How the Bose Wave Radio makes Big Sound

How the Bose Wave Radio makes Big Sound

When we think of replacing our old CD player with a newer version, an increase in its size becomes an obvious factor. With there being no other choice, most of us tend to compromise with the issue. After all, it’s the power and quality that most of us look at, and the size factor becomes of little importance.

However, there are folks who are very choosy and rather expect all features of a product to be presented intact, without compromising a bit. Moreover in offices or rooms with limited space, bulkier sound systems are definitely a non-starter.

Taking this into account, and after some relentless research and development, the engineers at BoseTM came up with an innovative “Acoustic Waveguide Speaker” concept for their compact Wave radio. By making use of the idea, an audio system could be made to inherit all the outstanding sound qualities of its “big brothers” and yet could be enclosed inside a dramatically smaller cabinet, which could easily sit at the corner of your office table.

Way back in 1983, the first Bose radio with the above state-of-the-art technology was introduced. It became popular as the first-ever table top hi-fi radio. Further enhancements in the system included the introduction of a tape cassette player in conjunction with the radio; however, in the year 1993, the company produced its first acoustic audio system having a CD player built-in. This was considered as one of the biggest achievements for the manufacturer because of one major reason: CD players, as we all know, tend to become sloppy and respond poorly to vibrations. You can witness the wobbly response by listening to a CD Walkman while jogging.

When a CD player is enclosed inside a compact area, surrounded with powerful speakers, the chamber easily becomes a strong vibration zone, greatly affecting the CD player’s output due to the speaker cone’s movement. The problem becomes more aggravated at lower frequencies, which force the speakers to displace more air inside the enclosure, thus inducing greater vibrations to the CD mechanism.

The Bose Acoustic speaker technology could easy circumvent the above drawback and produce crystal clear Hi-Fi output as desired by the user, irrespective of the frequency or the volume level.

So what’s the magic behind the technology? How was the challenge of obtaining hi-fidelity, high power output even from with smaller cabinets met? How does the Bose wave makes it sound? Let’s find out.

Internal Mechanism of the Bose Waveguide Radio - X-ray View

The Technology

It took the team composed of Dr. Amar Bose and Bose senior research engineer Dr. William R. Short almost fourteen years to develop this state-of-the-art concept. Their innovation can be understood with the following explanation:

We all know that when a speaker is mounted in an enclosed channel or tube, the cone movements act as a wave guide, producing higher outputs than the actual output from the speaker. The Bose engineers quickly discovered that the above wave guide phenomena could be effectively utilized for operating speakers with utmost efficiencies.

It was understood that by incorporating a wave guide, smaller speakers could be used for acquiring richer outputs, irrespective of the volume of the music. However it was easier said than done: the concept definitely required some serious calculations and a lot of trial and error experiments to be done before it could actually be implemented.

The actual theory is a trade secret and has been patented, and therefore all the details cannot be revealed here, but the following points can make the idea considerably clear to us, as far as the operation is concerned:

At Bose, the engineers started calculating the exact area of the wave guide and the way it could be accommodated inside smaller enclosures. This led to the development of a long channelized waveguide structure, very complexly woven into bends and curves. This enabled the vibrations from the speaker to pass across the entire waveguide in such way that the final output not only retained the actual clarity of the audio, but enhanced it with additional depth and theater-like experience. The careful calculations involved with the waveguide design helped the inventors to design much smaller wave radios than its predecessors.

In the CD players, for the best possible results, the CD mechanism was placed at the center, with the Bose waveguide structure coiling past it. The design ensured maximum efficiency for the audio output, keeping the CD mechanism well isolated from any residual vibration imposed by the waveguide.

The electronics involved is also well optimized in a Bose Wave radio, where the tonal balance of the output is kept within the best possible human hearing perception by automatically compensating levels whenever the volume is increased or decreased.

More technically the concept can be summarized as follows:

When a speaker vibrates, the vibrations are transformed into audible sound waves. However with conventional systems, the rear of the speakers are shut off or covered up, so only the vibrations generated at the front of the speaker become audible. The Bose wave guide system intelligently channelizes the rear vibrations of the air from the speaker so that these vibrations are also effectively transformed into audible sound. The intricately calculated structure further enhances this output, producing outstanding sound output with minimal space utilization.

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