If you're looking for a decently priced well built IEM with good slam and physicality down low, a clear articulate and accurate midrange and treble with smooth delivery then it's hard not to recommend to add the OH1 to the list of IEMs to seriously consider. If you can spare the 59€ extra their CTU-01 balanced cable is strong value and a superb match to the OH1 to take it one setp further and frankly with a SQ punching above its price point.
- Clear, articulate and transparent midrange with very good separation and a surprisingly accurate tone
- Female vocals are beautifully portrayed
- Good sub bass extension provides physicality
- Good tight mid bass slam with snappy attack and quick decay
- Clear and smooth treble with fairly accurate tone providing excellent realism
- Excellent build quality, punches above its price point
- Affordable CTU-01 upgrade cable with superb build and superb synergy with the OH1
- Bass tips really don’t do justice to the OH1, I would stay away from them!
Packaging and accessories
The Ikko OH1 comes with a superb packaging featuring nice art piece, a rare sight at this price point.
The box feature a premium quality cardboard with a nice tray system and the unboxing is a real treat and suprise at this price point. The package contains the OH1 along with a soft leather carry pouch and two sets of tips one is “bass” focused (blue) and the other “balanced” (gray).
Fit, Build & Isolation
Consistent with the packaging quality, the Ikko OH1 features a shell made of aerospace alloy with only 6 grams per side the OH1 are very lightweight. The anodized painting is superb and the overall finish is quite premium and unexpected at this price point. Competition should take notes!
The fit is shallow but very good once you’ve found the right tips and secure thanks to preformed earhooks and the fact the cable is lightweight. The stock cable is a small gauge 4 strands of 8 high-purity oxygen-free copper plated (OFC) silver-plated cable. It has very good build and is lightweight and quickly forgotten, with no microphonics.
The CTU-01 upgrade cable is a silver plated cable but this time is an OCC build with 127um high purity single crystal copper silver-plated core with ultra-low cable impedance which Ikko says maximizes the transient performance. I was impressed by the build and as we’ll see it’s very much worth spending an extra 59$ as we’ll see further in the review.
Ikko Audio is a relatively new brand that started in 2018 and quickly made a name for themselves with well thought out designs and coherent tunings. Recently they launch two very well received portable DAC/amplifiers with IKKO Zerda ITM03 and ITM05. I have never auditioned any of their IEM so I was thrilled at the opportunity to review both the OH1 and OH10 as well as their very nice CTU-01 upgrade cable to check how both OH1 and OH10 would scale with a balanced upgrade.
The OH1 is a hybrid featuring a 10mm polymer composite titanium coated dynamic driver along with a Knowles 33518 balance armature driver. The OH1 features an alloy sound cavity while the OH10 as we’ll see in our next review, features a copper cavity.
The OH1 is a fairly balanced IEM aside from its emphasized bass presence it packs a suprisingly clear, articulate and accurate midrange and treble with a smooth delivery. Soundstage is balanced and quite good expansion in all directions with good imaging.
Note : The following impressions are based on the gray “balanced” tips as I found the “bass” blue tips to be too bassy with too much bass presence and less control. Your mileage may vary.
The OH1 features good sub bass extension and very good presence with good control, the dynamic certainly delivers a welcome physicality that was expected from a modern hybrid. I enjoyed my usual test tracks, both Sohn’s “Falling” and Aphex twins “Ageispolis” were highly enjoyable with the OH1.
The OH1 mid bass is spot on to my ears with less presence than the sub bass it stills packs good slam with very good control. It has a quite snappy attack and quick decay with good speed for a 10mm dynamic. There is moderate texture and detail but I am nitpicking here given the price bracket this is quite good performance.
I switched to the CTU-01 upgrade cable balanced again out of DX160 and I found the sub bass extension was a tad better with also better presence and control. The mids bass is tighter and more impactful with a bit more detail as well.
The OH1 midrange is clear, articulate and transparent with very good separation and a surprisingly accurate tone. I honestly didn’t expect this from an IEM in this price range. There is just a slight warmth infused by the bass prominence relative to the mids and the OH1 is just slightly north of neutral (keep in mind I am still writing with the balanced tips on, bass tips do tilt the balance to much more bass presence and less mids clarity).
The lower mids are spot on to my ears with no emphasis or dip and the instruments have good body but it’s not a thick midrange. Separation is very good and the midrange is very articulate and the OH1 is able to handle complex passages with larger ensemble. Instruments timbre is accurate making for a very realistic presentation. The upper mids have good bite providing excellent clarity although the tuning is on the safer side avoiding any sensitive area there.
Vocals are just slightly forward and very clear. Sibilance is a non issue with the OH1 and female vocals are engaging and convey good emotion. A very strong performance in the price bracket.
Switching over to the CTU-01 upgrade cable was very interesting as it affects the OH1 midrange very positively : separation is significantly better and I hear both fuller lower mids instruments have more body and better bite in the upper section. It’s a more engaging and lively midrange with more satisfying body and a lifelike presentation. Impressive. Vocals are a bit more forward and I hear more nuances in interpretation making for a more engaging listen. Overall the better treble presence with the CTU-01 as we’ll see also comes into play tilting the overall signature towards a more balanced presentation where bass is balanced by upper mids and treble presence.
The OH1 treble are clear and smooth with again a fairly accurate tone with excellent realism.
Lower treble has just enough energy to be engaging but treble heads will lack the treble bite that can be so satisfying when going to the limit. The flipside is that the OH1 is a non fatiguing IEM. Upper treble is well extended and there is good air with smooth delivery which feels very natural.
Switch over to the CTU-01 balanced upgrade cable and things are quite different : There is more lower treble energy with excellent bite, making for a more energetic and engaging treble while retaining it’s smooth delivery. There is also more air which is beneficial to a much better soundstage and more precise imaging. This cable brings the best out of the OH1 IMHO.
The entry segment is not the easiest for a manufacturer to stand out as there are so many options around it’s actually near impossible to comprehensively compare every option. This being said, Ikko stands out right away with the OH1 premium packaging, impeccable build and accessories. There is a clear attention to detail that spells quality and it’s furthered by how well tuned and refined the OH1 is for its price. You wouldn’t figure Ikko is a relatively new brand but rather a seasoned one.
If you’re looking for a decently priced well built IEM with good slam and physicality down low, a clear articulate and accurate midrange and treble with smooth delivery then it’s hard not to recommend to add the OH1 to the list of IEMs to seriously consider. If you can spare the 59€ extra their CTU-01 balanced cable is strong value and a superb match to the OH1 to take it one setp further and frankly with a SQ punching above its price point.
I spent approximately 20 hours with the Ikko OH1, listening on iBasso DX160 and Lotoo PAW S1 using the stock and upgrade CTU-01 cable balanced.
Thanks to Ikko for providing a review unit of the OH1 as well as the CTU-01 upgrade cable. As usual, this review is my honest opinion. No incentive was given for a favorable review.
- Leather carry pouch
- Stock SPC OFC cable braided 4 wires
- Set of S,M, L balanced and bass tips
- sensitivity: 106 dB
- frequency range 20-40kHZ
- Impedance 18 ohms
- 5.7mm nozzle