Free worldwide shipping Free FedEx Priority over USD 250 Handmade in Singapore since 2008

Epsilon MKIII Premium Upgrade Cable for Headphone | IEM

Epsilon is a UPOCC copper upgrade cable for headphones and IEMs, with 126 strands per wire and 504 per cable in a Litz 5 configuration. Tuned by AAW engineers for sensitive IEMs, it brings clarity across the spectrum, a rich mid-range and textured bass, in a...

  • UPOCC copper
  • Litz 5
  • 504 strands
  • 23 AWG
  • Tuned with AAW
Bass9.1Mids9.3Treble8.9Stage8.9Detail8.9
Configure your cable

Choose your earphone connector and options below.

  • Built to orderShips in about 1 week
  • 14-day returnsStandard builds · conditions apply
  • 1-year warrantyOn every cable
  • Handmade in SingaporeChat and phone support

Loading cable options…

The late boomer.

Epsilon

The late boomer.

UPOCC copper in a Litz 5 configuration, with clarity across the spectrum, a rich mid-range and textured bass. Tuned by AAW engineers.

  • 504 Strands per cable, Litz 5
  • 126 Strands per wire
  • 23 AWG Wire gauge
  • 24 g Weight
Litz 5 UPOCC Copper

Construction

Litz 5 UPOCC Copper

Copper conductors in UPOCC cast, 126 strands per wire and 504 strands per cable in a Litz 5 configuration, for low resistance and unimpeded signal transmission.

The result is clarity across the spectrum, a rich mid-range and textured bass.

IEM Matching

Tuned with AAW

Precision-tuned by AAW engineers for sensitive IEMs, for a cohesive, synergistic sound with minimal phase distortion. It carries the AAW badge.

Stage and Street

Stage and Street

A lightweight build with a sleek black insulating sleeve, at home on stage and in daily use.

Epsilon is a UPOCC copper upgrade cable for headphones and IEMs, with 126 strands per wire and 504 per cable in a Litz 5 configuration. Tuned by AAW engineers for sensitive IEMs, it brings clarity across the spectrum, a rich mid-range and textured bass, in a lightweight, yellowing-resistant black sleeve.

Sound Guide

How Epsilon rates for treble, mids, bass, bass depth, imaging, headroom and detail retrieval. Use it to match the cable to your earphones and source.

Ratings are Null Audio’s listening notes, out of 10.

  1. Treble 8.9 out of 10
  2. Mid 9.3 out of 10
  3. Bass 9.1 out of 10
  4. Bass Depth 8.9 out of 10
  5. Imaging 8.9 out of 10
  6. Headroom 9.1 out of 10
  7. Detail Retrieval 8.9 out of 10
Ready for daily carry

In the box

Ready for daily carry

  • Epsilon cable Your length and connector
  • Premium leather pouch For daily carry

Craft and care

Introducing FlexiPlug

Introducing FlexiPlug

The FlexiPlug is a multi-connection system, enabling users to switch to adequate connectors for their IEMs.

Currently supporting 2PIN, IE300, A2DC, IPX, Pentaconn Ears and QDC 2PIN.

Build Note

Build Note

Designed, handcrafted and shipped from Singapore.

Built-to-order. Lead time around 1 week.

Ear guide (~10cm) is installed by default for commonly used IEM connectors (e.g. 2PIN, MMCX, IPX). Let us know if your IEM/headphone is modified or needs extra customization.

Anti-Yellowing

Made to Last

Epsilon’s black insulating sleeve is made for prolonged durability and resists yellowing, so the cable keeps its look on stage and in daily use.

Caring for Your Cable

Care

Caring for Your Cable

Coil it loosely in large loops and keep it in the included leather pouch when you’re on the move.

Unplug by holding the connector, not the cable, and avoid sharp bends right at the plugs.

Wipe it with a soft, dry cloth, and keep it away from solvents and alcohol-based cleaners.

Every cable has a 1-year warranty. If anything goes wrong, contact us and we’ll take care of it.

Specifications

Technical details

Cable
Conductor Material
UPOCC Copper
Wiring
23 AWG
Length
1.2 m standard; any length from 50 cm to 3 m in 2 cm steps in the configurator
Weight
~24g
Connector Color
Gunmetal (NL5 hardware)
Solder
WBT Silver Solder
Pin contact
High precision fabrication, 24k gold plated
Protection
Black insulating sleeve, yellowing-resistant
Compatibility
Earphone and headphone connectors
FlexiPlug (switchable 2-pin, IE300, A2DC, IPX, Pentaconn Ear, QDC 2-pin), 2-pin 0.78 mm, Flat 2-pin 0.78 mm, MMCX, A2DC, IPX, A2DC (headphones), Etymotic ER4P / ER4B / ER4S, Etymotic ER4SR / ER4XR, FitEar, JH Audio (with bass control), Sony IER-Z1R, Sony MDR-EX1000, Sony XBA-A / XBA-Z series, Ultimate Ears TripleFi 10, UE / UM / QDC legacy 2-pin, KZ C-pin 0.75 mm 2-pin, KZ / 64 Audio 0.75 mm flat 2-pin, Beyerdynamic T1 / T5p, Focal Utopia, Sennheiser IE 40 PRO, Sennheiser IE 8 / IE 80, Sennheiser IE 300 / IE 600 / IE 900, Sennheiser IE 500 PRO, Sennheiser HD 59X, Sennheiser HD 600 / HD 650, Sennheiser HD 700, Sennheiser HD 800, Mini XLR 3-pin, Mini XLR 4-pin, Shure SRH1540 / SRH1840
Player plugs
2.5 mm balanced, 3.5 mm, 3.5 mm right-angle, 3.5 mm balanced, 4.4 mm balanced, 3-pin XLR (pair), 4-pin XLR, Lightning DAC, USB-C DAC (Realtek ALC5686), USB-C DAC (ESS ES9280C)
Service
Warranty
1 year
Returns
Standard builds: 14 days from delivery, unused and in original packaging; 30% restocking fee, shipping not refunded. Custom spec, length or connector builds: no change-of-mind returns once production starts. Defects are covered by the warranty.
Made in
Singapore, built to order

Find the right connector for your earphones

Customer reviews

Rated 4.9 out of 5 from 40 reviews.

  • 5 out of 5 · A**x · 2026-03-24

    Good Upgrade Cable for IE600

    I purchased this cable to replace stock IE600 cable. It is a cable with better built quality compared to the stock one. Sound clarity improve by a bit.

  • 5 out of 5 · Low · 2025-12-29

    Quality Cable

    Love the weight and thickness of the cable. Improved the sound quality as well—fantastic customer service, responsive and accommodating. Area to improve - punch. Too small. Can't fit my IEM.

  • 5 out of 5 · Darren · 2025-12-16

    Great Quality

    Great quality upgrade to my stock cables, feels and look great, and incredibly quick shipping!

  • 5 out of 5 · Michael Y. · 2025-06-01

    Amazing Quality

    I've been using this cable for over a month and I'm happy with my purchase

  • 5 out of 5 · K. Z. · 2025-05-19

    Nice upgrade for my Z06

    Compared to stock cable of Z06, the 8-wire version of Epsilon gives a good upgrade while not changing the original sound signature.

  • 5 out of 5 · Ivan · 2024-12-08

    Incredible Cable

    I have cables that cost several hundreds of dollars and they pale in comparison to this. It is incredibly well made. Shipping was fast, too. Null Audio is going to be one of my go-to cable manufacturers going forward.

  • 5 stars: 37 (93%)
  • 4 stars: 2 (5%)
  • 3 stars: 0 (0%)
  • 2 stars: 0 (0%)
  • 1 star: 1 (3%)
R
Ronie S. (Sunshine Coast, AU)
Very Satisfied

I bought it for my Symphonium Titan to replace the stock IEM cable and the results are really good. I have placed my second order for my Dunu Da Vinci.

S
Stanley T.Q. (Victoria, CA)
Null Audio Epsilon

Got this cable for my 64Audio U4s, as flat 2-pin cables are not very common (most companies only ship cables with standard recessed 2-pin connectors, which look funky when paired with 64Audio's protruding socket assembly). The cable itself is relatively well-built, although the injection-molded plastic around the y-split does have some bit of fraying, and the plug does have a small, shallow dent. The wires itself are pliable, soft, and don't tangle. The ear hook itself is quite thick, but still comfortable. The fit and feel of this cable is significantly better than 64Audio's stock cables, which actually cost more (retail).

Sound wise, the U4s is definitely better than 64Audio's stock "Premium" cable (SPC material). It has a slightly poofier bass response, with more meat, but less control. The mids are relatively the same. And the treble is slightly more laid back, in that it kills some of the brightness/harshness the U4s, and many other tia-equipped 64Audio UIEMs I've heard. In general, it makes the U4s more palatable for my tastes.

The most surprising thing is that this sub-200 USD cable ships with a personalized card that has the owner's name hand-signed upon and a grey leather case, something lots of other boutique cable companies fail to do, especially with their entry-level products.

c
chen J. (Toronto, CA)
You won't regret it

The cable connection is significantly better than factory original, and it rests comfortably around ears. Most importantly, my IE600 now sounds amazing.

J
Ji H.Y. (Gwangjin-gu, KR)
Highly recommended

Both the build quality and sound quality of the product are excellent. It upgrades the ie900 without compromising its character. It is lightweight and suitable for outdoor use. Highly recommended.

A
A**x (Singapore, SG)
Good Upgrade Cable for IE600

I purchased this cable to replace stock IE600 cable. It is a cable with better built quality compared to the stock one. Sound clarity improve by a bit.

L
Low (Singapore, SG)
Quality Cable

Love the weight and thickness of the cable. Improved the sound quality as well—fantastic customer service, responsive and accommodating.
Area to improve - punch. Too small. Can't fit my IEM.

D
Darren (Singapore, SG)
Great Quality

Great quality upgrade to my stock cables, feels and look great, and incredibly quick shipping!

M
Michael Y. (North York, CA)
Amazing Quality

I've been using this cable for over a month and I'm happy with my purchase

K
K. Z. (Shanghai, CN)
Nice upgrade for my Z06

Compared to stock cable of Z06, the 8-wire version of Epsilon gives a good upgrade while not changing the original sound signature.

I
Ivan (Rancho Cordova, US)
Incredible Cable

I have cables that cost several hundreds of dollars and they pale in comparison to this. It is incredibly well made. Shipping was fast, too.

Null Audio is going to be one of my go-to cable manufacturers going forward.

B
Bruno F. (Luxembourg, LU)
Amazing cables

Great looks, top quality and most importantly a noticeable improvement in sound quality.

M
Max H. (Vancouver, CA)
Great cable

My favorite cable ever. Nice and lightweight, and built super well. Highly recommended!

R
R W.C. (London, GB)
Epsilon MkII

I thought that my ThieAudio Monarch MkII IEMs deserved something better than the somewhat microphonic stock cable. As I had already benn delighted by my purchase of a Brevity for my Sennheiser IE600s, I plunged for the higher spec Epsilon. Good decision. Warm, enveloping sound with great comfort and ease of use.

K
Kyle K. (New Albany, US)
Very Good

I love these cables. This one is slightly warmer than my last Ethos which is what I was looking for. Really nice build and it is in black which is what I wanted.

N
Nico S. (Singen, DE)
Amazing Quality&Service

The cable looks and feels amazing. Customer service for a custom length was also a very pleasant experience. Bought it for my IE900 the connectors fit perfectly. I can only recommend this !

Y
Yiyang H. (Vancouver, CA)
Great build quility and looking

Bought it for my IE900. Best cable ever used so far. Building quility is super solid. Very premium looking with the new designing. Sound is fantastic. Definitlity will recommand to others.

A
Alexis S. (Vevey, CH)
Beautiful product

I bought the Epsilon Series Premium Upgrade Cable for my Hifiman Aryas. The packaging and cable is top notch. The only issue is how they fit, leaving a 1cm gap between the connector piece and the headphone. This doesn't seem to affect sound, but it is a little strange and unexpected.

T
TATSUYA T. (Yachiyo, JP)
worth the money

Null Audio won't fail you.

F
Florin P. (La Seyne-sur-Mer, FR)
Epsilon Series Premium Upgrade Cable for Headphone

Hello, first of all, thank you very much for your work! All redy IEM Sennheiser IE900 it's amazing IEM and now with your cable, every thing i'ts fabulous! Thank you again. I will buy a Epsilon balanced 4.4mm for IE900 soon.

C
Christopher F. (Dallas, US)
IE 600 Upgrade cable

This is by far the best upgrade cable for the IE600, the fit, size and sound quality are perfect.

G
G.K. (Atlanta, US)
Absolutte Must have for IE600

I was on the fence of returning the IE600 due to its absolutely lackluster performance from the headphone cable. No product should be that faulty. My friend convinced me to give them another go but to buy a null audio cable. Not only is the connection now solid and dependable, but the sound signature is everything I was expecting when I bought them in the first place. Cable construction is better than anything I have purchased, they are comfortable, high quality, and really fantastic across the board. Any more high end IEMs I buy, the first place I'm next is to build a cable through this website. 100% worth it!

P
Perinkolam A.G. (Singapore, SG)
Epsilon Series Premium Upgrade Cable

Great cable. No microphonics or memory and sound stage is wider too.

M
Martin T. (Clementi Housing Estate, SG)
Epsilon Series Premium Upgrade Cable

It bring warm to my IE600 especially for jazz music.

M
Mark B. (Los Angeles, US)
Above and beyond

Build quality top notch.

G
Graham A. (Los Angeles, US)
USB-C cable clicking

Purchased this cable with a USB-C DAC (ESS9280) and the cable has clicks and pops when using with usb-c devices. Seems to be defective, looking to get a replacement but support has been slow to respond and resolve the issue.

J
Jason A. (Brisbane, AU)
Null cable

Awesome!

S
SweetySugar

The photo is of the mk2, but the title is mk3. Which is right?

Null Audio

Epsilon is now the MKIII and the photos are being updated; you receive the current version.

Questions

Good to know

How long until it ships?

Every Epsilon is built to order by hand in Singapore. Lead time is around 1 week.

Will it fit my earphones?

Choose your connector when you order. FlexiPlug lets you switch between 2PIN, IE300, A2DC, IPX, Pentaconn Ears and QDC 2PIN. If your earphones are modified or need a custom fit, contact us before ordering.

Find the right connector for your earphones

Can I get a different length?

Yes. Choose Cable length in the configurator above: set any length from 50 cm to 3 m in 2 cm steps. Up to the standard 1.2 m costs nothing extra; longer cables cost more, and the price is shown before you add to cart.

For a length over 3 m, contact us or WhatsApp +65-8731-5476.

Will the sleeve turn yellow over time?

Epsilon’s black insulating sleeve is made for prolonged durability and yellowing resistance.

What is the return policy?

Standard builds can be returned within 14 days of confirmed delivery if unused and in their original packaging. Change-of-mind returns carry a 30% restocking fee, and shipping is not refunded.

Custom spec, length or connector builds cannot be returned for a change of mind once production starts. Faults are a different matter: every cable has a 1-year warranty, so contact support@null-audio.com and we will assess it.

Read the full return policy