Planar Driver With ResoFlow™ Acoustic System For Hi-Fi Audio

FATfreq x Effect Audio Quantum features advanced Planar Driver Technology and FATfreq’s proprietary Bass Cannon™ V2. Developed over a year of R\&D with input from audiophiles and studio professionals, Quantum delivers ultra-fast transients, expansive soundstage, and lifelike imaging. The tuning achieves a natural midrange, extended treble, and exceptional resolution. Unlike conventional planar IEMs that suffer from harsh upper-treble zing, Quantum incorporates FATfreq’s ResoFlow™ Acoustic System, combining a precision-tuned resonator with a reverse exponential horn waveguide. This innovation smooths high-frequency delivery for fatigue-free listening while preserving micro-detail and air.

Fused With Noah Module System & Other High-Quality Components For Exceptional Performance

At the heart of Quantum’s versatility is the Noah Module System, a modular acoustic interface enabling soundstage customisation. Included in the package is the SuperStage Noah Module, the same one used in FATfreq’s flagship Grand Maestro, offering breathtaking spatial accuracy and a 3D holographic soundscape. Quantum also integrates other proprietary acoustic technologies: Sonar La Trompa™, inspired by the French horn’s curvature, enhances treble tonality and gain control; and PhaseAlign™, which uses acoustic delay structures to achieve time-aligned frequency delivery for coherence across the spectrum—essential for professional use on stage and in the studio.

Comes Bundled With Ares S II cable From The Signature Series II

In collaboration with Effect Audio, Quantum comes exclusively tuned with the Ares S II cable from the Signature Series II, the world’s first 8-wire solid-core IEM cable. Constructed with Dual Variant QuantumCopper™, this handwoven cable enhances signal integrity, resulting in richer sub-lows, stronger bass impact, and alluring vocals. The cable features ConX 0.78 2-pin connectors and a 4.4mm balanced termination to maximise performance. The Batch 3 Quantum package includes the Quantum IEMs, the Ares S II cable, Noah Modules and a FATfreq x Effect Audio black metal case.

ConX 2-Pin Connector

FATfreq x Effect Audio Quantum features a ConX 2-pin 0.78mm connector for seamless compatibility.

4.4mm Termination

FATfreq x Effect Audio Quantum equips a 4.4mm balanced termination to connect with various audiophile-grade devices.


Box Contents
1. FATfreq X Effect Audio Quantum (Demo Unit)
2. Ares S II (4.4mm)
3. NOAH Modules
4. FATfreq x Effect Audio Black Metal Case
5. Ear Tips
Warranty
3 Months
Driver
Planar Magnetic Driver
Plug
4.4mm (Balanced)
Connector
ConX 0.78 2-pin
Microphone
Without Mic


3 Months Warranty

Don't sweat it, this FATfreq X Effect Audio - Quantum (Ex-Demo Unit) comes with a 3 Months warranty from FATfrequency that covers manufacturing defects. All products featured on Headphone Zone are backed by an original manufacturer's warranty.

Read more about FATfrequency's warranty in India.

Singapore’s Exceptional Sounding IEM Innovators

Founded in 2016 by engineers Aaron and Ben, FATfreq started as a specialist in IEM repairs and modifications, quickly earning a reputation for their deep technical knowledge across over 20 major IEM brands. Based in Singapore, the company has since evolved into the country’s fastest-growing in-ear monitor manufacturer, delivering meticulously hand-tuned, high-quality IEMs. With a focus on innovation and affordability, FATfreq serves musicians and audiophiles with a range of sound signatures tailored to diverse listening needs.

Fun Fact: FATfreq is renowned for developing Asia’s first subwoofer IEM system, bringing visceral bass response to stage performers and bassheads alike, earning them a cult following in the region.

Explore Collection
Quantum is the king of versatility in FATfreq's lineup, and is a precise, accurate IEM with massive low end impact, custom module tuning options, an upgrade cable out of the box, and a unique build that could be a great fit in anyone's IEM collection.
With its absolutely coherent and precise reproduction, the Quantum is perhaps the IEM for anyone looking for their endgame in this price range!

Other Details


Generic Name Headphone
Importer Details Importers Name: Ferrari Video
Address: 63/18, 1st Main Road, Gandhi Nagar, Chennai - 600020
Contact No: 044-24420733
Net Quantity 1
Manufacturer Details Name: Fatfreq Pte. Ltd
Address: 29A Mosque Street, S059507
Package Contents FATfreq X Effect Audio Quantum (Demo Unit)
Ares S II (4.4mm)
NOAH Modules
Fatfreq x Effect Audio Black Metal Case
Ear Tips


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