Ultimate Sound 3Driver Custom In Ear Monitor – US3D Review

As I’ve  been telling before, I was aiming for this review for a while now. One year ago I found out about a very interesting Romanian company here in Bucharest named Ultimate Sound that makes custom in ear monitors.

I’ve also met the owner, Cristi Voicu, who is also the main tech guy and he struck me as a very promising and smart  man. I’ve also seen him work and he is very meticulous, thorough and very clean in doing his job.

Before starting Ultimate Sound he gained a lot of experience as a hearing aid engineer and medical equipment engineer but also from attending lots of training and courses. He’s also got a Master’s degree engineering, and to be more precise in materials for medical equipment.

I’m telling you, this guy knows what he’s doing!

Ultimate Sound US3D Ciem Review


Since I’ve first met him he made quite an image here in Romania as many known singers and professionals use his products on a daily basis. Ultimate Sound gathered an impressive portfolio in quite a short time.


Ultimate Sound has 3 custom in ears models to offer us with one driver, 2 drivers and of course 3 drivers. I will review the flagship, meaning the 3 drivers model, the US3D.

Ultimate Sound US3D Custom In Ear Monitors - Review 02

Of course, being custom in ears I had to go through the normal process, meaning that I went to their office where they took molds after my ears. Everything went very smooth and it was a pleasure talking with the staff.

You can also get your hearing tested for free with a full audiometry test and if any complications are found, there’s also an ENT Medical Cabinet right there in the same building where you can investigate the problem right there on the spot.

So all of these happen in the same  building with Ultimate Sound’s office, making it real convenient as you don’t have to make separate trips in different places and this can save a lot of your time.

All the staff is very friendly and make you feel comfortable during the stay. Cristi, the owner of Ultimate Sound invites you inside his office where you can have a coffee, listen to some music on his old school sound system or just talk about this hobby.

Ultimate Sound US3D Ciem Review 5845.

Ultimate Sound US3D Ciem Review 006

Ultimate Sound US3D Ciem Review 08

Ultimate Sound US3D Ciem Review 7

After they have your ear prints, it takes a few days to get your headphones. I’ve got mine in 5 days, sooner than I expected. Any other modifications or adjustments are to the headphones after this point are free. They also have 1 year warranty.

If you feel that the headphones don’t fit properly, I advise you in being honest about this. If you aren’t and leave them like that, you won’t get the most out of them. If your ear prints were correct, and they would most certainly be, the adjustments / modifications would be easy and can be done on the spot by adding some varnish and in a few minutes in the UV Lamp box they will be like new:

Ultimate Sound US3D Ciem Review3

Or, they could need a little polishing which would also be easy to achieve:

Ultimate Sound US3D Ciem Review4

When I received my headphones I was pleasantly surprised too see that I’ve received a free bonus, a special and very nice custom artwork on each headphone which made them quite eye catchy. One of them has the logo of HeadMania!

So, yes, you can get custom imprints on your headphones. And while we’re speaking about that I will show you the headphones of a very known singer in Romania, Andra Maruta, which were made like this on her request:

Ultimate Sound US3D Ciem Review 6

I was happy to see that Tiberiu Albu, last year’s Romania’s Voice contest winner, but also my favorite from the contest, chose to use Ultimate Sound headphones.

There are many known singers from Romania that have Ultimate Sound custom in ears. Another example would be Calin, from Voltaj.

The list doesn’t stop there, and you can find all of the artists who use Ultimate Sound  right here.

Besides the good looks and sturdy build quality, they also have a detachable cable which can come in quite useful and lets you choose from a large variety of cables on the market.

So the US3D have 3 armature drivers, each handling a different part of the frequency spectrum. Two of them are handling the bass section while the other handles the midrange and the treble.

Ultimate Sound US3D Ciem Review0

I was really impressed to see that Ultimate Sound made their  own measuring box for the headphones, built with sound isolation and everything you need to get accurate measurements.

Ultimate Sound US3D Ciem Review 5



Sensitivity : 124 dB SPL/mW at 1kHz
Frequency Response : 20 Hz – 18 kHz
Impedance: 17 Ω @ 1kHz
Acoustic isolation: 25 ~26 dB depending on the ear canal.

Their travel case is quite sturdy and comes with a cleaning brush and a manual which explains how to use them and how to care for them.

We also have a video of the manufacturing process:

Ultimate Sound US3D Custom In Ear Monitors - Review 6

Ultimate Sound US3D Ciem Review 4



Tests and Listening Experience

The tests were performed with FiiO X5, FiiO E12A, MSB Analog Dac, Ultimate Sound US3D.

These headphones are very efficient and are very easy to drive but they do benefit quite a lot and scale with better gear.

The Civil Wars – I’ve got this friend

The voices on these headphones are excellent. They are right there with you, well textured and very present but also with good, natural and very pleasant tonality. I was very pleased with both female and male voices.

The Choir of Westminster Abbey

It was a real pleasure going through this album with the USD3d. I never expected such holography from them, and I’ve also been very impressed with the positioning of each voice in the quire. I’ve found them to have a very natural soundstage with very good width and depth, quite astonishing for in ear headphones. Besides this, the voices were superbly presented into the scene with excellent / natural tonality, presence and extension.

Renaud Garcia – Marcevol

I’ve learned that I can enjoy any type of music with these headphones. The instruments sounded wonderful, showing very good details but also tactility and extension and all of this with a natural tone and a spacious soundstage.

Hugh Laurie – Six Cold Feet

I just love the guitars on these headphones as they sound very tactile, sparkly and detailed, leading to a very pleasant sensation that tickle my audiophile needs. The voice is as you expect by now, wonderfully presented into the scene. The drums hit hards and extends quite nicely. The trumpet was another joyful experience as it was very textured and nicely extended.

Infected Mushroom  – Mambacore

Let’s see how the US3D can handle slam. After headbanging on the song a few times I came to the conclusion that the slam is high with us3d ! Indeed, they have a very strong and powerful attack, followed by quick and fast decay. The bass hits hard, is very controlled and has good depth but I wouldn’t mind a little more extension. Overall they surely offered a very engaging and energetic experience!

Handel: Concerto Grosso, Op. 6: No. 2 in F Major

I’ve never enjoyed classical music so much with in ears until now, not even with IE800 wich were lovely on clasical music but had the midrange too recessed to really shine. I just love the details, the natural tone of the instruments, the big and holographic soundstage.

Ultimate Sound US3D Custom In Ear Monitors - Review 7



The bass hits hard and fast, presenting very good control and punch. The depth is good but I wouldn’t mind more extension to add more meat on the bones.


This is where these headphones really shine. The midrange on US3D is truly superb as it’s one of the best I’ve heard on in ears and I’m going to boldly say that in all headphones (tonality wise). It is impressive from details, natural tonality to presence and textures.


The treble is quite sparkly and well extended on US3D. I don’t find them bright at all, but the details on the treble are quite nice!


I love both female and male voices with US3D. Their tonality is exemplary, presenting very good presence, textures and extension. Sometimes I really feel that the singer is in the room with me.


The transients are very good. The attack is explosive and punchy while the decay is laser fast. Some may want a more lingering decay like you can find in many dynamic drivers, but I kind of like the speed and tactility the transients on US3D offer.


The soundstage is impressive, especially for in ears. It presents itself in a natural manner with good depth and width but also in a very holographic manner. Combined with some other qualities like details, imaging, natural tonality the USD3D are also great with classical music and I find myself not getting enough of it with these headphones. This is a very important aspect for me as I’ve rarely managed to enjoy classical music on in ears and US3D is certainly up for this job and even more.

Imaging/Instrument Separation

Even on crowded passages the US3D managed to perform very well, presenting very good layering and instrument separation. The fast transients and large soundstage help here as well.


The details are another strong point of these headphones being capable of extracting lots of details from the songs. They are quite analytical and they won’t mask bad recordings. Don’t get me wrong here, they are naturally detailed, they don’t throw details in your face, they come naturally.


I found these headphones to be neutral and indeed they could be very useful for professionals because of this.

Natural Tonality

Another thing that I must punctuate is that the US3D sounde very natural to my ears. All instruments and voices have a pleasant and very natural tonality, one of the best I’ve heard!

Compared to other headphones

I didn’t have anything here for a direct comparison but I can say that they are the first in ears that I truly enjoyed with every type of music. Besides them, the IE800 were very nice, especially the model I’ve reviewed, but the later versions I’ve listened to had the midrange too recessed for my taste. I can safely say that I enjoy the US3D more!

I’ve also listened to many offerings from other companies present at Canjam this year and compared them to my US3D at the show.  I must say that they sound very good indeed, even when compared to more expensive products from bigger companies!

While I didn’t have much time with Shure 846 which did have some things that I liked more than on US3d, mostly related to the bass section which was more extended and detailed on the shures, I liked US3d more overall . US3D presented a bigger and more holographical soundstage, better imaging, details and a more neutral sound signature.

Ultimate Sound US3D Custom In Ear Monitors - Review 01


The US3D  will follow me in many journeys from now on! Audiophile quality inside my pocket! I am proud of Ultimate Sound and what they managed to achieve with these headphones.

Needless to say that I am more than curious to listen to their new upcoming model the US4D that will have 4 armature drivers: 2 woofer like drivers for bass, one big driver for the midrange and one for the treble.



  • Punchy, well controlled and fast bass
  • Excellent midrange
  • Good and well extended treble
  • Excellent voices
  • Fast and explosive transients
  • Expansive and holographical soundstage
  • Very good imaging and instrument separation
  • Natural tonality
  • Neutral sound signature
  • Very Good details
  • Good build quality and looks
  • Good price/performance ratio


  • The bass would use a little more depth
  • Some may want a more lingering decay usually found in dynamic drivers, but it is a case of taste here