“Customer Requirements Determine our Standard”

Blue Tooth Designed products.

GGEC is a proud Associate member of Bluetooth

Unlike other speakers tethered to a computer via jumbled wires and power cords, GGEC manufactures wireless active-bass 2.1 stereo, as well as 2.0 solution speaker systems can be placed anywhere within 100' of your PC or Mac. Using world-standard Bluetooth wireless technology, the integrated speaker unit allows you to enjoy your digital music collection throughout your home, porch, or office not just at your desk.

Currently GGEC is providing Wireless Bluetooth Speaker systems to about 20% of the worlds population of Bluetooth Speaker systems sold.

Bluetooth enables our speaker devices to communicate with the computer system when they are in range. The devices use a radio communications system, so they do not have to be in line of sight of each other, and can even be in other rooms, as long as the received transmission is powerful enough.

For more higher end systems we have now produced Bluetooth systems that Daisy chain via wireless, creating a multi Bluetooth room capability.

Bluetooth is a standard and communications protocol primarily designed for low power consumption, with a short range (power-class-dependent: 1 meter, 10 meters, 100 meters) based on low-cost transceiver microchips in each device.


Telecommunications and Multimedia

Telecommunications – The conference call

In larger organizations, getting things done often requires contributions from many people. Audio conferencing is an efficient, cost-effective way to keep everyone "in the loop." Unfortunately, with most audio conferencing systems, the more people that participate in a conference, the more technology gets in the way of productivity. GGEC and its customers have worked through this problem by providing speakers for this product line with uncompromised accuracy.

GGEC speakers are in use in 90% of Business level desktop phones found in the USA, and 70% of all phones in consumer use in the USA. They are ideal for day-to-day group collaboration in ad hoc meeting rooms, breakout rooms, and small to medium conference rooms, or even one’s kitchen. Full-time 360-degree coverage assures that everyone in the room can be heard.

Full Duplex Conferencing Technology – talk and listen at the same time

Our customers offer digital and IP-based full duplex speaker systems for desktop phones for large and small conference rooms and consumer use. Full duplex technology means simultaneous two-way transmission. There is no changeover from incoming to outgoing, thereby eliminating the clipping and hollow sounds associated with conventional half-duplex speakerphones. The speaker drivers that GGEC produces must have tight frequency response windows with little or no variation so they can be consistently coupled with the digital electronics associated with full duplex systems. In the event a driver has a variation of frequency response other than what is defined in the digital code of the DCP, feedback can occur.

Therefore the performance of our drivers for this application must have little to no variation from driver to driver. This is a very stringent requirement in regards to producing more than 7 million speakers for this application a year

Full Duplex operation – Why is the speaker is so important?

A full-duplex algorithm allows both parties to talk at the same time and only cancels the returned echo. While the full-duplex algorithm provides a more natural conversation without cutting off any party, it is more susceptible to impairment in the echoed audio path. The performance of a full-duplex algorithm depends on the linearity of the echo signal. Non-linearities in the audio path degrade the voice performance.

A key performance goal for GGEC Engineers is to create voice communication in a more natural mode, and providing drivers with “Fixed” frequency responses. The Driver cannot vary from driver to driver so that the customer can write the digital algorithm- transformed into written digital code. These are the building blocks to achieve a full-duplex algorithm. Since digital code is an exact transformation of the analog response, variation is not accounted for in the digital code.


Echo return

Echo return is the amount of reflected audio from the speaker picked up by the microphone. The reflected signal is composed of the direct acoustic coupling (the amount of audio the microphone picks up directly from the speaker) and the audio reflections from the surfaces in the enclosure and room. The goal of the speakerphone designer is to minimize the echo return. This is done in part through the plastic enclosure design, the other is using speakers with exact frequency response performance. It is impossible to entirely eliminate echo, hence the need for an acoustic echo canceller (AEC). To achieve the highest performance, an AEC tries to minimize this returned signal.

Gain (amplitude control) in the echo path – How the Telephone manufacturer balances Speaker and Microphone

The speaker and microphone gain pads affect the echo path.

The gain is a measure of the ability of a circuit (the amplifier) to increase the power or amplitude of a signal. It is defined as the mean ratio of the signal output of a system to the signal input of the same system.

These gains are necessary and are set appropriately to achieve high performance echo cancellation. For optimal performance, an AEC should be designed based on its ability to cancel the highest level of acoustic echo return without freezing adaptation (it should continuously track changes in the echo path) or using switched attenuation (it should not fall back to half-duplex).


Distortion

Distortion in the acoustic echo path is a major contributor to poor acoustic echo cancellation. Once the echoed audio signal is corrupted, the AEC has no way of modeling the echo path and canceling echo. There are many contributors to distortion, and the speaker’s distortion is one of the design variables that must be eliminated.

How does a GGEC speaker solve this problem?

GGEC engineers address the Distortion issues in the speaker design to allow the (acoustic echo canceller) AEC to “Blueprint” the exact distortion, thus eliminating the echo.
GGEC Speaker design is critical to achieving high performance hands-free operation. The maximum speaker rating is usually given at a distortion rating of 10% total harmonic distortion (THD). For good quality AEC performance the THD should be less than 2%. Generally, 2% THD occurs at approximately half the maximum power rating. If the system design requires a 1W speaker driver then a 2W speaker or higher should be designed.

We at GGEC prefer to design our drivers for this application as Fill bandwidth drivers (Wide Bandwidth) whereas we increase the frequency bandwidth over conventional drivers for this application.

This is why 3 of the largest telephone manufacturing companies in North America specify GGEC designed and manufactured drivers for their systems. GGEC supplies 100% of these drivers to these companies.


Clipping in the speaker driver can also severely affect the AEC performance. It is very noticeable and can be adjusted by the user accordingly. What is less obvious is the non-linearity as the driver approaches clipping. At GGEC our engineers take care to ensure the speaker can be matched with the driver for the required power. Therefore the speaker must be designed for less than 2% THD. This ensures that both the speaker and driver are operating in the linear range.


Multimedia

Laptop and Desktop computers

GGEC is currently providing speakers and speaker systems to some of the largest computer manufacturers in the world. These customers rely on GGEC’s unsurpassed quality and reliability to equip their computers with quality acoustics while not having to participate in the acoustic design process. Some of the latest products we have supplied are actual Subwoofer modules with acoustic ports. This is to extend the lower frequency range of laptop systems. We produce millions of these speakers per year and are shipped directly to the customer for final assembly into the finished product.



“We get it”