Tuesday, October 31, 2006
This single features a star-studded ensemble (Beck, Sum 41, The Arcade Fire) known as the NORTH AMERICAN HALLOWEEN PREVENTION INITIATIVE. Both a trick and a treat, this song is a satire - as well as a charity-benefit song with all proceeds being donated to UNICEF.
Monday, October 30, 2006
Today, YouTube removed all of its Comedy Central content. Google knew this was coming but you have to wonder if YouTube will be worth that $1.65 billion on Monday. The take down request comes a year after a Wired interview where Daily Show Executive Ben Karlin encouraged viewers to download: "If people want to take the show in various forms, I'd say go."
Now the video clip in one of my earlier posts about damn spammers doesn't play. Oh well. It was pretty humorous. Sorry if you missed it.
Thursday, October 26, 2006
In this article, he covers the basic math computations using the logarithmic scale and decibels. He briefly mentions that human hearing is not linear -- we can hear slight changes at low levels, but don't notice similar differences at high volumes. I think he plans to discuss this topic in more detail in a later installment.
In case he doesn't mention this... I thought I would go ahead and offer a little more detail. As mentioned in earlier installments, sound is created when something strikes another object. So when a guitar string vibrates, it is striking against air molecules. The vibrations cause the air nearby to compress and expand. A shorter string vibrates at a faster rate than a longer string, creating a higher pitched sound... The more compressed (or expanded), the more energy it contains and can expend. The loudness, or intensity of the sound is measured in terms of the amount of energy passing each second through one square centimeter of area. Energy expended over time is power and the unit is the watt. A watt is one joule per second. As you know, a 75 watt light bulb is pretty bright. A 40 watt bulb, not so bright. One of those small little night lights used to find the bathroom without bumping into a wall is probably around 1/4 watt. The amount of power found in sound is really small. The amount of power carried by ordinary conversational sound is about 1/1000 watt.
The human ear detects the difference in loudness by ratios of the power, not the actual differences. So, a 2000 microwatt (1/2000 watt) sound will seem louder than a 1000 microwatt sound, but a 3000 microwatt sound will not seem to sound louder by as much again. It actually takes a 4000 microwatt sound to seem louder by as much as a 2000 microwatt sound compares to a 1000 microwatt sound. To get a sound that is as much louder again than a 4000 microwatt sound, we would need an 8000 microwatt sound. The rations 2000/1000, 4000/2000, and 8000/4000 are all equal even though the difference are not, and it is the ratios that the ear detects.
This is where he explains that we don't hear linearly, but on a logarithmic scale. When one sound carries 10 times the power of a second sound, the ratio of the first to the second is 10 and the log (base 10) of this is 1. The difference in sound power is then said to be one 'Bel'. If a sound is 100 times more powerful than another sound, it is two Bels louder, 1000 times would be 3 Bels, etc. Since the Bel is too large of a scale for practical use, we use the decibel, which is 1/10th a Bel. A sound is a decibel louder than another when the first is 1.26 times as powerful as the second -- log(1.26) is about equal to 0.10.
The decibel is used one of two ways:
- to measure power or intensity
- to measure amplitude
When dealing with these ratios, they use a standard reference for the denominator. For sound power or intensity, the denominator is the threshold of hearing (about the sound of a mosquito flying about 3 meters away), which is about 10-12 watts/m2. Sound pressure level (SPL) is usually used to specify the sound intensity. The upper limit of sound, before it behaves like a shock wave is about 194 dB (SPL). For comparison, windows break at about 163 dB; the sound of a jet engine from 30 meters (100 feet) is about 150 dB; the threshold of pain is about 130 dB; the sound of a train horn from 1 meter is about 120 dB and at this level can cause immediate perforation of your ear drum (so don't stand too close to a train when the horn goes off); and, loud music in a dance club is probably at 100 dB. They say anything above 85 dB is considered harmful and over 95 dB for long periods is considered unsafe.
BTW, so far, no one has entered the contest. I wonder why...? Is it the award -- no one likes beer or cheese? If so, any recommendations for a more enticing award? Is it because no one likes taking tests? Oh come on, it should be easy. All you have to do is read the articles. Is it because no one is reading those articles? (I know, I know, not many people are even reading this blog, so I'd really like to come up with useful info that potential readers find interesting). I'd really like some feedback on this. If there is a response, I might go ahead and post another test covering the later installments and award the winner with something like a gift certificate from Amazon.
Tuesday, October 24, 2006
Here's the test:
- True or False, sound requires a medium through which to propagate; sound does not travel through a vacuum.
- True or false, the speed of sound is faster at lower temperatures.
- Airborne sound travels in the form of:
- Latitudinal waves
- Awesome waves
- Transverse waves
- Longitudinal waves
- Attitudinal waves
- In the early evening when the air closer to the ground is still warm and the air higher in the sky is cool, sound waves will:
- Continue moving straight
- Reflect off the cooler air
- True or False, sound waves consist of alternating regions of compression (increased pressure) and rarefaction (decreased pressure). There is also an ambient pressure before the wave propagates.
- True or False, a pure tone is a sound with sinusoidal time fluctuations.
- The above figure represents a pure tone waveform. True or False, a period (T) is the time it takes for the wave to go from the highest amplitude to the lowest amplitude.
- True or false, in general, all sounds move at the same speed within the same medium.
- Given a pure tone with a period of 1 ms, what is the frequency of the tone?
- If a tree falls in the forest, does it make a sound?
- True or false, phase can be used to compare the alignment of two tones of the same frequency. This difference between two tones is known as a phase offset or phase difference. Phase offset is also loosely referred to as simply phase.
- Two pure tones with a frequency of 1000 hertz are 90 degrees out of phase. What is their phase offset in units of time?
- What is a convenient way to diagram how sound moves?
- Bubble diagrams
- Wave fronts
- Sound rays
- Both a and c
- Both b and c
- Since c (speed of sound) = f (frequency) multiplied times λ (wavelength); what is the wavelength of a pure tone with a frequency of 1500 hertz at STP (standard temperature and pressure)?
- True or false, the angles a sound wave hits and reflects off a smooth surface are the same.
- When two waves have a non-zero phase offset, they are said to be in phase. When two waves have zero phase offset, they are out of phase.
- True or false, when a sound wave refracts through another material with a higher speed of sound, the wavelength of the sound wave will decrease.
- True or false, the frequency (f) is the rate at which the wave repeats (cycles per second, called hertz).
To qualify for entry into this "contest", you must leave a comment to this post with some way to identify yourself -- maybe leave a nickname and your location. DO NOT INCLUDE YOUR ANSWERS IN YOUR COMMENT. Then submit your answers to firstname.lastname@example.org. Be sure to include the same nickname identified in the exam's comments. The winner will be announced next Tuesday (Halloween), so you can submit answers until Monday night, which is October 30th.
I think I'm going to postpone the test because I'd like to post it after all installments are posted at DesignLine. BTW, the highest score will get their choice of either a six-pack of wonderful Wisconsin micro-brewed beer or a block of premium cheese.
Monday, October 23, 2006
Friday, October 20, 2006
"Open architecture is a type of computer architecture that allows users to upgrade their hardware in all of the computer hardware & components (for example the IBM PC had an open architecture). This is the opposite of a closed architecture, where the hardware manufacturer chooses the components, and they are not generally upgradable (for example the Amiga 500 home computer had a closed architecture).
Open architecture allows potential users to see inside all or parts of the architecture without any proprietary constraints. Typically, an open architecture publishes all or parts of its architecture that the developer or integrator wants to share. The open business processes involved with an open architecture may require some license agreements between entities sharing the architecture information."I'm not sure if we will ever be able to do this, but it is something I am interested in achieving. I think there is great potential here. It may even turn part of the consumer electronics industry upside down or inside out. Of course, this may not appeal to the ultra expensive, high end, "audiophile" producers and consumers, but I think it would really be great for the rest of us.
What do you think? As a consumer, would you like to purchase a system that could be expanded from 2 channels to 8 channels? Or upgrade the DACs or amplifier modules when a new generation is released? Be able to choose from a variety of case manufacturers to have one that best fits your style?
If there are any reps from manufacturers of amplifier modules, power supplies (the best technology for this would be switching power supplies or SMPS), or sound cards reading this, I'd love to hear what you think about this idea? Do you think it would expand your market, or not? Do you think the technical hurdles for designing your components to meet a specific form factor and use of standard connectors would be too limiting? Maybe someone like Creative would offer a version of their X-Fi that would be compatible -- and like the "Intel Inside" promo, they could have "X-Fi" inside. Of course, we could also have "UCD powered", etc.
Wednesday, October 18, 2006
Tuesday, October 17, 2006
Monday, October 16, 2006
Friday, October 13, 2006
BTW, the UW-Madison and Wisconsin Historical Society historical document and book collection, at 7.2 million holdings, is one of the largest collections in the United States, ranked 11th in North America. I doubt this is included in this project, but an interesting side note about UW-Madison/WHS, is they co-sponsor the Wisconsin Center for Film and Theater Research. The WCFTR is one of the largest archives of entertainment industry research material in the world.
The University of Wisconsin-Madison joins the impressive list of project partners that includes the University of California, University of Michigan, Harvard University, Stanford University, the New York Public Library, Oxford University and the Universidad Complutense de Madrid.
Thursday, October 12, 2006
After inserting the image, I wasn't very happy with the way it looked next to the rest of the blog's colors. So for the past few days I've experimented with different color options. I think I've finally made up my mind. Still not entirely happy, but we'll leave it like this for a while until we get bored with it or unless some people tell us these colors are making them ill.
Tuesday, October 10, 2006
Sunday, October 08, 2006
I've heard that the artist only makes about 10% of the CD sale price, but wasn't sure how the rest of it broke down. This also shows the distribution based on a $15.99 retail price. I wonder what it would look like for discounted CDs. I would assume the retailers take the hit there. It's also not clear to me how many companies, organizations or whatever are taking a piece of the pie. Do the labels get the label overhead, marketing/promotion, label profit, distribution and packaging/manufacturing? If so, they end up with 55%. The retailers are getting 31%. Granted, a much smaller percentage is actual profit. Anyhow, I could see how an artist might benefit from alternative promotion and distribution methods like doing it themselves or working with one of the new breed of record labels like Nettwerk Music Group, Nonesuch Records or Magnatunes. I also like the name for the organization that is the source for this pie chart - the Almighty Institute of Music Retail.
Friday, October 06, 2006
During the last week or so, I've been getting lots of "undeliverable mail" messages, saying the message from 'someweirdname at amplioaudio dot com' could not be delivered, etc. Each message has some different email name like 'nzogo at amplioaudio dot com'. None of them are accounts I set up with Yahoo!'s mail service. A lot of the undeliverable messages show that the messages were trapped by some spam filter. Obviously, some spammer is sending out thousands of messages using the amplioaudio domain. Now lots of people will probably block amplioaudio and legit messages will all get dumped in their spam folders. This pisses me off!! Does anyone know if there is any way to stop this? I contacted Yahoo!'s tech support several times, but they haven't responded. Any ideas???
The article also mentions that in some areas the download speeds are already there. Like those lucky bastards who currently have Verizon's 30 Mbps Fios service or even 100 Mbps from a Swedish cable modem service. I wish we had something like that here in Madison. I think my AT&T 6 Mbps DSL service is the best we can do here.
Thursday, October 05, 2006
If anyone reading this blog is at the show or planning to attend in the next few days, feel free to contact us and share any interesting information. I'd really like to hear about these workshops:
SURROUND SOUND–NOW & IN FUTURE
HIGH RESOLUTION AUDIO — DISCS VS. DOWNLOADS
CONTENT PROTECTION AND AUDIO DISTRIBUTION: CAN THIS MARRIAGE BE SAVED?
WHY THE ROOM IMPULSE RESPONSE AFFECTS EVERYTHING WE HEAR: What Is It; Why Does It Matter, and How Do We Measure It?
HUMAN FACTORS IN THE DESIGN OF AUDIO PRODUCTS AND SYSTEMS
THE HOWS AND WHYS OF DELTA SIGMA PROCESSING
And, of course I would like to spend some time in the exhibit hall. If you are an exhibitor, please free to enter any comments below.
Since I can't attend this year's convention, I'll do the next best thing and try to read a bunch of blog entries covering the show. I've searched for 'AES blog' and only come up with these so far:
Professional A/V Industry Blog
Peter at WordPress
John Atwood (ClariSonus)
Anablog (note: I discovered this blog on 10/31/06)
If I come across any others I will add them to this list. 10/6/06 update - okay, Brian Dipert (click on Brian's Brain blog, which I just added to the list) is at the AES convention. Hopefully, he will post something about the convention in the next few days. Another update: just found a few more, I'll just add them to the list.
Wednesday, October 04, 2006
Anyhow, here's an IDC report that talks about the growing popularity of HTPCs or what they call Media Center PCs. Click on this link to read the full article.