The Soundmagic HP150 came out as a rebranded HP100, first full size closed-back from the manufacturer. MSRP price was $150. A bit on the bulky side for a closed-back, but isolation is solid and comfort above average.
Unfortunately, the hinges are made of very poor plastic and can break easily, though mine didn’t show any sign of weakness during 4 years of use. The HP151 replaced the HP150, using the same chassis and drivers.
○ Release : 2014
○ Current status : Discontinued
○ Type : Over-ear / Closed-back
○ Measured weight : 300g
○ Impedance : 32 Ohms
○ Sensitivity : ~98.5 dB/mW
○ Average used price : $50-70
Among the closed headphones I’ve heard below $300, the HP150 is one of the few I actually found decent.
Unlike a lot of headphones, sub-bass is emphasized rather than mid-bass. It gives a solid body and rumbling around 30-60hz. North of neutral in quantity, but not quite bass-head level. Upper-bass / lower-mids are largely dipped, taking away warmth from the balance.
Midrange is fine and present without particular flaw other than the low-mids big dip. Lot of voices will sound very thinny. Treble is slightly elevated, and a sharp 10 khz is apparent ; this peak was reduced a lot when I tried other pads like Brainwavz Round Pleather pads (the regular ones, not the XL that won’t fit). Extension past 10khz is decent.
Staging and imaging are honorable, not sounding too wide or narrow. This headphone delivers good detail perception, with decent transients and the well extended treble. I could see some people not liking them because of the balance : despite the neutralish tone, the lack of midrange body and warmth and the treble peak could annoy.
The cheap build and plastic hinges can be a major dealbreaker if you plan on using them a lot outside. Soundmagic released the HP151 (that looks like an updated HP150) and the HP1000 (better build but more expensive), however I would now recommend the AKG K371 as a better closed-back option.
Measurements & Resources
Bass is bumped from 30 to 80-90 Hz, with a dip from 100 to 200 Hz, causing some lack of low-mids body. Midrange remains exceptionally flat for a closed headphone, until it reaches 4 kHz. Low-treble is slightly recessed, but the energy sharply goes back around 8-10 kHz.