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Always interested in offers/projects/new ideas. Eclectic experience in fields like: numerical computing; Python web; Java enterprise; functional languages; GPGPU; SQL databases; etc. Based in Santiago, Chile; telecommute worldwide. CV; email.

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© 2006-2017 Andrew Cooke (site) / post authors (content).

Sennheiser HD25

From: "andrew cooke" <andrew@...>

Date: Sat, 18 Nov 2006 17:13:42 -0300 (CLST)

[My email is working again, so this blog is back from the dead - my server
has a new power supply and a new CPU cooler]

Pauli brought me a pair of Sennheiser HD25s back from the states (thanks
Eric for being my Amazon drop-off point).  She said they look ugly, but I
quite like them - at least when I'm not wearing them.  They are smaller
than I expected and when around the neck don't look too intrusive.  When
they're on your head, however, they look more "obvious" than my Grados. 
The trouble is that the headphones are quite deep and the headband goes
round the "outside", so they look very wide.  Also, you can see the
various wires, which makes them look rather "technical".  In other words,
you look like a geek walking down the street.  Which is annoying, because
I bought them for doing just that - they're closed back and fairly
well-isolated (not as good as the in-ear Shure phones that I tried, but
pretty good - see below).

Anyway, as I was saying, they are quite compact when they're not being
worn, and they're lighter than i expected.  They're kind of "pro" looking,
but in a miniaturised, slightly "cute" way.  I keep thinking they're Sony
phones, if that helps understand what I mean.

They're moderately comfortable - as about comfortable as "on ear" can be. 
After a while they press my ears against my glasses, and the plastic
padding gets a bit sweaty (I think velour replacement pads are available).

So.  How do they sound?  Overall, they're OK.  With the isolation and
moderately compact size, I can't see a better solution for traveling
(in-ear phones do not work for me - my left ear seems to be a funny
shape).  There are several negatives though: a slightly harsh, metallic
sound, as if there's too much of some high (but not very high) frequency;
poor stereo; surprisingly little bass; a slight "shut in" sound that I
guess may be unavoidable for closed phones.  They sounds neither warm, nor

On the positive side, I am (this is a cliche I've read in so many audio
reviews over the years, yet in this case it really seems to be true - I
keep noticing new examples) hearing things I have not heard before.  I
don't know if it's the quieter background or the treble emphasis, but I'm
noticing a lot more of the comments from musicians/engineers as tracks
fade in/out (and that's another cliche people should drop).  It's also
easier (despite the rather restricted stereo) to listen to individual
instruments.  They sound very "precise".

Hmmm.  Overall, this review is rather negative.  I do like these - and
I've already worn them outside once (only one person stared).  But they're
a definite compromise for traveling.



From: "andrew cooke" <andrew@...>

Date: Sat, 18 Nov 2006 17:24:36 -0300 (CLST)

I forgot to describe the isolation.  For some reason the fit on my left
ear is better than the right (I think the right will improve over time as
the earcup squashes) which makes the sound slightly "asymmetric" and
means, I suspect, that I have some extra noise coming through on that

Anyway, they really kill high frequency noise.  I am writing this in my
"office" next to my noisy old server (which contains 5 fans, if you
include the PSU) which whirrs away, with traffic going past outside, and
Maiden Voyage playing quite loudly on the speakers.  With these phones on
I can still hear the trumpet, sax, piano and bass, but as much simpler
"pure" tones.  The computer whirr, the splash of the cymbals (almost - I
just caught something then) and the cars outside are all gone.  So it
seems to block high frequencies and general "noise" (which is mainly high
frequency so that's the same thing), but not so much lower (ie "mid")
frequencies like musical tones.

Walking down the street, I still hear cars go past, but not their
approach, and was surprised by several bicycles passing me.  One thing I
did hear, which was new and surprising, was the thump of each foot
landing, which seemed to be passing up through my leg bones, inside my


Headphone Blog

From: "andrew cooke" <andrew@...>

Date: Sat, 18 Nov 2006 21:29:40 -0300 (CLST)

Mentioned at
(disclaimer: I suggested the link).

Old Style

From: "andrew cooke" <andrew@...>

Date: Sat, 25 Nov 2006 12:47:26 -0300 (CLST)

Realised last night what I like about the style of these headphones.  The
split headband reminds me of old radio operator phones:


Comparison with Bose Headphones

From: "andrew cooke" <andrew@...>

Date: Sun, 25 Feb 2007 18:31:19 -0300 (CLST)

A couple of weeks ago I got the chance to compare my Sennheiser HD25s with
a pair of Bose noise-cancelling phones - I don't know the model (they were
my boss's), but they must be a year or two old.

First I was surprised to find that the noise isolation of the Bose was
similar to the HD25s *without noise cancellation*.  Turning the noise
cancellation on therefore made the Bose much quieter than the Sennheisers.

With the Boses turned on my MP3 player could be heard - the sound quality
was not as good as the Sennhesiers.  They were missing both treble and
bass (I was surprised at how bad they sounded, since I had just been
impressed by the sound cancelling abilities).

I wondered if the poor sound was associated with the noise cancelling, but
I couldn't compare sound quality with the Boses switched off, as then I
could not hear any music at all.  I don't know if this is normal, or if my
MP3, which is all I had as a source, couldn't generate enough power to
drive them in that mode.

The build quality of the Bose were OK, and they came with a little
zippered bag/box, but they didn't feel "bombproof" like the Sennheisers. 
They also looked a bit "shiny".

So active noise cancelling is much better than I had assumed, but the Bose
models I listened to were rather less good at actually playing music.


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