Audio...Headphones...

A post-Christmas impulsive shopping,
between two portable foldable on-ear headphones, I chose...

A little bit of www search after my purchase...

	JVC (JVC Kenwood)	SONY	REF: Average Ear-bud types & head phones.	REF: Better ones
Model	HS-A180	MDR-ZX310	..	..
Frequency Response upper	22000 Hz	24000 Hz	20000 Hz	45000 Hz (Denon AH-D600) 40000 Hz (Sennheiser HD700) 25000 Hz (HA-SR50x)
Frequency Response lower	10 Hz	10 Hz	20 Hz	8 Hz (HA-SR525) 5 Hz (Denon AH-D600) 3 Hz (Bowers & Wilkins P9 Signature)
Imedance at 1 kHZ	32 ohm	24 ohm		2834 ohm (BOSE QuietComfort 20) 488 ohm (BOSE QuietComfort 35) 150 ohm (Sennheiser HD700)
Sensitivity	103 dB	98 dB		111 dB (Bowers & Wilkins P9 Signature)
Driver unit size	30 mm	30 mm   Dome type		50mm (Denon AH-D600) 40 mm
colour availability	Black, White, Blue, Red	Black, White, Blue, Red
Features	Deep Bass 1.2m cord Plug: gold-plated iPhone compatible slim plug	Plug: gold-plated 4-conductor L-shape stereo mini		Remote control, Mic, noise-reduction 1.4m cord volumn control some may have protective  carrying pouch or case.  Adaptor. Detachable cable
Info on Packaging	Some specifications	No specification of Frequency Response range or Impedance, etc !! 😧
Reiews seen on www	Positive. Bought for teenagers.  (T.T)	OK. cheap. comfortable. For short commute. Sound not good.
Other Info	Magent type: Neodymium Maximum Input: 500mW (IEC)	Maximum Capacity: 1000 mW Available as standard type or Android type.		1000 mW Distortion <0.2% (1KHz/10mW) (Bowers & Wilkins P9 Signature) Distortion <0.4% (1KHz/10mW)  (Bowers & Wilkins P5 Series 2) operate with battery (BOSE Quiet Comfort 25 Acoustic Noise Cancelling)
Dimension (cm)	L21, W17, D5.5
Weight	260 g 108 g	125 g without cord		365 g (Denon AHD600) , 413 g (B&W P9)
Price RPP	USD 25.00	USD 39.99 GBP 25.00
Company HQ	Japan	Japan
Made in	PRC	PRC	mostly PRC
Materials??

I took the JVC one
though I do not norally like get black ones.

I like wider range of frequence response.
Higher impedance is good.

  
Many people said average range for human is 20-20kHz.
But "average" is meaningless.
People
with good hearing,
especially young people and some sensitve people,
the range is more than that.

Why would people be misled to buy average products
sacrificing the enjoyment / capability to hear full range of music/sounds?

Maybe I shall look for something like 8-25kHz or 6 - 30kHz.

Sometimes there are test on www.
Touch wood that I can still hear higher notes.
  
Other notes.
more wireless and or bluetooth headphones are in the market,
the specifications are slightly weaker than the one with wire/cable.



It is strange that in some countries,
manufacturers & retailers withhold specifications
on products.
To me, that is a humiliation of our intellectual capacity.

Oh, is it due to the complains or feedbacks from
those who cannot comprehend data well?
Pity. That drags down the standard of our civilization.
  
p.s.
Originally I plan to get a pair of shoes.
After trying 4, I found the heals, er,
2 too high, 2 too low/flat,
I walked into a supermarket
for retail therapy.

Given you had read
how I evaluate and choose pocket diary,
you won't expect me to just buy a headphone that quick.
    ; )

The previous headphones I have are mostly just the earbud type
which came with either my walkman, discman, mobile phones, etc.

Except one shocking pink one. 😊

Consumers are often not given all the facts
to help make informed decisions.
Some locations of shops do no have data signal to go on line.
Many reviews in the media are not fully neutral.
Consumer magazines reviews are not professional enough, either.