These three forms proposed by Weiser are characterised by being macro-sized, having a planar form and by incorporating visual output displays. These were also envisioned more as information appliances. If we relax each of these three characteristics we can expand this range into a much more diverse and potentially more useful range of ubiquitous computing devices.
Hence, three additional forms for ubiquitous systems have been proposed: . Smart devices are typically composed of a hardware layer including a radio that transmits signals , a network layer through which devices communicate with each other , and an application layer through which end users deliver commands. These layers often include the following characteristics:. It is proposed that there are two additional core types of properties for UbiCom systems: . However, it is hard to fix a closed set of properties that define all ubiquitous computing devices because of the sheer range and variety of ubiquitous computing research and applications.
Rather than to propose a single definition for ubiquitous computing, a taxonomy of properties for ubiquitous computing has been proposed, from which different kinds or flavours of ubiquitous systems and applications can be composed and described. The term Smart Device Environments has two meanings.
First, it can refer to a greater variety of device environments. Three different kinds of environments for devices can be differentiated: .
Second, the term Smart Device Environments can also refer to the concept of a smart environment which focuses more specifically on the physical environment of the device. The physical environment is smart because it is embedded or scattered with smart devices that can sense and control part of it. Although smart devices partially overlap in definition with specific types of appliance such as information appliances , smart devices are characterised and differ in several key ways.
First, smart devices in general can take a much wider range of form-factors than appliances. Second, smart devices support the ubiquitous computing properties. Third information appliances focus on remote interaction with computing environments that tend to be personalised whereas smart devices can also focus heavily on impersonal physical world interaction.
Four, the term appliance generally implies that devices are task specific and under the control of some embedded system or application specific operating system , whereas smart devices may support multiple tasks, e.
By the turn of the century he had built up a catalogue of 6 primary models with a number of variations thereof, and after being was laid off from his day job in ca he decided to go full time as a speaker manufacturer. Sadly Mr. Shinall was taken seriously ill in the fall of and passed away on the 16th of July at 65 years of age. Siare Noted French loudspeaker manufacturer, while primarily a manufacturer of high quality driver they where also active as an OEM , for instance in the early 80's they designed and manufacturer much of the classic Mission Electronics lineup et al.
Siemens became the largest electrical company in Europe and was particularly big in both the UK and Germany and remains to this day the pound gorilla of the European electric industry. The company was formerly a partner in the Telefunken group and currently has interest in anything from power stations to computer memory manufacture. Sierra-Brooks USA based company with production facility based in the Philippines that manufactured stock and custom wooden and fiberglass loudspeaker horns for use with home audio equipment rather than pro-audio products.
Run by Kevin Brooks who now runs Brooks Audio and Victorio Sierra who now runs 11 Horns , both manufacturing products largely similar to what S-B was making, timeline appears to be circa to but that is not really known.
Silvaweld Audio Lab. Was one of the new wave of Asian producers of valve based audio products and initially had a small line of single ended power amplifiers on the market but soon added pre-amplifiers, integrated units, push-pull configurations, phonographic pre-amplifiers and even a couple of OTL designs.
The Silvaweld products in general got very good reviews with the single exception of the remote controlled pre-amplifier, that was considered extremely good sounding but overpriced at the time.
The amplifiers from the company were designed by Mr. Having said that, Allnic Audio has offered some support and repair services for the Silvaweld product line. We have some information on the products the company made including Silvaweld Amplifiers but that is mostly on the minimal side. Sinclair had been writing technical and construction articles for the UK electronic press for some years prior to that and had already began supplying simple electronic kits of some of the projects for readers that would rather get a kit than making their own from scratch.
Initially SR sold small kit products usually uncased but as time wore on they became more professional in appearance and fully built products where eventually provided. Many of Sinclair's products where audio oriented and relied heavily on the technological wow factor as much as anything else, the Micro-6 kit from was as small as a matchbox, the Micro-FM was the worlds smallest FM radio and most if not all of the power amplifiers sold by the company where PWM devices, unheard of at the time.
A number of SR products where done using either sub-specification or end of line devices that the company bought cheaply from manufacturers of transistors and IC's, this sometimes meant that products that otherwise sold well had to be discontinued since the supply of the parts ran out, it also meant that many Sinclair products where often on the borderline of working properly, several of the amplifier products used class D topology had a reputation for doing evil things to the rest of your hi-fi system.
The Muntzing practices that Mr. They had a fix and I should return the unit, which I did. At the show I met Norm and one of his associates to let him know that it would be a while before I could fit the review into my schedule.
He graciously said I could take as long as I want. So Norm, I guess this is the preliminary review, and the final Only kidding, Norm. I don't want to be responsible for your heart attack. He then let me know that they will be producing a three channel amplifier in the Fall.
Thus, one can buy one three channel unit for the front channels, run long interconnects and place either a two or three channel unit at the back of the room for the two or three channels of surrounds.
This I find to be more intelligent than the five and six channel units out there where you have to run long lengths of speaker wire. Each has an Art Deco look chrome-black chassis with two sets of four LED's on the front to show power output from 0 to watts in 50 watt increments. The tube unit, which I am reviewing being a tubaholic, has a front window through which one can see the driver tube glowing.
On the rear is an IEC plug, three fuses, two sets of gold plated binding posts and RCA jacks, separated input volume pots, a ground lift switch, and a stereo-mono bridge switch. Damping factor and slew rate are very high yielding a frequency response of 2 to kHz. Each unit is burned in at the factory for five days.
There are separate volume pots for each channel, so if you are using them in a biamp mode you can separately adjust the woofer to the mids, or you can run your CD player, etc. Each comes with a graph showing distortion across the frequency band at full output for each channel. The units are built to high end standards, using high grade parts, a large torroid power transformer, and only moderate local feedback. The company has used similar circuitry for years to build professional cinema amplifiers which have to be rugged and reliable.
They are confidant enough in its indestructibility to offer a three year warranty. That's rare in the high end. In addition, at the end of the three years you can send the unit back, they will replace the tube, recalibrate the MosFETs, bring the unit back up to spec, and pay the postage back to you. See if any other company will do that. I have now had the unit in my system for two months, primarily using it on my center front horns. One channel to run the woofer to Hz and the other the mid-tweeter horn.
This is actually a great way to evaluate an amplifier as the horns are very efficient and will show every problem in the amps first watt. The woofer, when played hard, will pick up any power supply problems as there is no crossover between the speaker and amplifier.
Also, it is amazing how anomalies can be more easily picked up when listening to mono recordings as one is taking away much of the room masking that occurs with stereo playback.
For the first three weeks, I only used the unit to listen to central channel information from DVD's, and except for one problem the unit sounded great. That problem with low level 60 Hz hum, as mentioned above I'm sure it has something to do with my system or electricity. I took the previous unit which had more hum to my friend Kwame's house, where he uses high-sensitivity Beauhorn loudspeakers and there the unit was dead quiet.
Not a peep. And compared to his Korniff amplifier it was no slouch. Especially for a solid state vs. Here in my home I've tried multiple different interconnects, speaker wire, etc. My speakers are about 6 dB more efficient than Kwami's so that could be the reason I'm hearing it here. So again, don't hold this against the Smart and in the normal dB efficient system you probably won't hear it at all even with your head on the driver.
Zum kompletten artikel, reference ac cord, on headphone listening, audio perfectwave p10电厂ac再生器, blind listening test, intro audiostream, wavestream kinetic amps, i alarm clockom, blade in action, soundimage awards 2017