If you want open-back planar headphones with a stated comfort-focused adjustable headband, choose HIFIMAN HE400SE; if you need a wider stated frequency range and a large planar driver, choose FiiO FT1. For side sleepers, neither is an obvious fit: both are over-ear, wired, open-back headphones, so their earcups may press against a pillow and they do not isolate outside noise.
HIFIMAN HE400SE vs FiiO FT1 at a Glance
• FiiO FT1: Planar magnetic drivers, a 95 × 86mm driver unit, and a stated frequency range of 20Hz–40kHz. Its stated weight is about 374g, but it is still an open-back wired headphone, not a noise-isolating option.
• Choose HE400SE if the adjustable lightweight headband, included adapter, and design claims around reduced distortion matter most to you.
• Choose FT1 if you want the larger specified planar unit and the broader stated frequency range.
• For side sleepers, both have the same basic drawback: an over-ear cup can be uncomfortable when pressed between your ear and a pillow.
The HE400SE is for someone who wants a wired, open-back planar headphone and values the design behind its driver. HIFIMAN describes its conductive layers as covering nearly the entire diaphragm, with Stealth Magnets designed to let sound waves pass through with less interference. Those are design goals aimed at reducing distortion; they do not make the headphone closed or noise-canceling.
The listed frequency range is 20Hz–20kHz, with 32-ohm impedance and 91dB sensitivity. HIFIMAN says the sensitivity makes it suitable for low-voltage sources, including portable audio players. The dual-sided cable uses a 3.5mm connection, and a 6.35mm adapter is included, which gives it a straightforward wired setup for compatible equipment.
How We Research
We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-10-09 · 6 min read · Independent comparison
The maker also highlights an adjustable lightweight headband and comfort during long listening sessions. The stated weight is 385g, so comfort is still personal, especially during a long stretch or when lying down. I would skip it if you need closed-back isolation, wireless listening, or headphones that are comfortable with your ear pressed into a pillow. Its open-back construction and over-ear fit make it a poor match for blocking surrounding sound or side sleeping.
The FT1 is aimed at listeners drawn to a large planar driver and detailed diaphragm construction. Its unit measures 95 × 86mm, and FiiO describes a 1μm PET diaphragm with sapphire and aluminum coatings. The design also uses a uniform magnetic field, which FiiO says is intended to reduce uneven diaphragm motion and distortion. These are technical design features, not a guarantee that every listener will prefer its sound.
The stated frequency range is 20Hz–40kHz, wider on paper than the HE400SE’s 20Hz–20kHz range. The FT1 is wired through a 3.5mm jack and has no noise control listed. At about 374g, it is slightly lighter than the HE400SE by the figures provided, but that small difference alone cannot establish which one will feel more comfortable on a particular head.
Choose the FT1 if its larger specified driver and broader published frequency range are the features you are seeking. Skip it if your priority is noise cancellation, a closed-back design, or sleep-friendly headphones. Like the HE400SE, it is open-back and over-ear. That means it is not the right category for someone searching for noise canceling headband headphones for side sleepers.
• Best fit for a low-voltage source, according to the stated specs → HIFIMAN HE400SE. HIFIMAN gives its sensitivity as 91dB and specifically describes it as suitable for low-voltage sources.
• Best fit if the broadest listed frequency range is your priority → FiiO FT1. Its stated range reaches 40kHz, compared with 20kHz for the HE400SE. That difference is a specification, not proof that it will sound better to you.
• Best for a supplied 6.35mm adapter → HIFIMAN HE400SE. Its package includes one alongside the 3.5mm cable.
• Best for a large, explicitly measured planar unit → FiiO FT1. FiiO specifies a 95 × 86mm driver.
• Best if you want an open-back planar design with Stealth Magnets → HIFIMAN HE400SE. Its listed features explain that magnet design as a way to reduce interference with sound waves.
• Best if you are interested in a coated ultra-thin diaphragm → FiiO FT1. Its listed construction includes a 1μm PET substrate with sapphire and aluminum coatings.
• Best for side sleeping → Neither. Both are over-ear and open-back, and the available specifications do not establish that either has a pillow-friendly profile.
• Best for an extra bass over ear headphones for side sleepers search → Neither is a clear match. The supplied details do not establish a bass-forward tuning, and the open-back design is not built to keep sound in or outside noise out.
That last distinction is worth keeping in mind. Search phrases such as “best voice assistant headphones for side sleepers” can mix several needs together, but neither product sheet lists a voice assistant feature. Both are wired headphones, and neither lists noise control. If you need a voice assistant, noise cancellation, or a comfortable fit against a pillow, these specifications do not show that either model provides those things.
The comparison is clearer if you separate listening goals from sleeping needs. Both models are open-back planar headphones intended for listening setups, not a documented solution for bed use. The HE400SE makes a more specific case for low-voltage sources and includes an adapter. The FT1 makes a stronger spec-sheet case for a large driver and an extended frequency range. Neither has enough listed information to call it the better choice for side sleepers.
I would choose the HIFIMAN HE400SE for its stated low-voltage-source compatibility, adjustable headband, and included 6.35mm adapter. The FiiO FT1 is compelling if its larger planar unit and wider published frequency range are your priorities, but I would not choose either specifically for side sleeping. For side sleepers, I’d look for a design explicitly suited to lying on a pillow rather than assume an open-back over-ear headphone will work.
Neither is a clear side-sleeping pick based on the listed details. Both are wired, open-back, over-ear headphones, and the specifications do not describe a pillow-friendly earcup design.
The FiiO FT1 is listed at 20Hz–40kHz. The HIFIMAN HE400SE is listed at 20Hz–20kHz. Those published ranges alone do not establish which headphone will sound better to an individual listener.
No noise-control feature is listed for either model. Both are open-back, so shoppers looking for noise canceling or isolation should consider a different headphone type.
Which should I choose if I want to use a portable audio player?
• Anker Soundcore vs Unremittingly mini earphones ，Mini
• Sennheiser Consumer Audio BTD vs 1Mii 5.3: APTX Adaptive
• OSALADI Gaming Headset Noise vs Mixiba 2PCS
• Wobeefuu USB C Headphones vs COOYA USB C Headphones
As an Amazon Associate I earn from qualifying purchases.
We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon and affiliated sites.
When you buy through links on this page, we may earn a commission from qualifying purchases at no extra cost to you.
Amazon and the Amazon logo are trademarks of Amazon or its affiliates. This site is an independent third-party review and is not affiliated with, endorsed by, or sponsored by Amazon or the product brands mentioned.