- <title>Facebooks ability to sell your personal information is the real Cambridge Analytica scandal</title>
- <link>http://people.skolelinux.org/pere/blog/Facebooks_ability_to_sell_your_personal_information_is_the_real_Cambridge_Analytica_scandal.html</link>
- <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Facebooks_ability_to_sell_your_personal_information_is_the_real_Cambridge_Analytica_scandal.html</guid>
- <pubDate>Wed, 21 Mar 2018 16:30:00 +0100</pubDate>
- <description><p>So, Cambridge Analytica is getting some well deserved criticism for
-(mis)using information it got from Facebook about 50 million people,
-mostly in the USA. What I find a bit surprising, is how little
-criticism Facebook is getting for handing the information over to
-Cambridge Analytica and others in the first place. And what about the
-people handing their private and personal information to Facebook?
-And last, but not least, what about the government offices who are
-handing information about the visitors of their web pages to Facebook?
-No-one who looked at the terms of use of Facebook should be surprised
-that information about peoples interests, political views, personal
-lifes and whereabouts would be sold by Facebook.</p>
-
-<p>What I find to be the real scandal is the fact that Facebook is
-selling your personal information, not that one of the buyers used it
-in a way Facebook did not approve when exposed. It is well known that
-Facebook is selling out their users privacy, but a scandal
-nevertheless. Of course the information provided to them by Facebook
-would be misused by one of the parties given access to personal
-information about the millions of Facebook users. Collected
-information will be misused sooner or later. The only way to avoid
-such misuse, is to not collect the information in the first place. If
-you do not want Facebook to hand out information about yourself for
-the use and misuse of its customers, do not give Facebook the
-information.</p>
-
-<p>Personally, I would recommend to completely remove your Facebook
-account, and take back some control of your personal information.
-<a href="https://www.theguardian.com/technology/2018/mar/19/how-to-protect-your-facebook-privacy-or-delete-yourself-completely">According
-to The Guardian</a>, it is a bit hard to find out how to request
-account removal (and not just 'disabling'). You need to
-<a href="https://www.facebook.com/help/224562897555674?helpref=faq_content">visit
-a specific Facebook page</a> and click on 'let us know' on that page
-to get to <a href="https://www.facebook.com/help/delete_account">the
-real account deletion screen</a>. Perhaps something to consider? I
-would not trust the information to really be deleted (who knows,
-perhaps NSA, GCHQ and FRA already got a copy), but it might reduce the
-exposure a bit.</p>
-
-<p>If you want to learn more about the capabilities of Cambridge
-Analytica, I recommend to see the video recording of the one hour talk
-Paul-Olivier Dehaye gave to <a href="">NUUG</a> last april about
-<a href="https://www.nuug.no/aktiviteter/20170404-big-data-psychometric/">
-Data collection, psychometric profiling and their impact on
-politics</a>.</p>
-
-<p>And if you want to communicate with your friends and loved ones,
-use some end-to-end encrypted method like
-<a href="https://www.signal.org/">Signal</a> or
-<a href="https://ring.cx/">Ring</a>, and stop sharing your private
-messages with strangers like Facebook and Google.</p>
+ <title>Measuring the speaker frequency response using the AUDMES free software GUI - nice free software</title>
+ <link>http://people.skolelinux.org/pere/blog/Measuring_the_speaker_frequency_response_using_the_AUDMES_free_software_GUI___nice_free_software.html</link>
+ <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Measuring_the_speaker_frequency_response_using_the_AUDMES_free_software_GUI___nice_free_software.html</guid>
+ <pubDate>Mon, 22 Oct 2018 08:40:00 +0200</pubDate>
+ <description><p><img src="http://people.skolelinux.org/pere/blog/images/2018-10-22-audmes-measure-speakers.png" align="right" width="40%"/></p>
+
+<p>My current home stereo is a patchwork of various pieces I got on
+flee markeds over the years. It is amazing what kind of equipment
+show up there. I've been wondering for a while if it was possible to
+measure how well this equipment is working together, and decided to
+see how far I could get using free software. After trawling the web I
+came across an article from DIY Audio and Video on
+<a href="https://www.diyaudioandvideo.com/Tutorial/SpeakerResponseTesting/">Speaker
+Testing and Analysis</a> describing how to test speakers, and it listing
+several software options, among them
+<a href="https://sourceforge.net/projects/audmes/">AUDio MEasurement
+System (AUDMES)</a>. It is the only free software system I could find
+focusing on measuring speakers and audio frequency response. In the
+process I also found an interesting article from NOVO on
+<a href="http://novo.press/understanding-speaker-specifications-and-frequency-response/">Understanding
+Speaker Specifications and Frequency Response</a> and an article from
+ecoustics on
+<a href="https://www.ecoustics.com/articles/understanding-speaker-frequency-response/">Understanding
+Speaker Frequency Response</a>, with a lot of information on what to
+look for and how to interpret the graphs. Armed with this knowledge,
+I set out to measure the state of my speakers.</p>
+
+<p>The first hurdle was that AUDMES hadn't seen a commit for 10 years
+and did not build with current compilers and libraries. I got in
+touch with its author, who no longer was spending time on the program
+but gave me write access to the subversion repository on Sourceforge.
+The end result is that now the code build on Linux and is capable of
+saving and loading the collected frequency response data in CSV
+format. The application is quite nice and flexible, and I was able to
+select the input and output audio interfaces independently. This made
+it possible to use a USB mixer as the input source, while sending
+output via my laptop headphone connection. I lacked the hardware and
+cabling to figure out a different way to get independent cabling to
+speakers and microphone.</p>
+
+<p>Using this setup I could see how a large range of high frequencies
+apparently were not making it out of my speakers. The picture show
+the frequency response measurement of one of the speakers. Note the
+frequency lines seem to be slightly misaligned, compared to the CSV
+output from the program. I can not hear several of these are high
+frequencies, according to measurement from
+<a href="http://freehearingtestsoftware.com">Free Hearing Test
+Software</a>, an freeware system to measure your hearing (still
+looking for a free software alternative), so I do not know if they are
+coming out out the speakers. I thus do not quite know how to figure
+out if the missing frequencies is a problem with the microphone, the
+amplifier or the speakers, but I managed to rule out the audio card in my
+PC by measuring my Bose noise canceling headset using its own
+microphone. This setup was able to see the high frequency tones, so
+the problem with my stereo had to be in the amplifier or speakers.</p>
+
+<p>Anyway, to try to role out one factor I ended up picking up a new
+set of speakers at a flee marked, and these work a lot better than the
+old speakers, so I guess the microphone and amplifier is OK. If you
+need to measure your own speakers, check out AUDMES. If more people
+get involved, perhaps the project could become good enough to
+<a href="https://bugs.debian.org/910876">include in Debian</a>? And if
+you know of some other free software to measure speakers and amplifier
+performance, please let me know. I am aware of the freeware option
+<a href="https://www.roomeqwizard.com/">REW</a>, but I want something
+that can be developed also when the vendor looses interest.</p>
+
+<p>As usual, if you use Bitcoin and want to show your support of my
+activities, please send Bitcoin donations to my address
+<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>