Super compact and comfortable shells, Nice accessory set, Big and highly resolved vocals, Well-controlled bass, Airy top-end
Treble is very fit-dependent, Minimal noise isolation, Sub-bass roll-off, Imaging could be sharper
The OH1s is a beautifully designed earphone with excellent build quality and a super svelte form factor. The sound has a unique character that will no doubt appeal to some but cannot be universally praised and recommended.
ikko is definitely a company I’ve been meaning to work with for some time. They have an alluring range of hybrid IEMs and some snazzy portable DAC/AMPs too. In particular, the company is known to offer innovative form factors with regards to both of these, and their IEMs too offer a striking abstract aesthetic. A few years back, the company released the original OH1 that originally put the company on the map. This was a dual-magnet structure Ti DD + Knowles 33518 BA hybrid monitor that many lauded for its bass performance. The OH10 released last year used the same driver setup but implemented a pure copper acoustic chamber in addition to optimising the nozzle diameter to reduce resonances and distortion. The OH1s is their latest model and another evolution of the same formula. While the BA tweeter remains unchanged, the OH1s implemented a new carbon-nanotube dynamic driver and makes all-round upgrades to the design. It has a new 3-part acoustic chamber aiming to reduce reflections, resonances and optimise phase coherence, dubbed SVAS acoustic cavity technology. This comes with a new, sleeker form factor and oval tip design.
The OH1s retails for $199 USD but is available for $139 USD at the time of writing and for the remainder of September 2021. You can read more about it and treat yourself to a unit on ikko.
I would like to thank Rebecca from ikko very much for reaching out to set up a review of the OH1s. All words are my own and there is no monetary incentive for a positive review. Despite receiving the earphones free of cost, I will attempt to be as objective as possible in my evaluation.
- Driver: 10mm CNT dynamic driver, Knowles 33518 BA
- Impedance: 32 Ohms
- Sensitivity: 109 dB
- Frequency Response: 20 Hz – 40 kHz
I was very impressed by the unboxing experience, it makes the OH1s feel far more expensive than it is. The outer sleeve has specs and anime-inspired artwork, sliding it off reveals an ikko cover that contains the hard box inside. The user is first greeted to a foam plate showcasing the earphones and exploded diagram of their design. A metal ikko pin is also provided in a very CFA-like fashion. Below is another compartment containing a lovely leather carrying case, the cable and selection of ear tips with their own plastic holder. ikko provide a flexible 5 sizes of memory foam and 5 sizes of silicone tips. Of note, the OH1s is now using proprietary oval tips similar to those seen on the Beyerdynamic Xelento. This gives them an especially comfortable and shallow fit, but also means third party tips don’t seal as well on the nozzle.
Premium build quality has always been a focus for ikko and the OH1s exemplifies this with its unique and visually distinct 3-piece construction. The alloy sound tube construction and signature rippled faceplates sandwich transparent acrylic, giving it a sleek, modern aesthetic with elegant flowing lines. The faceplates especially captivate with rich contrast and dimension, wrapping around the edges of the shell. This is a very attractive and well-constructed earphone that feels solid yet compact and ergonomic. The triangular profile adds further visual intrigue, true to ikko’s marketing they do indeed resemble gemstones in a charming fashion.
The cable attaches via regular MMCX connectors and there is no key system here making third party cable swaps simple. The stock cable is of pleasing construction and complements the earphones themselves well with its lightweight design and streamlined internal braided structure. However, it is a little springy with some memory meaning it can take some time to straighten out when initially removed from the box. Otherwise, there is little to complain about, the smoke jacket is smoother and the trifecta of conductors below give it a unique look. Metal connectors provide a premium look while well-moulded albeit strangely long ear guides aid a comfortable and stable fit.
Fit & Isolation –
If you have small ears and want a super compact earphone with a slim profile, there aren’t many better options than this. The OH1s sits alongside other outliers like the Xelento with which is shares clear inspiration. This is not a bad thing at all, like that earphone, the shells are absolutely tiny, and their rounded edges prevent hotspots entirely. In addition, they are super slim, meaning you are able to wear these while sleeping with no issue. This is aided by the unique fit style, with oval nozzles and the factory tips designed for them. They have an especially shallow fit but, in return, also wear with basically zero in-ear pressure.
This makes them exceptionally comfortable long-term, and you are quickly able to forget about them. At the same time, their lightweight and low-profile nature combined with an over-eat fit means stability also isn’t a concern. They stay put very well. The downside to all of this is passive noise isolation which is well below average. They block some sound but not much even compared to vented single-DD competitors. The open feel is something some may prefer but it does mean you will need to turn up the volume is used during daily commute. They also aren’t really viable for use in especially loud environments even using the included foam tips.