A unique headphone experience from Sineaptic

I love a company that tries to ’think differently’ (to borrow the Steve Jobs mantra from the early days of Apple) and I believe with the SE-1 Sineaptic are that type of company.

The Audio industry is constantly seeking the next sonic innovation and trying the SE-1 was a nice discovery at a super pragmatic price. What sets these headphones apart is some ingenious design choices that Sineaptic
made that means you get an Open Back headphone with Ribbon Driver that gives you that spacious sound while no longer ’tethered’ to a specific headphone amplifier due to the clever usage of special onboard amplifier, which you can use with bluetooth or even with a provided wired cable.

There are some compromises involved but not many, so read on to find out what you can expect from the Sineaptic SE-1.

The New Retail packaging

Before receiving my SE-1, I had seen a few pictures of its packaging, some reviewers seem to talk more about the ‘crazy’ packaging than about the headphone itself.

That packaging is still available as an option when ordering and is now called ‘AirGuard’.

It is essentially a huge box with the SE-1 in a box suspended with rubber bands, it was unnecessarily, not practical and not particular good for the environment and at $350 not very good for your pocket either.

The new retail packaging is environmentally friendly and brings down the overall package cost to a mere $199 so better for everyone, but it is a much more basic experience and for those expecting premium packaging with their premium sounding headphones you might be a little disappointed but for me, it was a great option, headphones should be all about the sound and not about the packaging:

Note: the only thing you might miss with this cheaper packaging is the carrying case with still comes with the AirGuard packaging is not provided with the newer packaging, though being an open back headphone you probably won’t be using it outside your house much anyway.

Here are some photos of the packaging:
Inside that box is more cardboard holding the SE-1:	Sliding out the inside cardboard - it opens up like this:
With some branding on the back of that box:	You then you can lie it out unfolded:
A close up of the headphones in this packaging:

Overall I really appreciate this option, it doesn’t look ‘premium’ but it’s good for the environment and good for your pocket and because its very secure doesn’t affect the ‘final’ product in any way.

So, once you take everything out of the packaging you have these contents.

Build Quality and initial impressions

At first glance, you will notice a few things about the SE-1: the size yet its light weight, the unconventional headband, the extra large ear cups, and it’s plastic construction. Let’s get into these:

Headband suspension mechanism

I have seen this design on some headphones a few years ago, but it is an unusual design these days:

But it actually works well with nice comfort:

And because it just touches you head in 2 places:

This design keeps your head cool for long periods:

Given the suspension mechanism sit under the headphone, you might get some strange looks but given it’s an open back you will probably always be using it in own House or Garden. You soon forgot how large these headphones are due to its light weight construction, this I imagine is one of the reasons I think Sineaptic went with an all plastic design:

Large Ear cups

It is hard to represent the size of the ear cups in these photos, but they are both large and deep and to my specific ear shape are extremely comfortable.

Here is a size comparisonto a Hifiman Sundara to give you an idea of how much larger these ear cups are:

When I measured the size of these ear cups I got 110mm external diamter, 65mm internal diameter and very generous 25mm deep.

Clamping force

They do not provide that strong a clamping force but other than if I bend over or shake my head rapidally I never felt they would fall off. Because they are open backs the sound quality is not affected as much by having a tight clamping of the earpads on your ears. I could wear glasses easily without seen a drop in the quality or quantity of the bass, which is typically a problem.

A nice alternative use-case for these headphones

One very nice use-case for these headphones that I had not anticipated before getting them was just sitting out in the garden in the sunshine or walking around my the house, even though its open back it won’t annoy the neighbors (like for example a outside bluetooth speaker) and provides a much wider more natural audio experience than either a TWS or a bluetooth headphone outdoors.

Features

Let’s delve into some of the features of the SE-1

Bluetooth

The Sineaptic SE-1 headphones come equipped with Bluetooth 5.2, providing a stable wireless connection. Since this bluetooth version supports multipoint connectivity, you can connect the SE-1 headphones to two devices simultaneously. I found this feature is particularly useful when I was using the SE-1 when working from home as I was switching between music via my smartphone and work calls via my Macbook Pro. The SE-1’s Bluetooth performance ensures low latency and high fidelity, making it suitable for both casual listening and more demanding uses like watching movies or gaming.

Note: But the SE-1 is limited to fairly basic codecs with SBC and AAC supported, this is one of those slight compromises that Sineaptic have made with the SE-1. I imagine in a future headphone they will add LDAC and AptX-HD (or other newer bluetooth codecs).

Analog Cable

In addition to Bluetooth, the SE-1 also supports wired connections via a 3.5mm analog cable. The transition between wireless and wired modes is seamless, although users should note that there might be slight static when plugging or unplugging the cable due to the internal amplification always being active because the special class D amplifier is still required for the ribbon drivers even when using a cable.

Battery Life

The SE-1 headphones are powered by a lithium-ion battery, according to the specifications up to 8 hours of playback time at 50% volume on a full charge. I found this was pretty accurate, in fact I think I was getting up to 10 hours playback over multiple days without need a charge. Charging is facilitated through a USB-C port.

Microphone

The Sineaptic SE-1 is equipped with an integrated MEMS (Micro-Electro-Mechanical Systems) microphone. This microphone technology is known for its reliability and high-quality voice transmission, making it ideal for phone calls and voice commands. The microphone’s performance is particularly beneficial in work-from-home settings or for users who need to take calls on the go.

In my usage, I found microphone was good but not great, it was very useful for quick calls, but occasionally it faded while I was on longer calls, I think this was mainly due to the varing distances between my smartphone and the headphone during calls (it is tempting to walk around while using the SE-1).

Here is an example of the audio recorded with the microphone:

Before we get into how it sounds, let me share some of the research I made around the ribbon driver technology within the SE-1:

What is a Ribbon Driver

A ribbon driver is a type of transducer used in audio equipment to convert electrical signals into sound waves. Unlike traditional dynamic drivers, which utilize a diaphragm attached to a voice coil, ribbon drivers employ a thin, lightweight ribbon made of conductive material suspended within a magnetic field. When an electrical current passes through the ribbon, it vibrates, generating sound waves with remarkable accuracy and efficiency.

In headphone audio, there are a few ’exotic’ types of drivers that have unique properties that everyone should try to experience but these typical require specialised amplification. Of these more ’exotic’ drivers, both electrostatic and ribbon driver headphones required special hardware and were up until now only available to high-end customers who would pay maybe thousands both for the headphone and maybe another thousand for the dedicated headphone amplifier.

So when I read that Sineaptic were cleverly bringing this exotic ribbon technology to the masses I was very intrigued and being a technology nerd I was even more impressed with how they are doing this. Instead of a dedicated amplifier which typically makes these ‘ribbon driver’ headphones unportable and super expensive. Sineaptic decided to build a special class D amplifier into the headphone itself and because they did that the next logical decision was to give it a long-lasting battery and make it work over bluetooth.

This to me is a genius move, effectively solving 2 big problems with exotic high-end headphones: custom amplification and portability and then delivering this is a package that costs an incredibly pragmatic retail of $199.

But I imagine you want to know if its any good, so read on to get my opinions.

Sound quality

In summary, the SE-1 has a bass response that resonates deep and the overall sound is complemented by the intricate detail of its ribbon driver technology. While the midrange is good, but if I was being a little fussy, I would say it is a little uneven compared some planars magentic heapdhones, causing the tonality of certain songs to sound a little too forward. But this is more than made up for by the sound stage, those large drivers really shine in the width you get from these headphones, probably only better by my Hifiman Edition XS (which are two times the price).

Bass

With the SE-1 headphones, bass enthusiasts are mostly in for a treat with the SE-1 especially for an open back. For example, the pulsating bassline of Pink Floyd’s"Money" or the thunderous kick drums in Miles Davis’ “So What,” the SE-1 delivers bass with authority and precision. Each note is rendered with satisfying impact, striking the perfect balance between depth and definition. I love listening to open back headphones in my house and hearing this level of bass from an open back (with resorting to EQ) while walking around my house (and garden) is a fantastic experience.

Note: One area though where the SE-1 struggles (and where I believe Sineaptic have some room for improvement was in “bass distortion” when playing loud. I believe the internal amplifier struggled when pushed on some heavily bass tracks, for example with the bass in James Blake’s ‘Limit to your Love’ at >80dB+ levels. So, If you like playing your music very loud you may (depdending on the tracks) hear some distortion in the bass region especially. Some EQ to lower the bass significant lowered this distortion.

Midrange

With the SE-1, the midrange vocal performances are a real stand out with great clarity and emotion, songs like Norah Jones in “Don’t Know Why” or the raw emotion of Johnny Cash in “Hurt” where especially a fantastic experience with this headphone. But I noticed on some tracks the vocal and some piano pieces sounded a little muted, but this was rare as mostly the midrange is excellent.

Treble

The treble on ribbon drivers is always a joy (hence why we all love AMT tweeters) and Sineaptic have rightly tuned the SE-1 to perfection to give as much detailed as possible in this region. From the shimmering cymbals in “Hotel California” by the Eagles to the delicate strings of Vivaldi’s “The Four Seasons,” the SE-1 reveals the intricate details and harmonic overtones with remarkable precision. The ribbon driver technology ensures that every high-frequency transient is reproduced with exceptional accuracy, adding a touch of brilliance to every musical passage. I never found the SE-1 sibiliant, but I can imagine it on that fine line between providing ribbon driver “based” technicalities you might want and when that detail gets a little ‘sharp’.

Soundstage And Imaging

As I mentioned in the summary at the start of this section, I loved the soundstage of the SE-1, the extra large earpads together with the very specific tuning of the SE-1 really help to emphasise that soundstage. With tracks like “Time” from “Dark side of the Moon” by Pink Floyd or “Boléro” by Maurice Ravel I loved the instrument separation provided by soundstage of the SE-1.

But on some tracks were you would normally expect to hear some ‘depth’ to the music like “So What” by Miles Davis, I believe SE-1 was slightly let down a little by the quality of the bluetooth codec used (SBC and AAC rather than LDAC or AptX).

Specs and Measurements

Lets get into some specifications and measurements

Specifications:

The specifications of the SE-1:

Measurements:

Here are some brief measurements taken on my 711 clone coupler with my KB5010x soft ear pinna:

Frequency Response

The frequency response of the SE-1 is pretty good with a few key tweaks, the ’enhanced’ sub-bass around 40hz is well controlled and is excellent for an open back headphone. Though as you will see in the distortion measurements this boost does increase the distortion:

The 500 to 1K region is slightly elevated providing a mid-forward tuning there and the 1.5-3K dip is also typical of tuning that want to emphasize the soundstage (as you will see some Hifiman headphones also have a dip in this region). The channel matching is also pretty good.

Note: I believe Sineaptic have been quietly updating the tuning as every good audio company should and made significant improvements since the early reviews were published as this is significantly more neutral than earlier published measurements.

The Aux cable input also provides exactly the same frequency response which given it goes through the same internal amplifier this should be no surprise:

Some comparisons

So firstly I am comparing the SE-1 with some 2 classic open back dynamic drivers:

Of these the SE-1 probably needs the least EQ IMO, the HD600 definitely needs a bass boost and the AKG K702 has too much treble gain to be comfortable listening too for too long. While the SE-1 is not perfect, the 2 obvious differences you see in this comparison (the sub-bass boost and the ‘soundstage dip’ around 2K) are some of the SE-1 best audio features.

Finally, just comparing to a planar known for its soundstage, like the Hifiman Edition XS - you can see that same dip on the Hifiman but a more balanced midrange:

Distortion

As I mentioned earlier, I found at louder volumes you get more distortion ‘artifacts’ that to my ears meant I was getting a slightly ‘compressed’ digital ( i.e. ‘bluetoothy’ sound ) which is a shame, as mostly the SE-1 sounds fantastic. This was only when I played the music loud and during the brief quiet sections of songs with high dynamic range.

So this was the distortion level I measured:

Though as a % of the overall SPL the SE-1 was mostly well behaved except for the bass region:

But when pushed to 90dB levels you can see allot more distortion:

I asked Sineaptic and then mentioned they have some tweaks to reduce this on newer models, so if I get the opportunity to measure an SE-1 in future I will update this review with those newer measurements.

Rating

I have given the SE-1 a pragmatic rating of 4 stars, it is an amazing to hear what can be achieved if a company think creatively about how to deliver a unique audio package. My only complaints are really the distorion when playing load and a minor complaint about a missed opportunity in that they do not have a companion mobile application with the ability to EQ this headphone and even provide personalised EQ as that is becoming more common place with Bluetooth headphones. They removed the EQ ‘boost’ capability that they had on earlier models.

Conclusion

Only a few times in my life have I get to try a device with a unique combination of technologies and Sineptic have done a lovely job with providing the Ribbon Driver sound to the masses with the SE-1.

You get a very open soundstage, deep bass, mostly excellent tuning specifically designed to show off the capabilities of its ribbon driver, but the bluetooth codecs selection is poor and the onboard amplifier is not controlled enough for the ribbon drivers at high volumes.

But I encourage everyone to try it especially at its very pragmatic price.