Introduction

Anyone remotely into the in-ear monitors world this year has seen the rise of planar magnetic IEMs, which can be attributed to the massively successful 7Hz Timeless from last year. Indeed, at the time of said review and even that of the less impressive follow up 7Hz Eternal, the audio brand had no real presence outside of China. I am happy to see there is now not only social media pages, but also active representatives on some platforms to provide more information and support on the 7Hz—also referred to as 7Hertz. This is how I first got wind of the then-upcoming 7Hz Dioko.


7Hz is barely a presence in the personal audio space and yet we now see it introduce a sub-brand called Salnotes that is intended to be a more budget-friendly solution similar to what FiiO does with Jade Audio. This is mighty confident from the Chinese brand, I think it will lead to confusion and poor branding presence across both brands now, but either way, the relevant part of the final product happens to be the Crinacle name attached to it. The Dioko, as was the case 3-4 months ago, had various semi-open and closed back versions being played around with in addition to different colors and finishes to make it a more fun looking set compared to the black coin-shaped Timeless. A week or so before it was due for launch, 7Hz contacted Crinacle to help make the Dioko a commercial success given the guy is now basically a money printer too with his IEM collaborations, and sent over physical filters/dampers and working units for him to try and get a final tuning agreed upon by both parties. It's not your typical partnership that happened over weeks, if not months, so I was curious how the 7Hz x Crinacle: Salnotes Dioko would play out. Thanks to Linsoul for providing a review sample to TechPowerUp!

Packaging and Accessories

Packaging for the 7Hz x Crinacle: Salnotes Dioko is relatively small and goes with a white base color. There's the Salnotes logo on the front too, so you can decide whether or not to call this product by all four words in the official name or simply 7Hz Dioko, as seemingly everyone has done since launch. A render of the shells is also seen on the front and back with confirmation of the collaboration on the side. Open the box to take out a large carry/storage case which contains everything else inside. I quite like the case, although it's clearly on the larger side here, with the neat incorporation of 7Hz along with the Salnotes branding on the red/yellow/black colors chosen. It's a large rectangular cuboid with a sturdy zipper mechanism that opens to reveals a soft padded compartment with the IEMs and cable snugly placed inside, and the accessories in a separate compartment above.


7Hz provides paperwork in the form of a multi-language quick start guide going over how to use IEMs and also discussing the nature of the detachable cable should this be your first time with in-ear monitors. More relevant are the provided ear tips that are additional to the ones pre-installed on the shells, of all which are seen above. The colorful silicone tips come in a variety of sizes and matching colors but seem otherwise fairly generic in fit and finish. The pre-installed size M tips, however, remind me of the AZLA SednaEarfit XELASTEC tips that came with the SeeAudio Bravery in being somewhat tacky to the touch, and lightly malleable based on a narrow temperature range, allowing them to better fit your warm ear canals.

Closer Look

The IEMs come with the cable pre-attached too, making the Dioko good to go out of the box. For a closer examination of the cables and the shells I wanted to separate them, as seen above. Simply pull out the 0.78 mm 2-pin plugs from the shells carefully without applying sideways pressure and you are good to go. Reverse the steps for use, or go with a replacement cable if you have prefer another!


I can see Dioko owners potentially thinking of getting a replacement cable that matches the face plate/shells closer in color or even simply a modular cable in case they wish to use a balanced output source. But generally, and knowing the price regime this product belongs to, I dare say the vast majority of end users will be simply using the stock cable. It's a good thing then that we get a relatively high-quality cable that does not have any issues outside of light microphonics if it rustles against the desk surface. The cable goes from a 3.5 mm single-ended connector headed to your source and is a mix of high-purity OCC (Ohno Continuous Cast) copper and silver-plated OCC copper as seen in the Litz-structure wiring employed. There are a total of 216 individual wires split into four strands that then split into two per channel at the aptly-named Dioko splitter employing metal housing as is the case throughout the cable. The other end consists of pre-formed, relatively stiff ear hooks with plastic sheathing over the cables. Each of the two strands has a 0.78 mm 2-pin connector, with L/R markings on the angled black plastic inserts here to identify the left and right channels respectively. The metal plugs all come gold-plated for oxidation resistance.


I recommend reading my 7Hz Eternal review to know more about the design of the Dioko shells which seemingly just started from where the Eternal stopped. We still get a CNC-machined aluminium alloy shell capped by a sapphire-coated tempered glass cover but now it's more egg-shaped, and without a decorative insert underneath. This means the Dioko face plates can end up looking like cheap plastic baubles in photos, but they do feel better in person I promise. Still, between the purple/blue finish and the Salnotes Dioko branding, it's way down in my list of attractive IEMs. The shells are also quite large—even more so compared to the already imposing 7Hz Timeless—and this time it's not just an extension of the face plates either. Fitting these won't be trivial, thus as we see the use of multiple vents along with an interesting angular placement of the flush cable connectors on the side. There are L/R markings here too, and removing the pre-installed ear tips shows a highly angular and stubby nozzle, which may affect fit further. There is a notch to keep the ear tips in place once installed, along with a metal grill with a finer mesh screen underneath to prevent contaminants from entering the acoustic chamber. 7Hz does not provide replacement filters with the Dioko.

Fit and Audio Performance

Seen above is the right side of the 7Hz x Crinacle: Salnotes Dioko installed in an anthropomorphic pinna that does well in showing my own experience with these. I have average-sized ears and found the pre-installed size M silicone tips to work best not just in terms of as good and secure a fit as possible from the provided options, but also provide a more balanced sound signature that fits the expected tonality. Remember that angled cable connector on the IEMs? Those help in conjunction with the angular cable housings to make for those pre-formed ear hooks to be naturally directed behind and over the ears via a simple quality-of-life tweak that I want to see adopted more. That's about the only positive thing here, since the ungainly size and shape of the Dioko shells combined with the stubby and angular nozzle makes for a less comfortable fit that most other IEMs I've tested here. Indeed, getting a secure seal with good passive isolation is also tricky, and you will have to play around with different ear tips and sizes to get these in as best as you can. Even so, I found the Dioko getting uncomfortable after 45 min or so. All this is a long way to say you need to be aware of potential fit and comfort issues here and it can be a dealbreaker for those with smaller conchas and/or ear canals. As for the driver used here, 7Hz was the first to use the now popular 14.x mm planar drivers and the Dioko continues this trend with a larger-than-Timeless 14.6 mm full-range planar magnetic driver, in addition to stronger neodymium N55 magnets on either side of the ultra-thin diaphragm. You can refer to this page for more on this driver implementation and the Dioko ends up being a power-hungry set with an average impedance of 16 Ω paired with a quite low sensitivity of 88 dB/mW. A portable DAC/amp will be a good idea thus and can give you some wireless connectivity options as well.


Testing was done similar to all other IEMs, such as the original 7Hz Timeless. Seen above is the measured frequency response for both channels of the 7Hz x Crinacle: Salnotes Dioko, which can be inspected further here if interested. Remember that last-minute collaboration I mentioned above involving filters and dampers? A lot of early production units ended up with incorrect dampers resulting in a more elevated upper mids and lower treble presence than desired. I ended up holding back on any testing thus, and told Linsoul to only ship out a representative unit after the issue was resolved. Thankfully it was caught early and affected users were taken care of appropriately, so we can talk about the Dioko's sound signature now. I'd classify it as a U-shaped set with mid-forward tuning and was also happy to see really good channel matching which is almost unheard of for these planar IEMs coming out everywhere. Crinacle's tuning preferences are also seen clearly here with a ~7 dB bass boost from 200 Hz down making for sub-bass focused energy here. Despite this, I wouldn't say the Dioko is a particularly bassy set, given I don't hear the slam that other planars provide. EQ doesn't do much either, with quantity coming only, even though I will argue the Dioko drivers are the most resolving of any I've heard in the price range it operates in.

Some of this could be the mids not being completely flat and slightly warm in the lower mids especially, but a lot of this has to do with the Dioko simply not handling layering very well. For those wanting to experience planar bass, I'd say the Dioko is not the way to go. The mid-range, on the other hand, is the strong point here courtesy of the highly detailed drivers as well as the overall tonality. Vocals are forward centric and there is plenty of range for instruments to shine through—especially snare drums and guitars. Female vocals can range from being engaging to slightly nasally, depending on your preferences. Staging isn't particularly wide here either, I'd overall say the Dioko's clarity is the main advantage it has on the technical front with even imaging being so-so. The dampers used come in handy to continue for a highly resolving and fairly enjoyable experience in the higher frequencies except with one caveat—the air region around 12-15 kHz feels quite pronounced to me, more so than the graphs suggest. This makes cymbal strikes jarring and harps feel tinny too.


To keep things short here given this is already well past the typical quick look length, I'd say the Dioko offers one of the least expensive planar IEM offerings today and thus some of the shortcomings can be overlooked. It's not as comfortable or fun as the LETSHUOER S12 or Z12, nor as engaging and punchy as the 7Hz Timeless. I'd still say the Dioko is nearly as resolving as both of these though, if not on par for all practical purposes. The real competition comes from the newcomer from TangZu Audio with the Zetian Wu (review coming soon) costing midway between the Dioko and Timeless, being tuned better than either of the others here, and also offering the best of the planar IEM experiences too. I'd probably save up for the Zetian Wu myself if you had to go for a planar IEM in 2022 rather than get the Dioko—especially with the fit and comfort issues too.


When it comes to other IEMs at/around the same price as the Dioko, we usually get single DD sets or hybrid DD/BA sets. I have here three top contenders in the form of the MOONDROP Aria (20221), the DUNU TITAN S, and the Tripowin x HBB Olina. The Olina comes close in detail retrieval but otherwise the Dioko bests them all, as well as in vocals reproduction. I'd still take the DUNU Titan S myself or even see how the newer Olina SE is that is supposed to have a more balanced treble response. These other three are also far easier to fit and listen to for longer periods of time.

The 7Hz x Crinacle: Salnotes Dioko planar IEMs can be purchased for $99 from the Linsoul web store as of the date of this article. These are going to be a love or hate affair when it comes to fit and comfort, and unfortunately marred my own experience owing to a less comfortable seating even after getting a good seal. Keep this in mind as your experience may end up fully focused on the sound signature rather than have to keep fidgeting with the IEMs after 30-45 mins as I had to. Be sure to recognize the strengths and weaknesses of the set, before making an informed decision on whether these are for you or not!