Today, we review the AFUL Cantor Flagship IEMs. The retail price is $799 USD.
Disclaimer: HifiGo provided us with the AFUL Cantor for this review. As always, I am here to share my honest and unbiased experience with the product.
AFUL
Founded in 2018, AFUL (aka AFUL Acoustics) began its journey with an expert acoustics team dedicated to advancing audio technology. In Chinese, it translates to “致音,” which means “Ultimate Sound” or “Pinnacle of Sound.” By 2019, the team had developed prototypes with innovative circuit topology and acoustic structures with the aim of improving traditional BA designs. Through continuous technological advancement, AFUL secured three patents in 2020 and commercialized its S&E Math technology in 2021, receiving recognition from the Chinese Academy of Sciences and support from the Suzhou Municipal Government.
Today, AFUL continues to push the boundaries of micro-acoustic technology, bringing a blend of unique innovations to each of their products. Their upcoming model, the Performer 5+2, will soon be reviewed on Headfonia, so keep an eye out for that. For more information on their earlier models, you can check out my colleague Berkhan’s reviews of the Performer 8, Performer 5, and the Magic One IEMs; just click on the names to read more. If you haven’t yet seen our Aful Explorer review, I highly recommend reading it.
The Cantor
Let’s get to today’s highlight: the Cantor. It is the flagship of the Aful company, featuring 14 balanced armature drivers per side along with an intricate acoustic setup including multiple waveguides, 3D printed tubes, resonance optimizers, and the Aful’s RLC network technology that we have also seen utilized on units like Performer 5 and Performer 8.
The technologies used in Cantor are a culmination of concepts that Aful has been R&D’ing since its inception. Therefore, our expectations were high. The Cantor is available on HifiGO for $799 USD. Let’s check out the highlights and jump into the review without further ado.
Specifications & Highlights
Configuration: x14 Balanced Armature Driver (per side)
Impedance: 20Ω
Sensitivity: 106dB/mW
RLC Network Electronic Crossover
Nickel-Plated Brass Nozzle
Patented Dual-Channel Acoustic Maze
Anti-Resonance Cage and Waveguide
Direct Drive Topology Technology
Multidimensional Frequency Division Architecture
4Braid 5N OFC Cable with 2-pin 0.78mm
Cable Termination 3.5mm or 4.4mm (Not Interchangeable)
Packaging & Accessories
The AFUL Cantor comes in a box with its name written in chrome letters on the top. The front of the box features a photo of the Starry Night faceplate design, set against a simple background with small informational badges depicting the Cantor’s key acoustic concepts.
On the back, the specifications are provided in both English and Chinese. After removing the illustrated sleeve, you’re presented with a navy blue box with a leather-textured finish. Upon opening it, the first things that catch your eye are the faceplates of the earphones and a navy blue leather zippered case with the AFUL logo. The interior of the zippered case is lined with soft brown velvet, giving it a plush and luxurious feel. All the accessories that come with the Cantor are stored inside this case. These include a pliable, fabric-jacketed 4-braid cable with chrome accents, a user’s manual, a warranty card, a cleaning brush, and four plastic cases, each containing a different ear tips set.
In total, there are 12 pairs of ear tips, with each set divided into S, M, and L sizes neatly organized in individual plastic cases. Regarding the ear tip materials, apart from one set of foam tips, the rest are made from silicone. However, the wall thicknesses of the silicone tips vary, which means they could influence low-frequency reproduction differently. The bore openings are similar across the silicone tips, while the foam tips have a slightly wider mouth. A small note based on my experience: as the wall thickness of the ear tips increases, their ability to transmit lower frequencies also tends to improve. Similarly, the sound generally becomes warmer as the mouth diameter decreases, and the low frequencies feel more dense and emphasized.
I would have liked to see an interchangeable cable that includes both 3.5mm and 4.4mm connectors, especially for a flagship product. This would provide more flexibility for users who switch between different sources. Apart from that, the accessory package is looking nice and complete.
Design, Build Quality & Fit
The Aful Cantor is offered with two different faceplate designs and a single shell color. It comes in two designs named Starry Night and Marine Echo. I assume that Starry Night draws inspiration from Vincent van Gogh’s masterpiece of the same name, as this faceplate incorporates the colors and tones from the painting. Glittery gold accents merge with deep and light shades of blue, creating a cohesive design. Marine Echo, on the other hand, has a more understated aesthetic, featuring a glossy and gilded faceplate. Both faceplate designs complement the shell’s deep blue color quite harmoniously.
There are several details that catch my eye in Cantor’s design, the most unusual being a vent-like opening on the back of the earphones that resembles a dynamic driver ventilation port despite the fact that Cantor uses balanced armature drivers. Since it doesn’t have a dynamic driver, I suspect that this port is either a pressure relief vent or part of the acoustic design. Indeed, after wearing the earphones for several hours, I found Cantor’s pressure build-up management to be much better than that of a fully metal, portless earphone like the Symphonium Crimson. I wouldn’t say it’s completely absent, but it’s been optimized quite well for a shell of this size.
Since we’re on the subject of the shell, let’s dive deeper, as this is particularly important for potential buyers. Considering that the Cantor houses 14 drivers on each side, the shell is actually very well-designed. Inside, there are acoustic waveguides, which are complex structures as fine as 0.15mm, printed using high-resolution, high-precision 3D printers.
When you look at the translucent shell under bright light, you can see that there’s not even a pinhead of empty space inside. Naturally, the components that take up the most space in the shell are the woofer BAs and the acoustic waveguides.
In terms of shell size, the Cantor falls into the “L” category in my usual size comparison. To help with comparison, the shell size is slightly bigger than the Hype 10, which I classify as “ML”. For further reference, “L” is around the size of the Oriolus Monachaa, and “M” would be the Mega5EST. An example of “S” would be the Aful Explorer.
However, the shape of the nozzle makes it tricky to use with aftermarket tips. As someone who firmly believes in tip-rolling, I couldn’t resist testing a few popular ear tips, like the Divinus Velvet and Tangzu Tang Sancai. The Sancai tips felt a bit loose since the nozzle isn’t particularly wide, while the Divinus tips didn’t allow the Cantor to be inserted as deeply as Aful recommends. This shallow insertion caused an increase in shoutiness around 5kHz to 8kHz, making the Cantor sound brighter and more aggressive than with the stock tips. Eventually, I had to give in and revert to the included tips, shushing the tip-rolling monster living within the depths of my audiophile soul.
Fit is a bit of a mixed bag, primarily due to the nozzle’s eccentric shape. The Cantor needs a deep insertion to sound its best, so using the included tips to achieve a solid, deep seal is essential. Aful suggests aligning the nozzle’s end with the tip of the metal tube for the optimal listening experience, and I found this advice spot-on. Without this depth, you’ll encounter the same shoutiness I mentioned above.
For context, I have large ears with a wide and deep concha and a sizable outer canal, so I rarely run into fit issues with larger IEMs. However, if you struggle with fitting flagship models from ThieAudio, you might find the Cantor’s fit similarly challenging. It’s a big monitor. Despite the size, the passive isolation is excellent, and I could wear the Cantor comfortably for long periods of time. I had no issues with Cantor’s fit during my time with it. I am still wearing it as I am typing these words, and it’s been 7 hours of non-stop work without any discomfort. Thanks, genetics, I guess.
I also found that SpinFit tips work reasonably well with the Cantor, but keep in mind that sound may vary based on your ear canal’s shape. SpinFits typically bump up the lower treble for me, which isn’t ideal, but they could be a solid option for those who like SpinFit’s fit and sound. In terms of sound, they performed better than the Divinus and other ear tips I tested, thanks to a similar stem design to the stock tips, which allows the brass nozzle to sit flush at the top.
Ultimately, I suggest experimenting, but the stock tips offer a good variety with four types to choose from, so you’re likely to find a comfortable fit among them. I genuinely appreciate the design of the Cantor. Aful has managed to pack a remarkable amount of intricate components into a shell that not only looks elegant but also feels well-made.
The review continues on the next page. Click here or use the jump below.
Page 1: AFUL, Cantor IEMs, Packaging & Accessories, Build, Design & Fit
Page 2: Sound Impressions & Technology Inside, Comparison, Last Words