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When Stan Getz and Joao Gilberto turned “The Girl from Ipanema” into a classic LP, they probably never realized that the work they were doing would be the standard by which many turntables would later be judged and that’s why a turntable such as the Audio Technica AT-PL60 Fully Automatic Belt Driven Turntable is still a hit after all these years.

It is true the digital audio crowd has proclaimed the end of the LP and pressed recordings many times over, yet, if you are a real audiophile, the only way — only way — one can listen to good music is with a standard turntable. Fortunately, the audio industry does know that it takes all kinds of source material to keep audiophiles happy, so they provide as many ways as possible to get source material to the speaker cones. They may use simple binding posts or screw-on binding posts or the clip-style (push the button and insert the wire into a set of teeth). Even the good, old-fashioned RCA-style plug has its place in an audiophile’s speaker domain, which is why true purists can get the richness that LPs and 45s still bring to music.

It is true that digital audio is great and when you jam those iPod earbuds down tightly into your earlobes you hear many bright highs and lows, but there is still a lot to be said for putting on a classic pressing of an LP — Chicago’s “White Album” comes to mind — and listening through a good set of speakers (that’s one good thing about speakers, as long as the input source material can go from digital to analog or analog to digital, the speaker cones don’t care what is driving them, they just reproduce the sound).

There’s a certain richness that you only get from a good pressing of an LP that digital audio, for all of its ability to repeat sound exactly, just can’t match. We’ve tried listening both ways and still do prefer the output from a turntable like the Audio Technica because of the richness we’ve talked about.

Yet, even Audio Technica, which still uses belt drive, has been overtaken by the digital audio world in that it the AT-PL60 includes a switchable phone preamp and inputs so that you can hook your turntable directly to your home PC.

One of the features we like about the turntable is its dual magnet phone cartridge which not only helps audio input but, since it is a cartridge, is replaceable when the stylus wears out (digital audiophiles will point out that one doesn’t have to replace a CD or DVD unit after a given number of plays and that the digital units will deliver clean precise audio until they fail, but remember when they fail, you do have to replace the whole CD or DVD and not just the stylus).

The Audio Technica is a two-speed turntable 33 1/3 and 45 and the platter itself is aluminum-based so it will remain straight and balanced. It also has some fine Wow and Flutter specs. Wow and Flutter is less than 0.25 percent (WTD) at 3 kHz. The S/N ratio (signal-to-noise) is better than 50 dB (DIN-B).

On the output side, the phono preamp has is 2.5 mV at 1 kHz, at 50 cm per second. The line-in preamp has great specs of 150 mV at 1kHz, at 5 cm per second. Phono pre-amp gain is a nominal 36 dB.

A compact turntable, the Audio Technica weighs only 6.6 pounds and is 14 by 4 by 14 so it won’t take up much space in any home entertainment center. Accessories included with it include dual RCA-style female to standard 3.5 mm stereo male adapter; and a RCA-style female to female adapter cable, as well as the 45 mm center spindle for 45 rpm pressings.

Streaming multimedia is a form of multimedia, which itself is media that uses different forms of content. Combinations of text, audio, still images, animation, video, and interactivity content forms are typical modes of multimedia presentation.

The streaming variant is being sent, in a continuous flow, to the user of the content by the streaming provider. In this context, examples of the content stream include audio and video.

The streaming refers to the method of delivery of the content flow rather than to the nature of the content. Apart from telecommunications networks, most systems for delivering content are either streaming, such as radio and television, or non-streaming, such as audio CDs, video cassettes, and books. The term ‘to stream’ means, quite simply, to deliver media in this particular manner.

History

The first attempts were made, in mid-20th century, to display media on computers. However, due to the high cost and very limited capabilities of computer hardware at that time, development did not proceed at any pace for many years.

By the 1990s, personal computers had become sufficiently powerful to display a variety of media forms. The main technical problems associated with streaming at that time were:

Having sufficient CPU power, which refers to the central processor, that can execute computer programmes, and also bus bandwidth, which is the capacity of the system to transfer data over a connection, in order to support the required rates of data flow.

Creating low latency, which allows delays too swift for human detection between an input being processed and the corresponding output providing real time characteristics, interrupt paths in the OS, or operating system, to prevent buffer underrun, which occurs when a buffer, which is a storage device used to compensate for a difference in rate of flow of data between devices used to communicate between two devices or processes, is fed with data at a lower speed than the data is being read from it.

However, computer networks had still not developed fully, and so media content was normally processed over non-streaming channels, such as CD ROMs.

Between the late 1990s and into the next century, there were significant advances in the internet, such as:

An increase in network bandwidth, especially in the last mile, which referred to the final leg of delivering connectivity from the communications provider to a customer.

Greater access to networks, especially the internet.

The application of standard protocols and formats, such as TCP/IP, HTTP, and HTML.

Significantly greater commercialisation of the Internet.

With the advent of powerful home computers and advanced operating systems, these advances in computer networking enabled streaming media to become a practical and affordable proposition for the nation at large.

Another advance was the introduction of stand-alone Internet radio devices, which are hardware devices that receive and play audio from internet radio stations or the user’s PC or other embedded media servers. For the first time, this provided listeners with the ability to listen to audio streams without the requirement of a PC.

In general, multimedia content is large, so media storage and transmission costs are still significant. In order to compensate for this, media is generally compressed, such as in a ZIP file format, which provides compression, and also acts as an archiver, storing many source files in a single destination output file, for both storage and streaming.

A media stream can be either on demand or live. In the case of on demand streams, the content is stored on a server for long periods of time, and is available for transmission on request. Live streams, on the other hand, are only available at one particular time, such as in a video stream of a live sporting event.

Latest wireless audio gizmos such as iPods, wireless headphones and cell phones support new wireless protocols. These protocols are supposed to eliminate the cord and provide perfect high-fidelity audio. We will examine some of the most recent devices to figure out which applications they work for.

Several products come with wireless already built in while others, particularly streaming audio products, frequently have optional wireless functionality. Modern cell phones and MP3 players already come with support for wireless. iPhones and touch-screen iPods, for instance, have Bluetooth and WiFi.

The Bluetooth protocol is a fairly low-cost solution. Still, its limitations have an effect on high-quality audio applications and are often overlooked.

1) Short range

Bluetooth usually just provides a 30 foot range. This is sufficient for single-room applications. On the other hand, this limitation does not permit multi-room streaming utilizing Bluetooth.

2) Audio compression resulting from limited data rate

Bluetooth will use audio compression because it does not reliably offer a high-enough data rate for uncompressed audio. The audio will be degraded to some degree as a result of the audio compression. For this reason higher-end audio equipment generally does not use Bluetooth wireless audio.

3) Signal latency

The signal broadcast via Bluetooth will undergo a slight delay of no less than 10 ms. This is mostly due to the audio compression. While being uncritical for MP3 players, this delay may be a dilemma for video and other real-time applications.

4) No support of multiple headphones

Bluetooth is relatively limited in regard to supporting streaming to multiple headphones. Streaming to multiple headphones is useful for numerous people wanting to listen to the same transmitter. This is less of a problem for MP3 player applications.

Uncompressed audio streaming is supported by WiFi. WiFi is a very widespread protocol. Yet, WiFi also has limitations regarding simultaneous transmission to several receivers. Due to the high availability, WiFi is suitable for streaming audio from a PC. However, WiFi products have relatively high power consumption. Because of this wireless headphones usually do not utilize this technology.

Wireless speakers and wireless amplifier products for home theater speakers typically utilize their own proprietary protocol. Entry-level wireless headphones and speakers usually still utilize FM transmission which offers low cost but is prone to noise and audio distortion.

More advanced wireless protocols are based on digital formats which eliminate audio distortion and incorporate sophisticated features including error correction to cope with interference from competing wireless devices.

Latest-generation wireless amplifiers employ uncompressed audio transmission. Recent protocols also allow streaming to an infinite number of receivers. This allows whole-house audio distribution.

Some of these protocols support low-latency audio transmission which ensures that the audio of all speakers will be in sync in a multi-channel application. Wireless audio transmitter products typically operate at 2.4 GHz or sometimes in the less crowded 5.8 GHz frequency band including Amphony’s wireless audio devices.

Wireless amplifiers are available with different levels of audio quality, power consumption and standby power. Getting a high-quality low-distortion amplifier is fundamental for good sound quality. Digital Class-D amplifiers offer high power efficiency of a minimum of 80%. They also have low standby power, typically less than 5 Watts. This reduces heat and keeps them cool during operation. Some digital amplifiers, however, have fairly high harmonic distortion. It is vital to select a wireless amplifier with low audio distortion. This will ensure good sound quality. High-quality amplifiers have audio distortion of 0.05% or less.

Did you know you can speed-listen to 60 minutes of audio in 30 minutes or less with full comprehension using special speed-listening software? You can even go faster with a little practice and blast through an hour of audio learning in 20 minutes or less saving you hours and hours of time.

If this is your first exposure to the concept of speed-listening to your audio learning you may be a bit skeptical like I was. You may also have doubts speed-listening to audio learning materials will work for you too. I can’t blame you.

The first time I heard about speed-listening I was skeptical and doubtful it was for real too because the only faster audio I ever heard was Alvin and the Chipmunks at Christmas time or when as a kid I sped up the old record player for kicks!

Using FasterAudio speed-listening software is the secret to effective speed-listening because it speeds up your audio without changing the pitch so the voices sound normal just faster. This is why you can accelerate your audio 2X and faster with full comprehension.

What’s cool about using the FasterAudio software is you can convert your audio files into an accelerated format Mp3 which is easily transferred to your iPod or any Mp3 playing device. This lets you maximize your audio learning time whenever you are away from your PC or Mac running Parallels.

Getting Started With Speed-Listening

When I first tried FasterAudio speed-listening software I set the audio to 125% of regular speed. After just a few minutes at 125% I accelerated my audio learning up to 1.5 X of regular speed. Not only was I able to listen to the accelerated audio with ease, but was doing so with full comprehension. It was easy and fun. Really amazing.

Then I did the math. At 1.5X regular audio speed you save 20 minutes for every 60 minutes of audio learning, but I wanted to listen faster. After about 1hr of listening at 1.5X I went to 1.75X of regular speed. It took another hour or so to get used to listening at 1.75X speed with ease.

My goal was to cut my audio learning time in half so over the next few days I used FasterAudio to slowly increase the speed of the audios I was listening to. It wasn’t long before I hit 2X speed and reached my goal. Then I heard about people who speed-listen at up to 4.5X of regular speed. This motivated and challenged me to keep pushing my listening speed faster and faster. I have since reached 3.5X of normal listening speed and continue to push myself.
That said, 1.5X of normal speed is quick and easy to reach and will save you hours of valuable time if you listen to audiobooks, podcasts, home study programs etc.

Bottom line your first goal should be to get comfortable with 1.5X (most people have no trouble reaching that) and then work at doubling your listening speed so you cut your audio learning time in half. Then keep pushing yourself to go faster.

You can check out FasterAudio speed-listening software at this link and experience speed-listening for yourself live on the website.

The latest series of wireless audio transmitter devices promises streaming of music throughout the home without limits. We will look at various products and technologies to find out in how far these devices are effective for whole-house audio applications and what to look out for when buying a wireless system.

Infrared wireless audio devices are restricted to line-of-sight applications, i.e. only function within a single room because the signal is sent as infrared light which can’t penetrate walls. This technology is often found in wireless speaker kit products.

RF wireless music devices broadcast the music signal via radio waves. These radio wave signals can without difficulty go through walls. The signal is broadcast either by utilizing FM transmission or digital transmission. FM transmission is cheap but quite prone to static, audio distortion and susceptible to interference.

Digital wireless audio transmitter devices, such as products from Amphony, make use of a digital protocol. The audio is first converted to digital data before being broadcast. This method guarantees that the audio quality is fully preserved. Some transmitters utilize some form of audio compression, such as Bluetooth transmitters, which will degrade the audio to some degree. Transmitters which send the audio data uncompressed will achieve the highest fidelity.

Wireless LAN (WLAN) products are practical when streaming from a PC but will add some amount of latency or delay to the signal because wireless LAN was not originally designed for real-time audio streaming. WLAN receivers ordinarily require buying a separate LAN card to be plugged into every receiver.

Powerline products send the audio via the power mains and offer great range. They run into problems in homes where there are individual mains circuits in terms of being able to cross over into another circuit. Also, these products build in a delay of a number of seconds to safeguard against transmission errors during power surges and spikes which prevents their use in applications where the audio from wireless loudspeakers has to be in sync with other non-wireless speakers or video.

Here are some recommendations for picking the optimum wireless audio system: Try to find a system that can run several wireless receivers from a single transmitter. Ideally an unlimited number of receivers should be supported. That way you don’t need to buy extra transmitters when you start adding receivers in several rooms of your house. Some devices have some form of error correction built in which will help guard against dropouts in case of strong wireless interference. Choose a digital RF audio transmitter to guarantee that the audio quality is preserved. Make sure the audio delay is smaller than 10 ms if you have a real-time application such as video.

Select a transmitter that has all of the audio inputs you need, e.g. speaker inputs, RCA inputs etc. Get a wireless system where you can buy separate receivers later on. You should confirm that you can get receivers for all the different applications you have. Such receivers may include amplified receivers for passive speakers or line-level receivers for active speakers. Select a transmitter that can regulate the audio volume of the input stage. This will give you the flexibility to connect the transmitter to any kind of equipment with different signal levels. Otherwise the audio may get clipped inside the transmitter converter stage or the dynamic range is not fully utilized.

Check that the system provides amplified receivers with a digital amplifier to ensure high power efficiency. This will help keep the receiver cool during operation. Also, make sure the amplifier provides low audio distortion. This is vital for good sound quality. Verify that the amplified receiver is able to drive speakers with the preferred Ohm rating and that it is small and easily mountable for simple installation. Products using the less crowded 5.8 GHz frequency band will normally have less trouble with wireless interference than 900 MHz or 2.4 GHz products.