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Radio Currents Online - Sep 27 - Oct 3, 2004
Radio technology news updated as it happens.
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Clear Channel: 5kHz for AM
Cincinnati – Sep 29, 2004 – A memo sent to the Clear Channel Radio engineers from Jeff Littlejohn, senior VP of engineering for Clear Channel, spells out a plan for all the Clear Channel AM stations to reduce their audio bandwidth to 5kHz or 6kHz, depending on the station's format. Littlejohn based the decision on his own listening experience during IBOC tests with WLW (700) Cincinnati and WOR (710) New York.
An excerpt from his memo:
During those tests, we limited both stations to 5kHz audio bandwidth and then turned on and off the IBOC carriers at 1-minute intervals. The result was pretty interesting! When I tuned to 710 AM, I heard WOR-AM's skywave crystal clear! Never in the dozen years of living in Cincinnati had I heard WOR's skywave signal. It had always been obliterated by the sidebands of WLW.
Next, I tuned to WLW 700, I couldn't perceive any audible degradation by limiting the audio to 5kHz. Suddenly, it struck me that radio had lost the battle that was fought in 1987 through 1991. That was the time period when we argued with the CEA, [the] NAB and [the] NRSC about a couple of new AM Audio standards, NRSC-1, NRSC-2 and NRSC-3. I remember complaining about how much limiting our audio sidebands to 10kHz was going to degrade the performance of AM. NAB wanted to retain 15kHz audio, CEA wanted us to reduce our audio bandwidth to 5kHz. In the end, we settled on 10kHz audio and later the FCC adopted the standard as the new bandwidth requirement.
The goal of NRSC was laudable and was intended to result in wider bandwidth receivers, but the fact is that nobody ever made more than a handful of these wider-bandwidth receivers. Instead, the receiver manufacturers continued to reduce the audio bandwidth of AM receivers to eliminate the "chatter" caused by the sidebands of adjacent channels. The result is that an "above average" receiver today has audio response that is less than 4.5kHz. In fact most have audio response that is down 10 to 12dB at 5kHz, and the roll off can start at around 2kHz.
Littlejohn's memo goes on to question the logic of transmitting a 10kHz signal when few if any listeners can receive anything above 4.5kHz. He cites that reducing the audio bandwidth will improve modulation efficiency, reduce interference to first-adjacent channels, and reduce the noise floor in the bandwidth-limited receivers.
Because of this, Littlejohn "can find no good reason to maintain 10kHz audio bandwidth" and that there are "substantive benefits" to stations reducing their audio bandwidth to match the passband of AM receivers. He has called for a standard operating practice for all Clear Channel AM stations.
All stations with modern audio processors will reduce their bandwidth to 5kHz, except for those stations with music-intensive formats, which will be reduced to 6kHz.
Stations that do not have a modern processor that is capable of the reduction in audio bandwidth will be given favorable review to any request for a replacement audio processor.
Littlejohn adds, "It is true that AM HD Radio is going to require that we reduce our audio bandwidth to 5kHz...to properly implement that technology. However, this change has nothing to do with HD Radio. It's the right thing to do for AM analog radio service. HD Radio just happened to point out that the benefit existed."
Littlejohn is the co-chairman of the NRSC's AM subcommittee, and in his memo he states that he will propose this standard practice among all AM licensees. He wants Clear Channel to "be the leader in this effort to clean up the AM analog service."
Comments have already risen regarding this action. Some comments received at Radio magazine don't agree with Littlejohn's assessment of an unnoticeable impact from the reduced audio bandwidth. Other comments don't believe the claim that the move is irrelevant to the HD Radio analog signal requirements, and that this is one way to make analog AM sound worse so that AM IBOC will show a marked audio improvement over analog.
There are merits to what Littlejohn proposes, but as he pointed out, the idea is not really a new one. It will cause some stir for a few days and maybe weeks, but the buzz will likely die down soon.
New York City Updates Public Communications
New York - Sep 28, 2004 - A recent article in Government Technology details the improvements that have been made in New York to better disseminate information to the public during an emergency.
One part of this upgrade was some changes to the local EAS plan. Another change was the creation of six facilities in three boroughs where city officials can conduct news conferences. These facilities are connected to media outlets via fiber optic cables.
Michael Bloomberg, the mayor of New York is quoted in the article, and he acknowledged the efforts of the broadcasters involved, specifically Kevin Plumb of WABC, Mark Olkowski, CPBE, of WINS and Richard Novik of the New York State Broadcasters Association.
The EAS revision is based on agreements between the city, WABC-AM, WFAN-AM, WINS-AM and WCBS-AM. The mayor can activate the city EAS from an EAS device itself or by phone.
The city's EAS plan was approved by the State Emergency Communications Committee on April 29, 2004, and was accepted by the FCC. The city will also install special EAS equipment at the 911 call center and the 311 citizen service.
Plans are in place to activate additional communications sites across the city that can immediately broadcast to the media.
The Board of Directors of the Radio Advertising Bureau recognizes the efforts of all Radio broadcasters employing IBOC high-definition radio, technology that brings a new and improved digital sound to radio stations nationwide.
Further, the board encourages the same broadcasters continue to educate their listeners on the benefits of the new digital sound.
The RAB has nearly 7,000 members.
Radio Soft's Frequency Finder Selected for National Database
Demorest, GA - Oct 1, 2004 - Radio Soft's company, Frequency Finder, has been selected by the FCC and the National Telecommunications Information Administration (NTIA) to provide a national database and registration management for private companies and state and local governments that want to use the high-capacity wireless spectrum, millimeter wave.
Providing several applications for the private sector and state and local governments, millimeter wave offers high speed, point-to-point wireless data links that can handle heavy loads. Users will share the spectrum with government facilities, such as military bases, so it is imperative that frequencies are accurately registered and carefully checked to eliminate interference, which is where Frequency Finder becomes involved.
Radio Soft is one of three vendors who will participate in the database management program. Users who wish to register millimeter wave link frequency can obtain a nationwide millimeter wave license by filling out a simple online FCC form. Once locations for the wireless networks are chosen, users will visit a registration site to complete the process.
Audemat-Aztec Licenses HD Radio Technology
North Miami Beach, FL, and Columbia, MD - Oct 1, 2004 - Audemat-Aztec has licensed Ibiquity's HD Radio technology for inclusion into Audemat-Aztec's radio test and monitoring products. As a result, Audemat-Aztec will be able to further assist AM and FM broadcasters in the initial transition to digital and maximize the benefits of their digital signals by offering mobile products capable of measuring coverage and analyzing quality of HD Radio reception.
Audemat-Aztec states that it received many requests from U.S. customers to develop a mobile RF field strength meter to measure the coverage and analyze the quality of HD Radio reception. This product, which has been named NavIBOC, is being designed and will be available for sale at NAB2005.
Klark Teknik Celebrates 30th Anniversary
London - Sep 30, 2004 - Klark Teknik celebrated its 30th anniversary at PLASA 2004. Founded as Klark Teknik Research by brothers Phil and Terry Clarke in 1974, the company quickly became known for their approach to design and development.
The first digital delay and reverb units were created in Klark Teknik Research’s laboratory, however, it was the company's concepts for equalization devices that made the company famous. Their earliest designs eventually matured into the DN360, that celebrates its 20th year.
Arbitron and VNU Sign Agreement
New York - Sep 29, 2004 - Arbitron and VNU have agreed to jointly explore the possible development of a new, national marketing research service that collects multi-media and purchase information from a common sample of consumers. The service will be designed to enable a better understanding of consumer exposure to advertising on multiple media and the link to their shopping/purchase behavior. The ultimate objective would be to provide advertisers with an enhanced ability to determine the return on investment for their marketing efforts. Procter and Gamble will collaborate with the two companies to ensure that the service properly addresses the needs of marketers.
The service would consist of a panel of participants who would be offered incentives to voluntarily carry Arbitron's Portable People Meter (PPM), a small, pager-like device that collects the volunteers' exposure to multiple media sources. Data on consumer preference and purchases for a wide range of services and products would also be collected from panelists, electronically and via surveys, with some households being part of AC Nielsen's Homescan consumer panel, which currently tracks packaged goods purchases. Data would be collected in aggregate form to provide a holistic understanding of participants' media interactions and their resulting shopping and purchase behavior.
P and G has agreed to collaborate with VNU and Arbitron in the development of this new research service, as P and G has long been interested in identifying new consumer-centric approaches for better understanding and reaching consumers in appealing ways.
Arbitron and VNU emphasized that the service would be separate, distinct and designed differently from any service for TV and radio ratings.
PMI Audio Group
1845 W. 169th Street
Gardena, CA 90247
The company's Web info is unchanged: www.pmiaudio.com.
PMI's new location also houses Joemeek Studios. Based around a Pro Tools HD Accel system, the studio will be used to test products. PMI is the distributor for Joemeek, Studio Projects and Toft Audio Designs.
Burk Technology Releases New ARC-16 Firmware
Littleton, MA - Sep 30, 2004 - Burk Technology has released new firmware for the ARC-16 transmitter remote control system. Firmware version 5.6 offers faster baud rates for digital communication links, providing more responsive site-to-site communication, especially with multiple remote sites.
Peter Burk, president of Burk Technology, noted that that supporting 4800 and 9600 baud benefits the performance of the ARC-16 without requiring more than one T1 slot. In some installations, data bandwidth is at a premium, and Burk wants to offer an economical choice.
More information: www.burk.com.
Mediaguide Launches Monitor Airplay Reporting Products
Berwyn, PA - Sep 28, 2004 - Mediaguide has introduced an enhanced product portfolio. Mediaguide's broadcast monitoring network provides real-time measurement and reporting of nearly 2,500 radio and television stations' programming across more than 200 major U.S. markets.
The new Mediaguide Monitor product lineup includes Music Monitor, which is specifically designed for record label managers, promoters and music distributors and Artist Monitor, designed for independent artists and those who manage them.
Developed specifically for broadcasters, Station Monitor provides radio program directors and station operators a tool to better understand competitor, tastemaker and format-wide airplay trends to improve their own programming.
Song Monitor, designed for individual songwriters, composers and music publishers, tracks the performance of music compositions.
The Mediaguide Monitor platform features weekly airplay charts covering top songs and albums across college, non-commercial and commercial radio. Rankings are based on the widest panels available in the industry to give the most accurate picture of each format's most popular artists and recordings. Through partnerships, Mediaguide will also make these charts available to the broader media and entertainment industries and general public.
Mediaguide is a joint venture of ASCAP and Connexus.
The 8x2 8002MCB features eight-channel, dual bus mic/line mixing, compression and limiting, actively balanced inputs and outputs, a dual-function LED VU meter, phantom power, a headphone out and XLR or Phoenix-style connectors depending on model.
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