Q-It-Up-Logo-sep95This month’s Q It Up gets part 2 of our responses as we focus on the use of the Internet to send and receive audio for on-air broadcast.

Q It Up: The use of the Internet for delivering commercials to radio stations is here, with companies such as SpotTaxi.com, SlingSpot.com, AudioSonix.com, and SpotTraffic.com all vying for a piece of the new pie. The common thread is the use of MPEG compression to reduce the audio files to sizes more compatible with today’s Internet connection speeds. There is a concern among some radio engineers that the use of MPEG compression in conjunction with existing audio chains that utilize other digital compression algorithms may cause some degradation of the quality of the audio, resulting in a potential tune-out factor. What are your thoughts on this, and on the use of the Internet for spot delivery in general? Is your Chief Engineer for or against the use of MPEG files on the air for commercials? Is your station planning to utilize this technology? Feel free to add any other comments you have on the subject.


AudioSonix-LogoRichard Stroobant [bigdick[at] cjay92.com] CJAY/CKMX, Calgary, Alberta, Canada: We have been using MP3 technology for spot delivery for about a year now, and I have had no problems at all using MPEG compression. After all, that is how DGS/DCI has been sending their spots to us for years now (using mp2). I have done several A/B comparisons, and after listening to the commercials on the radio (after it goes thru all the processing, limiting, compression, equalizing and tweaking at the transmitter), I have found that it is almost impossible to tell what spots were send to our station via CD, DAT, DGS, or MP3. And all four of ‘em beat the hell out of getting a dub on 1/4 inch, .5 mil, 7.5 ips reel-to-reel tape any day.

I think MPEG technology will soon become as common as carts. And with Digidesign incorporating an option to bounce to MP3 in their Pro Tools version 5.0, it’s bound to grow even more. To playback and encode MP3 files, we use a program called SOUNDJAM MP, which is fantastic for Macintosh. It has both a player and encoder, all in one, and was only about $50.

After encountering many problems last year, an MP3 network was set up where all the radio stations, except for a couple, in our province (state) were transferring commercials via MP3 instead of DGS. Most stations set up a separate e-mail box to receive ONLY spots. It works very well, except the popularity of it has grown so much that that e-mail box now gets VERY FULL from all the commercials sent to us. There was also a problem with confirmation. (Did you guys get the spot? Did you guys send the spot yet?)

Those were really the only problems we encountered. There have been no complaints about the quality, and you can’t beat the speed. Before, we would have to wait for a commercial to be sent to us either 1 hour, 4 hour or overnight (if it even came at all), and now we get it almost an instant after the sending station sends it. And here is the best part, IT IS FREE!!!

As for the companies that are starting up to deliver spots via MP3, I prefer slingspot.com. I have found it to be the most user-friendly, by far. It is easy to understand and uses both MP3 and mp2. It is also the only one I have found with the collect send feature. I also like the fact that any spots that are running on the station remain in your inbox until that spot’s rundate expires, then the spot is sent to their archives. Each station has its own inbox. You sign in, and if you have anything to download, it lets you know.

My only worry is that producers are going to have to check many different sources to get our spots. The last thing we need is 13 different websites, 8 ftp addresses, an e-mail box, DGS/DCI, and some spots will still come on CD (or God forbid reel-to-reel) from a traditional courier.

SlingSpotJeff Berlin [jberlin[at]kissfm.com], Kiss 108, Boston: After buying DCI, I was afraid DGS would have a monopoly on electronic commercial delivery; so I’m all for Internet based delivery systems. All I want is to be able to retrieve our client’s commercials and get them in the air studio as quickly and easily as possible, and right now DGS does the job well. When we get Prophet System terminals in all our studios, transfers from MP3 to the air studio should become seamless. Apparently, the NextGen version of the Prophet can juggle MP3, wav, and aiff file formats. As far as degradation goes, I don’t think it’s a problem if the MP3 doesn’t get converted to another file format. Our chief plans to store all commercials in the MP3 file format anyway. Degradation WILL be a problem if the MP3 has to be bounced up for editing in Pro Tools, then bounced back down into MP3 again; almost as bad as when we played a commercial from cart onto reel for editing, then back to cart!

SpotTaxi-LogoRyan Stockert [rstockert[at]yahoo. com], CISN/CHQT: Here at CISN, we use the Internet and MP3 to our full advantage. All the stations around Alberta are on-line which makes it very easy to transfer spots back and forth across the province at the best price....free! We send and receive commercials daily through e-mail and nobody’s ever complained about the sound quality. As for all the Internet company’s starting up, they offer a lot of handy features such as storage of spots for a year and instant notification upon arrival. The only problem is the 300 different passwords and user names the entire production staff has to remember. I find it a lot more convenient to click open my mailbox and have everything waiting right there.

I’ve worked at a few stations where MP3 somehow turned into a four-letter word. We’d stick with the traditional methods of sending and receiving spots (couriers, DCI, etc.) because the engineers said the MP3 sound quality sucked. These were the same stations that had clients come in with a fourth generation jingle cassette, and we’d have to run it on the air because “they pay our salary.” I don’t think the average listener hears any difference in the sound quality of MP3s on air. Besides, if the commercial is entertaining, they won’t leave your station until they’re bored anyway.

Tom Richards [TomRVO[at]e-mail. msn.com], Tom Richards Voiceovers: Compression is a fact of life, and MP3’s are the best thing out there today. For years, we’ve been looking for a digital way to get spots from here to there, and the day has come. Is it perfect? No. But neither is having your salesperson schlep all over town to pick up a commercial dubbed to 1/4-inch audio tape, either. Creepy digital artifacts versus tape hiss? Not a great choice, but I’ll take the artifacts, thanks. Let the chipheads figure out a way to make it better; that’s their job. Our job is to produce the audio and get it on the air, and MP3’s help us far more than they hurt us.

Jack Steele [jacks[at]amfm.com], AM/FM Birmingham: I just changed jobs and companies and markets going from a smaller market cluster to a larger market cluster. Ironically, the smaller market cluster had an MPEG3 PC that was a stand-alone just for this purpose, receiving only at this point. The new company is not sure or is not ready to put a separate stand-alone PC in the production room for MPEG purposes. We are receiving more and more audio via Internet. My previous Chief Engineer explained it to me that MP2 rather than MP3 was the way to go. His thoughts were that MP2 was less “grainy” sounding on the air than MP3. I listened in the control room and in the car to the stations using the MP3 stuff, and the only thing I could hear was in the control room—you might get a little distortion on the top end. Of course, this all depends if your station’s processing is set right. I found that the Windows Media Player is not as good as the downloadable WinAmp player. It had level and EQ capabilities. I think there are a lot of people on the side of MP3 because it’s the hot thing, and not so many on the MP2 side because only engineers and audiophiles are into it.

Eric Bohlen [EBohlen[at]DBCKNOX .COM], Dick Broadcasting Company, Knoxville, TN: Here at Dick Broadcasting Company in Knoxville (soon to be Citadel Communications), we are currently using MP3 and e-mail to send and receive commercials. All of the other major radio groups in town are capable of receiving MP3 files, and the only significant production house in town began sending out MP3 files about 4 months ago. We also send MP3 files to radio stations in nearby towns like Johnson City and Chattanooga, and receive from a few (not many) outside agencies and production houses. We haven’t yet begun to utilize any of the Internet companies like SpotTaxi or SpotTraffic.

As far as the quality is concerned, I have not noticed any significant drop in quality either in the MP3 files we air on our stations or the ones from us that run on other stations in town. Our chief engineer is very much opposed to MP3 files and believes that the quality difference is significant. I just don’t hear it myself, and because of the convenience, will continue to utilize MP3 and e-mail technology for the delivery and receipt of commercials.

I have even discussed the possibility of creating a web site for Knoxville radio stations to utilize where we could “post” our commercial MP3 files and have the others “retrieve” them, as opposed to e-mailing them directly to each station. I understand that many stations are already doing this in other markets.

John Peace [John[at]aperadiotv.com], Audio Production Experts: We have been sending audio to client stations via the Internet as MP3 files since 1996. We’re in large, medium, and small markets. We have yet received any complaints from Engineers or PD’s that have experienced any problems whatsoever with the audio quality.

Jay Rose [jcrose[at]tiac.net], The Digital Playroom, author, “Producing Great Sound” (http://www.dplay.com/book): MPEG—particularly garden-variety MP3—has gotten a bum rap. This is probably because there’s so much badly-encoded material on the Internet, but it’s also because of audio professionals who don’t use it properly.

At medium-high bitrates like 128 kpbs, it’s exactly as good as a stereo Zephyr connection. That’s because Zephyr and MP3 use the same algorithm. At higher bitrates—256 or 320 kbps in a good encoder—it can be absolutely transparent to even critical listeners, unless they’ve got excellent loudspeakers and have been trained to recognize the processing.

Often, people don’t get these results because they’re trying to get by with a freeware encoder instead of using a good commercial application, and choosing a low bitrate to save transmission time. But they also hobble the algorithm by not learning how to use it properly. Loading the mix with very high frequencies may sound great in the studio, but it forces the encoder to spend bits there instead of in the critical midrange. (This is particularly wasteful when you consider the bandwidth of FM stereo.) Multi-band processing, or worse, the processing-into-clipping that’s infested so much pop music, further stresses the algorithm by removing important level information. Even the choice of stereo modes will make a difference in audible distortion.

A properly-encoded sound will have enough meat left in it to survive additional encoding cycles. But bad encoding, like bad mixing or processing, just keeps getting worse.

Timothy Miles [timmym[at]mvp.net]: This is from our Chief Engineer of the Zimmer Radio Group, Dave Obergoenner <daveo[at]mvp.net>:

Tim, I’d HIGHLY recommend to the group that compression of files down to 128k (about a 12 to 1 reduction) or less be avoided. At 12 to 1 you are throwing away a lot of the audio!!! MPEG compression can sound pretty decent if it’s limited to 192 or 256k rates. A lot depends on how clean the spot was to begin with, and how “busy” the spot is in the upper mid-range. A highly compressed (meaning audio compression in this case) spot, with a lot of energy in the 3 to 8khz region will be harder to compress (data compression) without it losing a lot of quality. One other secret to having the compression come out sounding OK is to watch your levels. MPEG compression really hates clipping!!!

Our (Scott) system uses 4 to 1 APT-X compression that is fairly transparent. It works on a totally different principle than MPEG. You can APT-X compress an MPEG compressed spot without too much additional degrading of the quality as long as the spot was pretty clean to begin with, and the MPEG file wasn’t compressed to less than 128k.

Some stations use several other compression stages in their storage and transmission chains (we do not). The cumulative effect of all these layers of compression can make for some pretty ugly sounding spots or promos. BTW, SAW doesn’t use any compression.

InterServer Web Hosting and VPS


  • The R.A.P. Cassette - November 1994

    Production demo from interview subject, Greg Fadick @ WIOD/WHQT Miami; plus stellar work from Rich Van Slyke/WKLS Atlanta, Bill Schultz/WYNY New...