Thanks to USA Today and the Bucks Courier Times for these excellent charts…Best-Clean-Practices
Note that you can download and print these charts. Look for the download arrow in the bottom margin of the picture.
It’s often hard to find suitable places to tie a temporary indoor banner. An “X” pole will keep it taught and allow it to be leaned against a wall or chairs. Poles made of 3/4″ PVC pipe are easily fabricated and may be joined by short scraps of 1″ PVC pipe as shown elsewhere on this site (see below).
Here’s a sketch:X-Support-for-Banner
Hooks made from coat hanger wire insert into the open ends of the pole and secure the top corners of the banner. The weight of the banner tends to splay the “X”, drawing the top edge of the banner tight. Further tensioning can be accomplished by securing the lower corners of the banner with bungee cords. This whole assembly may be leaned against a wall or lashed to chairs with additional bungee cords.
Here’s the article on pole fabrication:
Ever since I moved to the retirement community where I have lived since 2013 I’ve been struggling with the bad acoustics of our meeting hall. There is so much reverberaton that the sound from our PA system gets muffled and is prone to annoying feedback.
We are seniors, many with hearing loss. The staff does not include a crew of AV engineers to keep things tweaked up, and few residents are versed in how to use a microphone properly. So it’s not surprising that many meetings and performances were marred by bad sound.
Today audio engineers have hi-tech solutions to these problems: a digital toolbox of enhancements for the sound that compensates for the problems just mentioned. They have technical names like “equalizer”, “compressor”, “notch filter”, and “limiter.” They allow a public address (PA) to become a sound system tailored to the acoustics of the room. The categorical name for this technology is “Digital Signal Processors” or DSP.
A professional sound system for a medium-size theater can cost in the mid-five figures. We hired an acoustics expert to make a recommendation. He brought instruments and went about the hall firing a starter’s pistol and making other loud noises and in due course told us that acoustic wall treatments and such would not be much help, but that we should consider an advanced audio system featuring DSP for each of the speakers in the room. This would allow each speaker to be custom adjusted for each of the several different arrangements of chairs and performance areas.
These engineering adjustments would be saved in the audio console as presets so that house staff could simply select the preset that corresponds to the room layout for any given event. If successful, the result would be loud clear sound that was below the threshold of feedback.
We already had a DSP device capable of presets. It had been purchased and installed around the year 2000 and was a cutting-edge device with a price to match – about $1,200. The Sabine Graphi-Q converts the sound from an audio mixer to a digital stream, splits it into 31 one-octave “bands”, each of which has its own volume control. In addition is has 12 filters that can trap and tune out a squeal from feedback. But the processing doesn’t stop there, next it detects peaks of loudness in the stream and tamps them down (compression) essentially normalizing the loudest blasts. This has the effect of making the average audio less loud, the stream is amplified (gain) back to the original average level. And just in case the compression isn’t enough to prevent a super loud blast, there is another filter that imposes a loudness ceiling (limit).
All of this processing of the stream happens in less than two-thousandths of a second so it’s imperceptible to the listener. But if a room has more than one speaker, the transit time for sound is perceptible. Sound travels about 1,100 feed a second. If you are 50 feet from the source, the sound reaches you with a delay of about 50 thousandths of a second. When the sound from a second speaker close to the listener combines with the delayed sound, the interference between the sounds can make it fuzzy. That aggravates hearing loss issues. To fix this, the Graphi-Q has an adjustable delay setting that is set for the distance that the loudspeaker it controls is from the stage.
The delay is the last link in the chain of processes accomplished by the Graphi-Q processor. Installing and adjusting these devices is a lab course in digital signal processing techniques. It allows a novice technician to experience hands-on what he has learned about in textbooks.
The Graphi-Q is obsolete. On eBay you will find them offered for between $60 and $200, though Guitar City has one listed at the original $1,200 price. Sabine, the manufacturer, has closed its doors. But the company website has been preserved and archived (link below). That site is a gem of useful information because it includes whitepapers on signal processing techniques, acoustics, and the manuals and software for the Graphi-Q. This means that for about $100 you can buy a full featured laboratory to learn about DSP. It’s the lab course for Audio Engineering 101.
Hearing aids are a business and a technology product. But the sale of hearing aids has been cloaked in an aura of mystery and pseudo-medical veneer. Although audiology is a profession, and practitioners are licensed and awarded the title of “Doctor”, if there is something wrong with your ears, you see a physician, not an audiologist. For example, audiologists are obliged to refer you to a medical doctor if your ear canal is blocked by wax, or if there are other indications of pathology that affect your ability to hear.
The hearing aid is a prosthetic device that compensates for hearing loss. It can be much more than a simple amplifier of sound. The latest ones process the sound much as a sound engineer “mixes” the sound of a vocalist or an orchestra.
Our hearing is a sense. To hear well is to correctly perceive the sounds we are interested in within a torrent of irrelevant sounds. Our ears must convert sound waves into nerve impulses, and our brain must then interpret the stream of impulses. Lots can go wrong along the way.
Interfering noises, and poor quality of sound at the source can be compensated for with external devices. Most of the benefits of hearing aids come from processing the sound to optimize it for the ear.
But neurological conditions, cognitive issues, and individual perceptual talents all contribute to the ability or inability to hear well. Most of these are not helped by devices. Training those we communicate with to speak more slowly, enunciate carefully, face us when speaking, and give us get the context for a remark are all beneficial in compensating for the internal processing of spoken communication.
As a sound engineer and technician, I’m often asked about hearing aids and other devices that help people hear better. The first step is to gain an understanding of your individual hearing problem. See a doctor first, then shop audiologists. The quality of testing, and the value vs. price of the products varies widely. An advanced technology hearing aid from Costco can be half the price of a less capable device sold by an independent audiologist. Audiologists sell certain brands and not others, so you can expect them to promote what the have. This may or may not be in your best interest.
Past abuses in the hearing aid field have prompted many states to mandate a 90-day full money back satisfaction guarantee. A thorough hearing exam will test the sensitivity of your ears to sounds of different loudness levels at different pitches. This is critical to adjusting a hearing aid to compensate so that you hear more like someone with no hearing loss. They may also test your ability to discern sound in a mix of background noise. Some tests check your ability to discern the difference between similar words. A thorough test will allow the audiologist to predict how helpful a hearing device may be.
Once these tests were done, my audiologist at Costco programmed a pair of demo hearing aids for me and let me walk around the store and chat with people to see if they were beneficial. (They were and he made the sale that day.) I’ve been an enthusiastic customer ever since.
If you are thinking about hearing aids, here is a table of features and benefits to help you decode the technical jargon.
The relentless march of new technology make digital devices obsolete in five years or less. Manufacturers have no incentive to make software and hardware “imporvements” compatible with legacy products. Consequently all of us have old laptops, old phones, and old tablets that won’t accept the latest software upgrades.
Our legacy devices still can do what we bought them for. But if we upgraded to newer operating systems, or later editions of Microsoft Office, they get slow and we get dissatisfied.
What to do? I’ve been experimenting with changing over from Windows and MAC operating systems to Linux. Linux is a non-proprietary system created by the community of developers who release their products for the common good, making them free for all non-commercial uses. It has evolved and branched into a number of different “flavors” that trace their digital genealogy back to the original Linux. Many of these easily install on Legacy devices.
On my old HP laptop that runs Vista, I installed Q4OS and was delighted to find it runs much faster. I added the freeware programs discussed in my earlier blog post and the computer is a servicable tool again.
I was not successful in installing Linux on Marguerite’s seven year old MacBook Pro laptop, so I simply replaced the harddrive with an inexpensive solid state hard drive which is eight times faster. I used Apple’s built in restore feature (Option-R) to put the original version of MAC OS10 back onto the comptuer, in effect making it the same as it was when she purchased it in 2012 – but eight times faster in booting up!
As with the Vista computer, I downloaded and installed the suite of freeware applications to make it fully functional and lightning fast. We’ll be giving that computer away. One of our friends will soon be happily surfing the web, corresponding, collecting photos, and doing all those everyday computer tasks without having to lay out big bucks for a new computer.
A friend asked me where I get the news. Mostly I read. I subscribe to several newspapers: NY Times, Wall Street Journal, Washington Post, LA Times. I also get The Economist, The Atlantic, and the New Yorker — all as digital online editions.
But there are many free sources of news and analysis. Here’s what I suggested to her:
The writer I most appreciate is Doug Muder, http://weeklysift.com.
Other writers you may enjoy:
Red for the Blue: https://mailchi.mp/redfortheblue/red-for-the-blue-what-the-right-is-saying-dogn1ba0da?e=78e666ec52
With major media like the NY Times you get the benefit of ethical editors vetting what they publish. Not so with blogs – you must be a critical thinker and savvy about bias and journalistic integrity. I pay for subscriptions because I want to support investigative reporting and editorial oversight.
You can read three articles in the times free each month before the paywall kicks in. If you subscribe to the blogs of your favorite columnists, you can track what they are writing about without buying the paper.
The Guardian still has no paywall.
For a general news overview check out News 360. It’s an aggregator that you may program for topics that interest you. Then when you open the App on your device, you will be served visuals and links to articles on the web.
There are many blogs that you listen to rather than read. These can be subscriptions that come to your computer or phone. Here is a survey article about how to get them.
Crystals can form in the fluid of the inner ear and cause benign paroxysmal positional vertigo (BPPV). When they stimulate the nerves that give us our sense of balance the room “spins.” While it’s happening our eyes dart (nystagmus) and we experience vertigo. You should always consult a medical professional and not try to doctor yourself or your friends. These movements may not be appropriate for some individuals. That said, here is what I have found in my internet research:
These three videos demonstrate how to deal with a BPPV instance at home.
A rose by any other name? These videos describe the moves differently but the goal is the same.
Most of us at Pennswood Village are lifetime witnesses to the explosive development of communications technology. When I was seven, my family didn’t have a TV set. It was a special treat when I was taken up the street to a neighbor’s house to watch Buffalo Bob and Howdy Doodie on a seven-inch black and white television. Blurry though the picture was, we were thrilled to sit on the floor munching cookies and sipping milk for that special half-hour.
Our house did have a phone. It sat on the “telephone table” in the hall at the foot of the stairs – one instrument for the household. A single pair of copper wires ran from that phone to a pole on the street and all the way downtown to the central office. There, telephone operators used switchboards to direct calls to other local subscribers, or to long-distance operators.
Over time, technical innovations allowed a single pair of copper wires can carry up to six simultaneous conversations, or a combination of voice and data. The clarity of the voice connection and the amount of data was diminished the further a subscriber lived from the central office. Bandwidth – the amount and speed of information transfer – was restricted by the inherent limitations of twisted pairs of copper wires.
The popularity of television entertainment made cable television networks attractive investments despite the high cost of building them. Unlike the twisted copper pair, a coaxial cable carries thousands of simultaneous streams of information: not just voice, but television and data as well. But cable also has inherent limits to the amount of information it can handle. Plus, it is better suited to delivering broadcast data to a large audience than it is to handling individual two-way communications.
Solid-state technology combined with digital networking overcame some of the limits of coaxial cables and made possible cable telephone service, movies on demand, and hundreds of channels of high definition TV. But the demand for these services today has reached the bandwidth limitations of coaxial cable. When the cable movie you are watching stalls, the cable internet is slow, or your cable phone drops out it’s usually because the cable network is maxed out. Like a highway at rush hour, congestion slows the flow of traffic.
Superior capacity (bandwidth) is why fiber optic cable is better to have than coaxial cable. In addition, fiber offers reliability, long service life, and immunity to electromagnetic interference. America’s cable network infrastructure is aging. Corrosion, deferred maintenance, and poor workmanship have degraded service in many areas. Fiber optic networks are to cable like new interstate highways are to aging conventional highways.
Our need for speed and capacity continues to grow. Bigger TVs with sharper pictures are coming. 3D and holographic TV are experimental. Scheduled broadcasting to many viewers is being supplanted by individual on-demand programming. Audiences are being segmented to target focused personal interests.
The demand for fast reliable two-way internet grows as YouTube and Facebook include streaming of live images. The tools to make presentations, movies, animations, and games are affordable for hobbyists and the Internet is both forum and marketplace.
For business and volunteer groups, interactive meetings and seminars are now affordable. Schools and colleges use the Internet for submission of homework, publishing of class materials, grades, and test results. Many people work from home all or part of the week relying on the Internet to stay current with their colleagues.
Having the advantages of fiber optic service will continue to grow in importance for present and future Pennswood residents. I can scarcely believe that in my lifetime we progressed from the telephone operator saying “number please” to technology that lets my wife watch daily color video images of our infant granddaughter. Why she can even call Key West to coo at her “live” on the wireless phone she carries in her purse. Verizon FiOS will let us continue to enjoy the ride in style.
We use the Internet extensively when we travel. Many of the things I do require a high-speed connection: searches, uploads of images and video content, downloads of reference materials, email with big attachments, and updates to the software. All too often the local Internet connection is shared and congested or capped at a very low speed.
Marguerite and I both have smartphones on the Verizon network. Since Verizon allows us to adjust our shared data limits from month to month we have bridged the intervals of poor local Internet access by using the personal hotspot feature on the phone. We buy the gigabytes of data we need. This can be expensive when Microsoft publishes a security update, or we have projects that hog data. It’s usually out of the question for streaming video.
When Verizon announced its “Unlimited” data plan it sounded perfect. Stream whatever you want, the ads promised.
Initially, it worked great, although it didn’t seem as fast as the metered connection we had before. But something went wrong with the Microsoft Office suite on my laptop and I had to reinstall the programs – think gigabytes of data. Heck, I thought, we have unlimited data. No worries here, I’ll just start the installation before we go to dinner and all will be well. When we got back, the message on the screen said, “You seem to have a slow connection. This may take a while.” It also showed a progress bar at about 15% – not so good – but the little wheel kept spinning, so I left it alone and used my iPad to do other work. The process continued into the night and by morning it was done.
But all was not well with our internet connection. In fact, it was as slow and erratic as the congested local wifi connections. Puzzling. The phone had good signal: five out of five bars. The service was “LTE” meaning that the data performance should be superior.
It turns out “unlimited” does not mean unmetered. A bit of online research revealed that there is a dirty little secret behind the unlimited claim. Technically if nobody else wanted to use the service it would be unlimited for me as a sole user. But the system gives priority to those whose usage is more modest – they go to the front of the line during periods of congestion. So my massive download of the Microsoft Suite probably put me dead last in line for the rest of the billing period.
The prospect of another week of the dismally slow Internet was not good news. My benchmark for acceptable service is consistent speed of at least two mbps download and one mbps upload. My present Verizon service was typically 0.04 mbps. I have some high-tech tools for measuring performance, and I could see all the symptoms of a highly congested channel and I just wasn’t getting through the higher priority traffic. Earlier, before my big download, the speed was a spritely 4 mbps download and 2 mbps upload.
I called Verizon customer service to ask why my unlimited was so, well, limited. The pleasant woman who took my call apologized and said it was just a matter of local congestion and denied that I was being penalized for over-use. When I said that I had found articles on the internet that exposed the deception, she began to talk very fast. And when I said I was going to replace my Verizon service with AT&T she started to negotiate.
I ended up switching from the unlimited plan to a metered plan. Magically my data speed jumped back to the 4 mbps level. Did the alleged “congestion” go away? Not likely. On a metered plan, it is in the Verizon company interest to have customers use data freely – and fast. I’m back at the head of the line again.
I live in a retirement community (Pennswood Village) and help with the technical side of lectures and stage performances. We own 16 lavalier style wireless microphones to amplify the voices of performers and speakers. Unfortunately, when pinned to the lapel these mics are too far from the mouth. Feedback and ambient noises become a big problem. If we had an unlimited budget, the solution would be to purchase lightweight over-the-ear microphones that hover just two or three inches from the corner of the mouth.
For many years the thespians have improvised by affixing the mic wire to their cheeks with surgical tape. Tape works, but perspiration and facial hair can sabotage the best efforts to keep the mic position. After the performance, it can be painful to peel the tape off. The mic wires get sticky and stained with makeup and old adhesive from the tape. It’s not a very satisfactory solution. Continue reading →