
S4X REFERENCE HEADPHONES
Designed and measured using IEC 60318-1 standard.
Neutral and brutally honest.
€399,00
I WANT ONE NOW
RESEARCH & DEVELOPMENT
REFERENCE SOUND
Natural response achieved using the power of acoustics design and audio engineering, not a single line of code.
Designed and measured using IEC 60318-1 standard.
HANDPICKED COMPONENTS
MATCHED SPEAKERS
We measure all speakers in every series and match them together to achieve minimal possible tolerance between left and right channel.
• Neodymium
• 2 layered coil
• PET membrane 25u


POWERED by SATTI
HIGH PRECISION WOVEN MESH
Designed and manufactured to improve acoustics and protect sensitive components.
• Smooth monofilament fiber
• Efficient protection from dust, metal particles and liquids
• Strict airflow control
CUSTOM DESIGNED
EARPADS
They fit around your head snugly but provide enough padding to rest comfortably against your ears
• Outer diameter: 90 mm
• Inner diameter: 55mm
• Hybrid velvet
• Pleather
• Memory foam

TECHNICAL SPECIFICATIONS
Frequency range:
Impedance:
smart devices ready
Weight:
HOW DO THEY SOUND?
We measured and compared the frequency responses of the main mixing headphones on the market, so you can get a visual representation of the S4X's sound.

NATURAL FEEL
PREMIUM MATERIALS
Timelessness of stainless steel coupled with luxury nautical leather and velour for maximum comfort. Paired with a smell of a fresh sustainably sourced wood.
AWARDED BY EXPERTS
GERMAN DESIGN AWARD winner
The German Design Award is the international leading prize of the German Design Council. Their goal is to discover, showcase and recognize unique design trends.
We are proud to be declared a winner in the electronics category.


NATURAL COMFORT
EAR FATIGUE NO MORE
Custom designed velour earpads fit around your ears snugly while the self-adjusting strap provides for a perfect fit. Combined with a balanced sound, it will enable you to work on headphones for hours.

WE'VE GOT YOUR BACK
5 YEARS LIMITED WARRANTY
We trust our products and we build them to last. Our 5 year warranty program is a testament to our commitment to quality.
QUALITY CONTROL
WE MEASURE EVERY PAIR
OLLO headphones are individually tested and measured and come with the frequency response measurements chart in the package.


DETACHABLE
2000 MM CABLE
You can easily exchange a cable with a new one in case it breaks or even buy some other cable design if you prefer. Just unplug and replace.
• dual 2.5mm TRS and 3.5mm TRS
• 6.3mm adapter
• connector: 3.5mm jack with an adapter to 6.3mm jack
DESIGNED FOR PRO USERS
SERVICEABLE AND UPGRADEABLE
Every headphones's part can be purchased in our store and replaced with home tools.
Moreover, we are on a mission to offer our customers the possibility of at least one upgrade per model.
"I love my S4X reference headphones: they sound fantastic, are reliable and trustworthy, sit comfortably on my head and around my ears, don't give me ear-fatigue and don't press my ear onto the glasses allowing for continued and comfortable use.”
- MARC URSELLI
[U2, Foo Fighters, Nick Cave, Lou Reed, Sting, Keith Richards]
"The separation between the instruments, the dynamic and stereo image is perfect to be comfortable to mix with them.
I was amazed by the S4. But I am floored by the S4X!
Truly amazing."
- WILLIAM ROBERTSON
[Mick Jagger, Nicki Minaj, Will.I.Am]

TRY BEFORE YOU DECIDE
You have 30 days to try it, use it, and love it — if you don’t fall in love by that time, reach out to our team to initiate an easy return and refund process.

5 YEARS LIMITED WARRANTY
We trust our products and we build them to last. Our 5 year warranty program is a testament to our commitment to quality.

PAY IN PAYPAL INSTALMENTS
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