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Updated January 10, 2024·
If you prioritize sound quality, especially for music, the Thieaudio Monarch Mk II earbuds offer superior audio performance and are versatile for a range of multimedia content, including TV and video. However, they are more expensive and might not be as comfortable for everyone compared to the Sennheiser HD 400S headphones. The Sennheiser headphones provide great comfort, easier portability thanks to being foldable, and an excellent choice for gaming due to lower audio latency. Neither option supports wireless connectivity, so consider the necessity of having a cable in your activities, as well as the need for active noise canceling which neither model offers. Give Feedback
this description is based on the product variant with some specs and product variant with some specs. At the time of writing, the variant with some specs cost some dollars and the variant with some specs cost some dollars.
Advantages of the Sennheiser HD 400S
Very good for phone calls
Very good for gaming
Good for air travel
Advantages of the Thieaudio Monarch Mk II
Best in class for music
Very good for TV and video
Key differences
Music
7.1/10
9.5/10
The Thieaudio Monarch Mk II is best in class for music, while the Sennheiser HD 400S is good.
Gaming
8.6/10
6.7/10
The Sennheiser HD 400S is very good for gaming, while the Thieaudio Monarch Mk II is only fair.
Phone Calls
8.2/10
5.1/10
The Sennheiser HD 400S is very good for phone calls, while the Thieaudio Monarch Mk II is poor.
TV and Video
7.6/10
8.8/10
The Thieaudio Monarch Mk II is very good for TV and video, while the Sennheiser HD 400S is good.
Noise Reduction
5.3/10
6.0/10
The Thieaudio Monarch Mk II is only fair for noise reduction, while the Sennheiser HD 400S is poor.
Cost
$50
$999
$0
$100
$200
$300
$400
The Sennheiser HD 400S has a price of $50 and the Thieaudio Monarch Mk II costs $999.
Build Quality
8.5/10
9.0/10
The Thieaudio Monarch Mk II has excellent build quality, while the Sennheiser HD 400S has very good build quality.
"Sennheiser has done it again. The HD 400S performs well beyond its price range and is one of the better budget model headphones I’ve tried. It has very few bells and whistles and offers a simple means of listening that still delivers amazing clarity and quality. If you need a good first pair of headphones or need something that you can take out of the house, then the HD 400S is definitely for you."
"No other earphone I have listened to in the past 12 months has given me as much joy as the Thieaduio Monarch MKII. One of those IEMs will make you question where we can go from here. The sound is jaw-dropping, leaving you wanting more and more. It makes you want to run through your entire music library and reevaluate. It makes you not feel bad about paying full price for them, especially in a hobby where buyers' remorse is genuine. For me, it's top tier, rivaled by a few but not surpassed."
Get a great deal on the Sennheiser HD 400S or the Thieaudio Monarch Mk II
About Sennheiser
A family-owned company, Sennheiser is a German, high fidelity, audio equipment manufacturer founded in 1945. Their consumer audio division is now owned by the Swiss hearing aid and cochlear implant manufacturer Sonova. Sennheiser offers a wide variety of, very high quality, audio equipment solutions, from headphones to earbuds, full sets of monitoring speakers, amplifiers and microphones. They also make what is widely regarded as the best, and most expensive, headphones in existence, the HE-1 Orpheus, costing a whopping $59,000 dollars.
About Thieaudio
Thieaudio is the in-house brand of Linsoul Audio, a Chinese earbud and headphone retailer specializing in what the community lovingly calls Chi-fi, that is high fidelity brands out of China. Thieaudio was established in 2019 as the creative engineering branch of Linsoul. As of today, they market three different lines of earbuds, Voyager, Legacy and the extremely well-received Monarch.
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