Today, Thomas reviews the I/O AUDIO SOGNO, a $399 hybrid 6 BA and dual 10mm and 6mm dynamic driver universal in-ear monitor.
Disclaimer: This sample was sent to me for my honest opinion. Headfonics is an independent website with no affiliate links or paid-for articles. I thank Shenzhen Audio for their support
Click here to read more about Shenzhen Audio products we have previously tested on Headfonics.
Note that this article follows our latest scoring guidelines which you can read in more detail here.
Earlier this year I looked at I/O’s AUDIO’s first product, the VOLARE. The gorgeous design and extensive accessory kit made strong first impressions, while the tri-brid setup and masterful tuning won me over.
The SOGNO is I/O AUDIO’s follow-up, unveiled in September 2024. At $399.00 it slots in firmly under the $599.00 VOLARE.
There is plenty of competition for the SOGNO at this price point. It makes a strong case for itself with an impressive spec sheet and driver configuration, plus the reputation of the VOLARE, but none of that matters if it doesn’t hold up in the real world.
Features
Like its more expensive sibling, the SOGNO features 3D-printed housings from experienced manufacturers HeyGears.
Inside the stunning housings, the SOGNO is a busy product. It contains both a 5-way electronic crossover and a 4-way physical crossover.
The hybrid driver configuration utilizes a 10mm dynamic featuring a silicone rubber surround with a mixed fiber dome for low and some mid frequencies, a 6mm dynamic with a PET diaphragm optimized for high frequencies, four full-range balanced armatures, along with two high-range balanced armatures.
With the SOGNO you get a modular 4-strand 6N OFC cable with silver-plated wiring. The included 3.5mm single-ended, 2.5mm balanced, and 4.4mm balanced plugs ensure compatibility with most audio sources.
The SOGNO also features an air pressure balancing system to minimize pressure in the ear and reduce fatigue. This reduced pressure also helps to protect the drivers and increase their functional lifespan.
Design
The SOGNO follows in the footsteps of its older brother with an eye-catching universal shell. Though the shape is familiar, the faceplate design and material details make it stand out.
The horizontal lines set within the smooth faceplate don’t look to be anything special. However, angle the shell and you’ll notice the trunk and branches of a leafless, Autumn tree.
Silver I and O icons can also be seen floating in the upper corners of each earpiece near the cable ports. Along with a cable-bound red O-ring that denotes the right channel, these icons help distinguish left from right.
Flipping the earphone, you find SOGNO written in gold along the rear of the shell. Ample amounts of metallic silver flakes appear and fade in visibility depending on the angle of light that hits the shell which looks phenomenal in person.
The nozzles are 6.7mm around the uppermost lip, slimming to 5.7mm around the rest of the shaft. While slightly larger than what I consider average, 5-6mm, the sizing works well for holding tips securely and is necessary to accommodate the four visible sound ports that are part of the physical crossover.
The SOGNO uses 0.78mm 2-pin ports, located on top of the shell and recessed slightly. This design is excellent, allowing the use of various 3rd party cables.
Behind the ports is a small rectangular vent. This location is an improvement over the VOLARE’s design which placed the vents in front of the ports where they were subject to interfering wind noise, something that isn’t a problem on the SOGNO.
HeyGears’ printing quality for SOGNO’s shells is outstanding, with the shell having a smooth texture across every surface. I could not locate a single fault, blemish, or seam that would detract from the print quality.
Comfort & Isolation
I/O AUDIO’s design of the SOGNO’s shell is very ergonomic, with a shapely form that naturally follows the contours of the outer ear. There are no hard edges or sharp corners to cause discomfort or hotspots, and the smooth surface feels nice against your skin.
The use of resin means the SOGNO is extremely light. Combined with excellent ergonomics, you have an earphone that can be worn for hours without discomfort.
At first glance, the shell looks the same as the VOLARE’s, but it is not as the extra drivers and updated crossovers result in a thicker shell. The only downside I experienced came in the niche situation when lying down on my side where the housing protruded more and interfered with comfort.
The bigger shell neither hurt nor helped with isolation, which is overall very good. I can use the SOGNO in noisy areas at my regular listening levels, only needing to raise the volume in the most extreme situations to counter outside noise bleeding in.
The potential for discomfort is the same as it was for the VOLARE, coming from the thick, heavy cable routing up and over the ear. The weight and girth can cause fatigue in some circumstances, especially when it’s sharing that real estate with the arms of glasses, for example.
Ear Tips
I/O AUDIO includes a wide selection of tips with the SOGNO and except for the foam set, all use high-quality silicone.
While the shafts on these tips are quite sturdy, the flanges are thin and somewhat flimsy which may lead some to seek out third-party alternatives, though I found them all perfectly functional.
The ST50 is an excellent set thanks to its good fit and tiltable shaft, similar in design to SpinFit’s various tips. It provided a great seal with a balanced sound profile and some of the deepest bass.
The ST50 also provided an excellent soundstage, on par with the TW43 wide-bore. The SOGNO already has raised upper mids and treble, aspects the TW43 boosted further and to the point of discomfort, so I avoided this set.
The TW45 medium-bore was a good all-rounder since it provided a similar low-end performance to the ST50 and didn’t boost the upper mids/treble like the TW43 wide-bore. They lacked the staging of the ST50 and TW43 though.
For the SOGNO, the TT55 small-bore was dropped in favor of another wide-bore option, the TW40. These were my preferred set since they provided the best seal, larger staging, and similar bass performance to the ST50, and the smoothest presentation in the upper mids and highs.
I’ll leave impressions of the F49 wide-bore foam tips to the community. I found them uncomfortable and itchy, like most foam tips.
As I said in my VOLARE review, this is a fantastic set of tips with plenty of variety. The only improvements I can suggest are to include multi-flange options for even more isolation or a deeper, more secure fit, and bring back a small-bore option for those who want it.
Stock Cable
I have mixed feelings about the stock cable, which is similar to the one you get with the VOLARE. It is a 4-strand, 6N OFC, silver-plated cable with a modular plug setup including 3.5mm single-ended, 2.5mm balanced, and 4.4mm balanced options.
It uses common 0.78mm 2-pin plugs, the preformed ear guides are angled well and do a good job of holding the cable in place, microphonics are minimal, a useful chin cinch is present, and it resists tangling and memory of bends fairly well. The sheath is glossy and somewhat stiff, but it’s not egregious.
The locking mechanism implementation is clumsy though, because it is threaded and requires plenty of turns to seat fully, and the collar’s prongs get stuck in the cable. Also, the pre-installed 3.5mm plug wasn’t screwed on fully out of the box because excess glue and gunk were filling the threads.
It was impossible to screw the collar down fully without feeling like I was about to break something. I had to use a small dental pick to clean out the threads, so they’d be clear enough to use fully, and even after cleaning it took a while for the threads to feel even moderately smooth.
The fit of the 2-pin plugs is nice and tight on the SOGNO, unlike my experience with the VOLARE’s cable, so that’s an improvement. Overall, it’s a good-looking cable with a great feature set but lacks refinement, which is disappointing given how good the rest of the product is.
Packaging & Accessories
Gone is the Leica-inspired layered design in favor of a large, elongated box. The exterior sheath follows the same design queues as the VOLARE’s with a dark color scheme, brand and model details on the front, with specifications and measurements on the rear.
Sliding the sheath off reveals a matte black box with SOGNO printed in glossy black. “Open” is printed in white lettering on the front flap, secured in place via magnets.
Lifting the lid, you find a cardboard insert underneath holding the manual and other extras, while another insert surrounds the carrying case, plastic boxes for the tips, box for the cable, with a cutout in the bottom left corner that is used to lift out the insert. Everything is labeled in small, white lettering.
In all you get:
- SOGNO earphones
- Faux leather carrying case
- 4-strand, 6N OFC, silver-plated cable
- 3.5mm, 2.5mm, and 4.4mm plug terminations
- TW45 medium-bore single flange tips (s/m/l) + case
- TW40 wide-bore single-flange tips (s/m/l) + case
- TW43 wide-bore single-flange tips (s/m/l) + case
- ST50 wide-bore single-flange tips (s/m/l) + case
- F49 wide-bore foam tips (s/m/l) + case
- Cleaning cloth
- Manual, warranty card, QC certificate
The case is the same one included with the VOLARE, and I was under the impression functionality was limited due to an unremovable foam insert. I was surprised when it was removed with ease from the SOGNO’s case.
I revisited the VOLARE’s case and after an unreasonable amount of force that felt like I was about to start breaking things, the insert came out. I’ll need to update this in the VOLARE review.
This is an extensive and well-thought-out accessory kit that bigger, more established brands should look to for inspiration. A secondary, smaller carrying case or cloth baggy for use outside would be a welcome addition.
Click on page 2 below for my sound impressions and recommended pairings.
