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Welcome to my blog, which was once a mailing list of the same name and is still generated by mail. Please reply via the "comment" links.

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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Colorless Green.

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SVG experiment.

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Data access via web services.

Cache rewrite.

Extending OpenSSH.

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Logitech Squeezebox Boom on OpenSuse

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

Date: Mon, 22 Dec 2008 20:42:42 -0300 (CLST)

I just came back from the States, where I bought myself a new toy -

So far I am *very* happy with this - I played music from the internet
(mainly KEXP and BBC Radio 6) in my hotel room, and am now listening to
the music stored on my server (everything, shuffled - currently playing
Devendra Banhart).

The build quality is very good (the shiny black shows fingerprints like
crazy, but the main interface panel is a matt black which is much better).
 There's a cute little remote control that sits magnetically on the
(sloping) top of the unit when not in use.  It feels very "solid" and the
power supply is variable voltage (so works fine in the USA and Chile,
although you need a pin adapter).  It's slightly smaller than I expected
from the photos.

The sound quality is pretty good.  Better than I expected, to be honest. 
It has quite good extension without being "boomy".  The treble is a little
harsh, I think, but my ears are old, so what do I know?

Curiously I just tried it with headphones and it doesn't sound that good
at all (Sennheiser HD 555s), but the system I making comparison with is
perhaps unfair - at my computer I listen to a fairly expensive (semi-pro
M-Audio) card through an old Mission Cyrus amp (so old I've had to bridge
the volume and input selectors... :o)  There's no bass (you can hardly
hear the bass drum in the Pogues track currently playing); the voice is
too far forwards/harsh; generally the sound is "flat".  Note - I also
tried swapping the power supply to a transformer (rather than the switch
mode box supplied), wondering if noise was responsible for the harshness,
but it made no difference.

Anyway, despite that negative detour, it does sounds good for a small box

The standalone setup/interface is a dream.  You plug it in and the display
guides you through obtaining an interface (entering text by hand is a
royal pain, selecting letter by letter with the knob, but thankfully not
necessary in normal use - when using WiFi a list of SSIDs is displayed,
for example).

You do need to have a computer to register the player on "SqueezeNetwork".
 But once you do that a slew of radios are provided via menus (the central
knob scans through menu lists; pressing the knob selects an option; there
are also separate forward/back buttons).

So my only worry there is that this requires Logitech's SqueezeNetwork
service to exist.

You can also control the player via Logitech's web site (I am not being
very clear here, but "SqueezeNetwork" is both the name of the central list
of stations and a web site that lets you control the player, modify menus,
etc).  For example, there is support, via the SqueezeNetwork website, for
last.fm and pandora (but they are both blocked in Chile which is why I
have started pirating music, incidentally - for freaking *years* I was the
only person I knew who bought all the music they ripped... but killing
Pandora was the last straw)

Anyway.  You can also install software on your own computer to expose the
music you have stored there.  For opensuse I did the following:

- Download the rpm from the SquezeNetwork site -

- Add the directory containing that RPM as a local repository (in Yast go
to the repository manager and add a local directory as a simple RPM

- That lets you then select "squeezecenter" in Yast as a piece of software
to install (which should also load dependencies like MySQL, Perl etc)

- Once installed, you need to enable and start the service.  As root:
  # chckconfig -a squeezecenter
  # /etc/init.d/squeezecenter start

- The interface is a website on http://localhost:9000 - go there and
select the directory where your music is stored.  Note that the software
does take some time to index the files, if you have a few - if the
interface seems very unresponsive, wait a while.

- Finally, open up firewall ports listed here -

- With that done you can connect to "SqueezeCenter" (as opposed to
"SqueezeNetwork") when starting the radio (to reset, by the way, hold down
the power button for a few seconds).  Note that I did have to enter the
address of my server on the local network.

As I write all this I start to see how complex the whole system is. 
Despite that, it has been very easy to use.  Obviously I have a lot of
experience with computers; perhaps my parents would be more confused (but
then they would also be using the Mac install, which is probably

The SqueezeCenter web interface is only so-so.  Compared to SqueezeNetwork
it's much less polished.  But this is a huge advance on my previous
attempts to use Apple's Airport Express with Linux.

In summary - if this continues to be as good as it has been so far I will
be buying a SqueezeBox for the hifi...


SqueezeCenter gets better!

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

Date: Mon, 22 Dec 2008 20:53:33 -0300 (CLST)

I just re-opened the local SqueezeCenter website and it's showing much
more info, and being more responsive, now.  Looks like it was still busy
building up the database of tracks when I posted earlier.

This is great :o)



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

Date: Tue, 23 Dec 2008 08:19:51 -0300 (CLST)

After playing around some more, I am starting to see the radio more as an
interface to remote software than a computer in its own right.  This seems
to better explain how it behaves.

So selecting "SqueezeCenter" makes it an interface to the software running
on my own computer; selecting "SqueezeNetwork" makes it an interface to
the software running on Logitech's computer.

Both programs (the one running on my computer, called SqueezeCenter, and
the one running on Logitech's, called SqueezeNetwork) have their own
settings.  So the list of favourites, or the screen brightness, or the
date format, for examples, can depend on which is chosen.

Things are slightly more complicated as the player itself appears to have
some memory, and the SqueezeCenter software by default attempts to
synchronise with SqueezeNetwork.

This may seem like irrelevant details. but it helps understand why, for
example, when you are connected to SqueezeCenter, you get a menu option
for SqueezeNetwork (and vice versa), and why switching causes the radio to
"blank out" for a second.  It also helps explain why some settings don't
always seem to apply.


Separate DAC for Headphones

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

Date: Tue, 23 Dec 2008 08:38:21 -0300 (CLST)

There's a white paper on the audio design -
- which explains that there's a separate DAC for the headphones.  I guess
that explains how it's possible for the unit itself to sound so much
better through its own speakers than it does through headphones.

Listening normally (ie with the speakers) at low volume levels really is
very good - last night, for the first time ever, I actually enjoyed
Bitches Brew!


Command line player for listening to SqueezeCentre on Linux

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

Date: Wed, 31 Dec 2008 18:01:01 -0300 (CLST)

When I am working at my computer the Boom is in the other room.  But it's
possible for the computer itself to connect to the SqueezeCentre software.
 The URL is http://localhost:9000/stream.mp3

You can use any software to listen, but if you like doing stuff from the
command line, the following works (just hit return again in the same
window to stop it):

  mplayer http://localhost:9000/stream.mp3 > /dev/null 2>&1

(Volume has to be controlled by a volume/mixer tool, but only needs
setting once).


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