OLLO S4X Reference Over The Ear - Reviews
Pros: Light for a wood design, comfortable for long listening, lovely faux leather maybe better than sheepskin? beautiful real wood, neutral sound, no bloat, not sibilant, natural curve nearly flat, for sound engineers more than casual listening, very little break in required, good fit, band is auto adjustable and I love it, price for performance is outstanding, excellent with lower power mobile devices (true to source of course)
Cons: wire is light but a little too light for excessive use I would think, they are too neutral perfect (is that a con or a pro?) , they can not play excessively loud (you probably shouldn't do that anyway - not healthy for your ears)

OLLO S4X Studio Reference For Serious Recording?

"Flat out of the box. Neutral and brutally honest." is what the company from Ollo claim for their top of their range over the ear open back headphone. I had to try it for myself- I purchased this pair myself- and am glad for it. I am way over and very tired of the $500 or less Bose, Sony, Audio-Technica , AKG, SHURE, Beats By Dre or is it Apple now? Master Dynamic (although I like their sound/ love their construction (MH30) on ear hp for the price), SkullCandy, Marley headphones, JBL, etc... why am I over it? I don't like mass produced poor sounding factory made junk- $500 is a lot of loot! I want it all- hand made gorgeous wood with amazing measurable performance- I am done with wasting $400 here (you hear?) or $500 here.


I am a huge fan of Etymotic ER4p/s and have found few over the ears that can compete with their brutal honest sound production. It's not that I am into S&M but I can tolerate some honest sound reproduction when I seriously listen- especially when I mix professional videos for my clients- be it for a real DEA story of high crime and corruption (The Last Narc or Rouge Narc) or mixing videos and sound for Grammy award winners like Anglea Hunte. If I am filming Michael K Williams for an interview - I can not afford for my sound engineer or for me when monitoring the shoot to fail- there are no second re-takes. When I set up the mics on location, be it a lavalier, shotgun or supercardioid and set the levels on the external recorder - I can not afford a mistake. Everything needs to be done right the first time.

OK-enough on that- back to the well made OLLO Wooden reference S4X headphones (they were just released in 2020) with super comfy velour and better than leather feeling ear pads (really you have to feel them to know what I am talking about)- do I like them for at home use when I mix at the console? Yes. Would I use them out in the field- yes and no- They are not closed backs- so on set you sometimes get bleed and reverb from headphones back in to the mics- so be careful. If you use them on location- be aware. Also you will hear things around you and they will hear your track- this is of every open back and is a normal thing to be expected.

How do they sound? They sound neutral- exactly what the doctor ordered - you get your medicine for the cure here. Don't expect bloat or excessive treble if there is none on the recording- if you want excitement look else where- these can be eq'd and will take a slight bump up in eq nicely if that's your thing (they are very easy to drive too and work very well with phone type connectors (3.5mm) etc if thats what you want- imagine wearing professional ear phones on the train or plane or at the beach (after Covid 19 is over) and people starting a conversation about them - they are remarkable looking on and off- but you can't expect these headphones to do the "rocking of your world" thing unless you do eq em. Low power amps or internal phone amps should drive these fine- just expect to hear the quality of the amp/dac and music. So its possible for these to do both worlds perfectly- just know what you are getting here- these are precision tools designed for professionals at the mixing board- and that they do very very well. Vocals are very precise- if your actor or singer is terrible or over-modulating - expect to hear it and fix it quickly before continuing- that's what these headphones do exceeding well. They pay off in dividends by making the music mix sound as honest as it should be or not. If your old headphones interject too much bass (like so many on the market for mass appeal sake do) your mix will sound weightless and if your vocals sound too high pitched- how can you correct that if you don't know it in the first place? These headphone may just make you more money as a professional because the final mix will sound good (theoretically) on everything be it speakers, car stereo or headphones (the good ones and the bad ones). And if you are not making money at mixing professional tracks, that's ok, it might just make you a better listener of what sounds well recorded and what sounds off- you will be more picky when selecting a poor MP3 song vs a FLAC song. Got a DAC you need to hear how it really sounds? OLLO. Got some new crazy cable you want to test out? Get the OLLO S4X and you more than likely will hear the difference. Did you just get to your friends house to compare equipment? The OLLO s4x should be in your bag.

Please take note: I did read/listened to some reviews of the other models by OLLO headphones and they were not designed to be as precise as the latests version of the s4x I had bought for myself- so do not think or get confussed here please! I am not refering to all OLLO headphones- just the s4x I am reviewing - I never heard the other OLLO's so I can't talk about what I haven't heard or base my opinion on other peoples reviews. I will say the other reviews got me to buy these and try them for myself. I will never take the word from other people or reviewers as a way for me to explain what I personally hear- they may guide me- but I make the decision after hearing for myself what to think, as I think you should too. The money back guarantee is what sealed the deal for me- that tells me the company OLLO is so confident in their product - that you have no risk. I like that and frown on any company who doesn't offer such a deal- especially internet sales when in person try outs are not possible. Do they really expect me to take a risk and get stuck if I don't like them? Those other companies must be crazy.

I love the cuteness of these wooden headphones compared to my larger wooden Kennerton Magni's or Gjhallahorns- but those cost twice as much (and worth it btw)- in the sense they are heavier in actual weight (lbs) and in actual sound- my Kennertons go down deeper and extend higher - reveal more dynamics at lower and higher sound levels and reveal micro dynamics unheard of even by reference headphones like the Sennheiser HD600. I digress - these Ollos are easy to get the mix right and don't need to be playing at ear splitting levels to do their job.

When your headphones need to be a precision scalpel for sculpting or paint brush for painting the perfect musical portrait for your signer artist, actor, film or production house- the OLLO S4X finally have done it- they are brutally honest as their web site says- they are a tool and have a place in any collectors box of headphones if you want to know what nearly ruler flat headphones sound like with your music. I truly think these are an amazing feat of engineering that we as consumers have been craving for a long long time. You would have had to pay $1000+ for that years ago and even then they were not flat like these OLLO's are - and thanks to OLLO we don't need to pay any where close to that bounty- hand made craftsmanship anyone would be proud to have in their collection. They are truly quality.

The Warranty is an unheard of 5 years! I forgot to mention the box they came in is recyclable and earth friendly- some people could call it a cheap looking box- I call it practical. They also supply a faux leather bag with draw string to store your OLLO's or cables in.

The included wire is a bit light duty but that could be a good thing- they use a 2.5mm in the cup and a 3.5mm jack and 6.35mm (1.4") adapter. I seen one video by OLLO where the owner talks to other sound engineers about the cable being removable and not a permanently attached type that are seen on so many other headphones which are supposedly made for professionals- which could break in busy environments like a studio by pulling down the whole unit off a desk or whatever and break the headphones- where by the breakway type conectors will just disconnect saving the fall of entire unit. I also like the idea that you can upgrade the cable when ever you want or if in time with everyday use, owners can replace the cable if it shorts out from wear and tear.

About the 30 day period- They write: "We know it's difficult to make an educated decision based on tech specs and reviews. The only true way to know if it's for you is to try it out. 30 days money back, no questions." Every single on line company should offer this for their products and if they aren't they should be after they read this.

Ollo Ref Pic1.jpg

Price For OLLO S4X Headphone is 399,00€ or $449.065 US Dollars at the time of this review.
Well worth it if you crave reference sound in a hand made headphone. You will not be sorry and the value here is extraordinary. They even send you a graph with your exact headphones as they were each individually tested (the graph is in the box when you receive them- insuring the flat frequency response for both left and right ears- truly remarkable in every way!

I am not here to sell headphones or make any money from recommending these by the way- I am being honest and sincere- if you are tired of the same old box store type offerings then you will find a home for these precision tools of the trade- music for me is what makes the world go around (that and NASA's explaination found here These headphones are necessary for people who want to hear the truth. Can you handle the truth?


John Massaria
Headphone user, music lover and professional video and audio producer
I wasn't paid by OLLO - I bought these with my own $ - so honesty for me is the best policy!
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John Massaria
John Massaria
2 very different headphones- Sennheiser HD600 is glorious w/ OTL (Crack sb) amps - a dirt cheap end game solution. The S4X by Ollo is not euphoric at all- it's a tool for assessing music or equipment not designed to enjoy a sit down for long casual listening but it could make you a better listener by paying attention to details- its nearly ruler flat+non emotional. It's a great headphone to have in a collection because of its sheer uniqueness to do precise evaluations. It is a simple genius. Like a computer crunching numbers - very precise but -
John Massaria
John Massaria
I hope this helps understand
Translated, thank you.