MP3 Compression or Bad Mastering?

When I heard Jay-Z and Kanye’s “Murder to Excellence” on the radio and internet, the song sounded muffled.  The cymbals aren’t crisp.  The entire song, including the vocals, sounds like it’s coming out of bad speakers.  I figured maybe the spectral range of the song was too broad for mp3 compression and it was losing the high frequency detail.  I wanted to hear the real thing, so I bought the CD to get a good copy of the song.  Here’s what I got.  It’s the WAV file of Murder to Excellence from the Watch the Throne CD.

poorly mastered song

Murder to Excellence WAV file

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Avoiding Computer Viruses

The first thing to note when discussing computer viruses is that viruses are just programs, sort of like how spam is just email.  Computer users demand the ability to run any program they want, without restrictions, not have any viruses, and also not be asked any questions before running a program.  That is impossible.  I’m going to discuss four common approaches to dealing with the problem of protecting computers from unwanted programs. Continue reading

HTTPS and Web Certificates

When you go to a website and the address says https instead of http or you see a little lock button in the address bar, it means the data being transmitted back and forth is encrypted.  Any other computer along the way on the internet cannot read the contents of the transmissions.  However, sometimes you get a warning about visiting an encrypted site that says your identity is being phished or that you cannot trust the connection.  I’m going to explain what that means and when you should bypass the warning anyway and when you should not. Continue reading

Dropbox Hashing

If you add a file to your Dropbox folder that already exists on Dropbox’s servers, you don’t have to send the file.  They just mark the existing file as also being owned by you.  In fact, Dropbox works on files in 4 MB chunks, so if you modify a large file and most of it remains unchanged, they only need you to upload any 4 MB chunks that changed and don’t already exist somewhere else on Dropbox.  A lot of people are amazed or confused by this technology.  How can Dropbox’s server and your computer know that two 4 MB chunks are the same without comparing them side-by-side? Continue reading

Dropbox International Performance

I recently attended this:

Dropbox: International Performance

Come hear about several recent and future improvements to Dropbox’s international performance. Dropbox Engineer, Nipunn Koorapati, will talk about the Dropbox server architecture as well as recent optimizations to the client-server protocol for small and large files focused on our high latency international users.

We face international performance challenges at Offroad too, with systems in Switzerland and the US.  We have fairly high bandwidth between the sites, but the high round-trip times (latency) leads to problems. Continue reading

Optimal Fuel Hedging for Airlines

Some airlines are currently losing money because their fuel hedges have locked in higher prices as ticket prices fall.  I’m not sure they understand the difference between hedging and speculation.

Does anyone know how much the fuel hedging teams at airlines talk to the pricing teams?

The problem is that airlines seem to think only about hedging expenses, not revenues.  They know they have all these future scheduled flights that will consume a certain amount of fuel.  So airlines talk about pre-purchasing all that fuel.  Or they buy a particular percentage of it and call it partial hedging.  Then when fuel prices fall, new carriers can enter the market at lower prices, reducing the revenue of airlines who have already locked in their expenses. Continue reading

Round Earth Theory of Evolution

I read this article and noticed the arguments it makes are pretty weak.  It compares belief in evolution to belief in the color blue.  I’d say evolution is more like special relativity.  It’s non-intuitive and not obvious, but with enough effort it can probably be understood, analyzed, measured, observed. Continue reading

Buy Computers This Year

This year’s CES offers some exciting developments in computing.  But first, isn’t it odd that all these products are released just after Christmas?  Maybe it’s because Christmas is more about stores clearing shelves of unsold inventory at the end of the year.  Obligatory gifting customs lead people to buy discounted junk for others.  Stuff that they wouldn’t otherwise want for themselves.

I’ve held off new computer purchases for a long time, waiting for the 14nm chips from Intel.  They’re over a year late, which is understandable considering how amazing they are.  One can only imagine the internal dynamics at Intel, where the management and marketing team want to adhere to a long-term schedule of improvements while the scientists and engineers can only guess how long it will take to develop cutting-edge technology.

Here are the reasons I think 2015 is a good year to upgrade computers:

  • 14nm chips offer reduced power consumption, which means longer battery life, less heat, quieter fans or no fans.  It seems like it’s just another size in a long progression, …45, 32, 22, 14. But this time the performance change will feel like a breath of fresh air, the same way that 64-bit chips alleviated maximum RAM issues or SSD’s solved storage seek times.  And note that a 15W quad-core chip compared to a 45W dual-core chip is going to use even less than 1/3 the power to run a single thread because the power rating is for all the cores.
  • Screens are finally being marketed in terms of resolution.  I even saw a laptop screen quoted in megapixels.  I’ve always said monitors should be evaluated on megapixels and camera sensors on size.  Maybe we just had to max out practical screen sizes and camera sensor resolutions before shifting attention to the other factor.
  • vPro will make remote management of computers much easier.  With it, I can reinstall an OS at the office from across the ocean.
  • The AES-NI (Advanced Encryption Standard New Instructions) should reduce processor workload.  Even if you don’t encrypt all your data, you probably use https, VPN’s, WPA, or something else that uses AES encryption.
  • The Intel Compute Stick is fun.  Imagine the possibilities offered by a computer so small, low powered and inexpensive.  You could have a solar powered computer on your roof.  A computer in your car.  A computer attached to each TV (for people who still use TV’s!).  Sure, all that was possible before with the Raspberry Pi or by turning a smartphone into a PC, but that required effort.

Last year, a new laptop made little sense when compared to a 4 year old laptop.  With similar weight and processor performance, you would get a worse screen, better battery life, and better video performance.  It made more sense to buy a used laptop, throw in an SSD and clean the dust off its heat sinks.  I’m using a 6 year old Precision M6400 and my only complaints are weight and fan noise under heavy load.

I’m recommending the new Intel NUCs with Broadwell chips and the Dell XPS 13.  Personally, I’m going to hold off on a laptop upgrade until the 14nm chips make it into a Precision mobile workstation since I want two hard drives, more built-in ports, and a 15″ or 17″ screen (yeah, screen size also matters a bit).

recording instructions for Killbillies show

Thank you for recording the concert.  Here are some instructions.  The 3 important things are:

1. You have to press the record button twice.  The first press makes it blink red so you can set the sound levels.  The second press makes it a steady red and the recording timer begins.  I’ve been to concerts where I only pressed the button once and ended up with nothing. :(

2. Make sure the USB power is turned on so it doesn’t die when the batteries run out.

3. Set the sound level between 0 dB and -18 dB so that the peak indicators light up green once in a while, but only turn red when the audience applauds.  Try to set it with the first song and then leave it untouched.  If 0 dB leads to too much red, go with – 6 dB, then -12 dB.  -18 dB only if they’re playing really really loud.

The basic setup looks like this.main setup






IMG_1054Place it center stage, with an unobstructed view of the speakers, if possible.







This railing in the back might help elevate it above the crowd if it fits.





To turn on the recorder, press and hold the power button located on the right side, next to the USB input cord.

USB power

Also, press the button on the USB battery to turn it on.




USB icon good


Ensure that the little icon at the bottom right shows USB and not the battery level indicator.  If it’s showing the battery level indicator, it will power off when the batteries die.









input level switches


When the concert begins, press the record button, which will make the light flash red.  Then, press the record button again to make it STEADY RED.  Use the input level adjustment on the side to set the level at 0 dB, -6 dB, -12 dB or -18 dB so that the peak indicators never light up red while they’re playing, only when the audience applauds.  They should light up green occasionally while the band is playing.

Finally, I’ve included $60 of beer money and $10 in singles for tips.  Buy yourself, your friends, or the band some drinks.  If you have to leave early, hand off the instructions to Stevie or someone else along with some beer money and the return envelope.  Almost nobody showed up to the show at Hyland in 2012, but this time there should be a bigger crowd.  I’d like to see them play there next year, so I’m helping the venue and band make money.