Irish Eyes Smile on Telos Z/IP One
Ireland — Zenith Classic Rock is an Internet radio station of some
notoriety: It’s one of the longest-running, having been online now
for more than 10 years, and has therefore picked up a faithful
following of listeners who tune in to hear a unique blend of classic
rock standards interspersed with deep album cuts and oft-neglected
tracks from the rock genre.
they do radio in Ireland: Zenith Classic Rock jock Paul Dower toasts
the Z/IP One on St. Patrick’s Day, 2013.
the start of every year, this station gets to broadcast to the
Southeast of Ireland in the traditional sense, on AM, FM and DAB, by
means of a temporary license.
licenses are relatively easy to come by in Ireland, but duration is
limited to 30 days per year. Zenith uses these 30 days as 15 weekends
makes use of automation most of the time, but during their annual
forays into the radio frequency spectrum, they present mostly live
programs. The studios and transmission facilities are rented from my
company, Total Broadcast Consultants, so it was up to me this year to
ensure that this station sounded as good as possible on-air.
studio location is some 30 miles from the transmitter site, which is
a mountaintop equipped with a 30-meter tower, antenna system and 1 kW
previous years, the station used a UHF composite link to get its
audio from studio to transmitter, but that wasn’t possible this
year due to a change in studio location. There is now no line of
the transmitter site does have Internet access by means of a
fixed-wireless Internet service company, and the studio location has
Internet from a cable service provider. So this year, we decided to
use this medium.
installed a Telos Z/IP One codec at both ends. I knew this would be a
good test of the codec’s capabilities because a continuous program
feed over the Internet is quite a daunting prospect.
studio is Axia-based, so interfacing the Z/IP One via Livewire was a
piece of cake. At the other end, the AES/EBU digital output fed the
FM and DAB processors.
wireless Internet provider’s system has a pretty strict firewall
arrangement and initially I found that the Z/IP Ones couldn’t
manage a direct connection to each other, but the relay system Telos
has built in — a connection via one of their Z/IP servers —
worked fine while we struggled with port-forwards, NATs and various
esoteric mechanisms to get the studio to “see” the transmitter
site directly over the public Internet.
method worked fine for the first weekend’s broadcasts, and by the
second weekend, we had the codecs connecting one-to-one.
love how you “introduce” the Z/IP Ones to each other. Just give
them a unique name, and they appear in the directory shown on the
unit’s display. Select the target unit, hit “Connect” and
you’re off to the races.
a stickler for audio quality. I hate hearing the artifacts of bitrate
reduction, so would have preferred to run the link linear, i.e. with
no compression, but the bandwidth required proved too taxing for the
Internet upload capacity, so instead I opted for AAC-ELD coding, at
I couldn’t hear the difference on the received FM signal between
linear and the AAC-fed transmission. In fact, I thought the AAC
implementation by the Z/IP Ones sounded better than I had heard with
other manufacturers’ codecs — a nice clear top end, no “swirling”
and full bottom end.
FM (and Internet) audio processing is excellent, and always gets
praise when on air. This year was no different — ordinary listeners
actually did contact the station to say the quality was superb!
in terms of reliability, I did hear a few fast dropouts, but looking
at the logs in the Z/IP Ones, I could see that the upload capacity of
the Internet link had simply bottomed out. I also saw that some very
bad stuff had happened on quite a few occasions to the data
throughput, but the connection hadn’t dropped. Telos’ “Agile
Connection Technology” obviously works. The link was reliable for
the 15-weekend run of live broadcasts.
information, contact Telos Systems in Ohio at (216) 241-7225 or visit www.telos-systems.com.