Telos VX User manual

Multi-Studio IP Phone Interface System
USER’S MANUAL
Version 2.0.1, May, 2014

Telos VX Manual
© 2011-2012 TLS Corporation. Published by Telos Systems/TLS Corporation. All rights reserved.
Trademarks
Telos Systems, the Telos logo and VX are trademarks of TLS Corporation. All other
trademarks are the property of their respective holders.
Notice
All versions, claims of compatibility, trademarks, etc. of hardware and software products not made
by Telos mentioned in this manual or accompanying material are informational only. Telos Systems
makes no endorsement of any particular product for any purpose, nor claims any responsibility
for operation or accuracy. We reserve the right to make improvements or changes in the products
described in this manual which may affect the product specifications, or to revise the manual without
notice.
Warranty
This product is covered by a two year limited warranty, the full text of which is included in this manual.
Updates
The operation of the VX is determined largely by software. We routinely release new versions to add
features and fix bugs. Check the Telos web site for the latest. We encourage you to sign-up for the
email notification service offered on the site.
Feedback
We welcome feedback on any aspect of the Telos VX, or this manual. In the past, many good ideas
from users have made their way into software revisions or new products. Please contact us with your
comments.
Service
You must contact Telos before returning any equipment for factory service. We will need the serial
number, located on the back of the unit. Telos Systems will issue a Return Authorization number
which must be written on the exterior of your shipping container. Please do not include cables or
accessories unless specifically requested by the technical support engineer at Telos. Be sure to
adequately insure your shipment for its replacement value. Packages without proper authorization
may be refused. US customers please contact Telos technical support at [phone]. All other
customers should contact your local representative to make arrangements for service.
We support you...
By Phone / Fax:
You may reach our 24/7 Support Team anytime around the clock by calling [phone].
For billing questions or other non-emergency technical questions, call [phone] between 9:30
AM to 6:00 PM USA Eastern Time, Monday through Friday.
Our fax is [phone].
By E-Mail:
Technical support is available at [e-mail].
All other inquiries at [e-mail].
Via World Wide Web:
The Telos Web site has a variety of information which may be useful for product selection and sup-
port.
The URL is www.Telos-Systems.com
10 9 8 7 6 5 4 3 2

Telos Systems USA
Telos Systems
1241 Superior Avenue E
Cleveland, OH 44114 USA
[phone] (phone)
[phone] (fax)
[phone] (24/7 Technical Support)
[e-mail]
[e-mail]
Notices and Cautions
CAUTION:
THE INSTALLATION AND SERVICE INSTRUCTIONS IN THIS MANUAL ARE FOR USE BY QUALIFIED
PERSONNEL ONLY. TO AVOID ELECTRIC SHOCK, DO NOT PERFORM ANY SERVICING OTHER THAN
THAT CONTAINED IN THE OPERATING INSTRUCTIONS UNLESS YOU ARE QUALIFIED TO DO SO.
REFER ALL SERVICING TO QUALIFIED PERSONNEL.
WARNING:
TO REDUCE THE RISK OF ELECTRICAL SHOCK, DO NOT EXPOSE THIS PRODUCT TO RAIN OR
MOISTURE.
USA CLASS A COMPUTING DEVICE INFORMATION TO USER. WARNING:
This equipment generates, uses, and can radiate radio-frequency energy. If it is not installed and
used as directed by this manual, it may cause interference to radio communication. This equipment
complies with the limits for a Class A computing device, as specified by FCC Rules, Part 15, Subpart
J, which are designed to provide reasonable protection against such interference when this type of
equipment is operated in a commercial environment. Operation of this equipment in a residential
area is likely to cause interference. If it does, the user will be required to eliminate the interference
at the user’s expense. NOTE: Objectionable interference to TV or radio reception can occur if other
devices are connected to this device without the use of shielded interconnect cables. FCC rules
require the use of shielded cables.
CANADA WARNING:
“This digital apparatus does not exceed the Class A limits for radio noise emissions set out in the
Radio Interference Regulations of the Canadian Department of Communications.”“Le present appa-
reil numerique n’emet pas de bruits radioelectriques depassant les limites applicables aux appareils
numeriques (de Class A) prescrites dans le reglement sur le brouillage radioelectrique edicte par le
ministere des Communications du Canada.”
This symbol, wherever it appears, alerts you to the presence
of uninsulated, dangerous voltage inside the enclosure –
voltage which may be sufficient to constitute a risk of shock.
This symbol, wherever it appears, alerts you to important
operating and maintenance instructions. Read the manual.

We support you... . . . . . . . . . . . . . . . . . . . . . . . . . . . . .i
1 Welcome 1
Note from Steve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
What’s the Big idea? . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
The VX Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
The VSet Phone Controller . . . . . . . . . . . . . . . . . . . . . . . . 4
VX Producer Windows Software Application . . . . . . . . . . . . . . . . 4
Console Controllers . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3rd-Party Producer Applications . . . . . . . . . . . . . . . . . . . . . 5
The Acoustic Echo Canceller . . . . . . . . . . . . . . . . . . . . . . . . 5
2 Installation and Conguration 7
Connecting to PSTN Lines: Gateways & PBXs . . . . . . . . . . . . . . . . 7
Using VoIP to Connect to the Telco Network . . . . . . . . . . . . . . . . 8
What’s a ‘Line’? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Livewire for audio I/O . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Step-by-step . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
The Engine Network . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
The front panel OLED/knob interface . . . . . . . . . . . . . . . . . . . 9
Network Connections . . . . . . . . . . . . . . . . . . . . . . . . . . 10
More on the Network . . . . . . . . . . . . . . . . . . . . . . . . . . 10
VSet Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
System Conguration . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Selectable and Fixed Lines . . . . . . . . . . . . . . . . . . . . . . . . 12
Studios and Shows . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Conguration Web Pages. . . . . . . . . . . . . . . . . . . . . . . . . 13
Home Page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Main page - General Conguration . . . . . . . . . . . . . . . . . . . . 14
TELOS VX MANUAL | iii
Table of Contents

iv |
Default Username, Password, and IP settings . . . . . . . . . . . . . . . . 15
SIP Conguration . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Regarding The VX and SIP . . . . . . . . . . . . . . . . . . . . . . . . 16
Server Conguration. . . . . . . . . . . . . . . . . . . . . . . . . . . 18
SIP and Network Address Translation (NAT). . . . . . . . . . . . . . . . . 19
Overall Studio Conguration Page. . . . . . . . . . . . . . . . . . . . . 19
Individual Studio Conguration Pages(Part1) . . . . . . . . . . . . . . . . 20
Individual Studio Conguration Pages (Part 2) . . . . . . . . . . . . . . . 21
GPIO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Overall Show Conguration . . . . . . . . . . . . . . . . . . . . . . . . 23
Individual Show Conguration Pages . . . . . . . . . . . . . . . . . . . 23
VX in the News and Production rooms . . . . . . . . . . . . . . . . . . . 24
Using the VX to replace ‘Couplers’ . . . . . . . . . . . . . . . . . . . . . 24
Call Audio Processing page - Audio Processing and metering . . . . . . . . . 25
Assigning sounds & Tones – The Tones page . . . . . . . . . . . . . . . . 26
SIP and DTMF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Logging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Firmware updates . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Backing up and restoring Engine conguration . . . . . . . . . . . . . . . 31
Backing/restore conguration settings. . . . . . . . . . . . . . . . . . . 32
VSet Phone Conguration . . . . . . . . . . . . . . . . . . . . . . . . 32
3 Operation 33
VSet Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Select Studio and Show . . . . . . . . . . . . . . . . . . . . . . . . . 33
Set Talent or Producer Mode . . . . . . . . . . . . . . . . . . . . . . . 34
The Line Info Display. . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Next indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Fader number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Line name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Caller ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Action ‘hint’. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Line Status Icons . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Line Button Columns. . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Hold Button. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Drop button. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Lock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Next Button and Function . . . . . . . . . . . . . . . . . . . . . . . . 37
Block All . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Numeric Keypad. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Re-dial Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Fader Assign . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Firmware Upgrades . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Take it Easy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Operation with the Element Console . . . . . . . . . . . . . . . . . . . . 39
4 The VX Producer Application 41
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Set-up: Studio and Show . . . . . . . . . . . . . . . . . . . . . . . . . 43
Managing Calls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Handset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
On-air . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
The Line Info Field . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Drop, Hold, and Hold Ready Buttons . . . . . . . . . . . . . . . . . . . . 44
Selectable Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Lock/Unlock Button and Function . . . . . . . . . . . . . . . . . . . . . 45
Fader Assign Buttons . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Next Button and Function . . . . . . . . . . . . . . . . . . . . . . . . 46
Block All . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Fixed Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Recording, Editing, and Playing Calls . . . . . . . . . . . . . . . . . . . 46
Playing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
TELOS VX MANUAL | v

vi |
Editing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Host/Producer Text Chatting . . . . . . . . . . . . . . . . . . . . . . . 48
5 Notes, Resources, Additional Information 49
The Acoustic Echo Canceller . . . . . . . . . . . . . . . . . . . . . . . . 49
Telco Services and Interfaces . . . . . . . . . . . . . . . . . . . . . . . 51
VoIP: SIP Trunking . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
IP Centrex and Hosted PBX Services . . . . . . . . . . . . . . . . . . . . 52
Number portability in the US and Canada . . . . . . . . . . . . . . . . . 52
Circuit-Switched Interfaces . . . . . . . . . . . . . . . . . . . . . . . . 52
FXS/FXO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
E&M Trunks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
T1/E1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
ISDN PRI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
ISDN BRI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
SIP Compatibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Axia Element Console as VX Controller . . . . . . . . . . . . . . . . . . . 54
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Conguring the Element to Control the VX . . . . . . . . . . . . . . . . . 56
What’s next? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Beyond Edison’s Legacy . . . . . . . . . . . . . . . . . . . . . . . . . 61
Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Audio Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Controllers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
VX Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
IP/Ethernet Connections . . . . . . . . . . . . . . . . . . . . . . . . . 63
Processing Functions. . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Studio Audio Connections . . . . . . . . . . . . . . . . . . . . . . . . 64
Telco Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

TELOS VX MANUAL | vii
Internet Speed tests . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Internet VOIP Jitter Test . . . . . . . . . . . . . . . . . . . . . . . . . 64
Packet “snier” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
VoIP Soft phone” SIP PC clients . . . . . . . . . . . . . . . . . . . . . . 65
Open Source PBX Distributions . . . . . . . . . . . . . . . . . . . . . . 65
Commercial PBX Products . . . . . . . . . . . . . . . . . . . . . . . . 65
Gateway products and suppliers . . . . . . . . . . . . . . . . . . . . . 65
VoIP/SIP equipment suppliers . . . . . . . . . . . . . . . . . . . . . . 65
Telephony Discussion and VoIP news sites . . . . . . . . . . . . . . . . . 66
SIP Information and suggested reading . . . . . . . . . . . . . . . . . . 66
Books . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
SIP Providers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Local Number Portability in the USA and Canada . . . . . . . . . . . . . . 68
Introduction to SIP’s insides for the Curious. . . . . . . . . . . . . . . . . 68
The Parts of a SIP System. . . . . . . . . . . . . . . . . . . . . . . . . 69
Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
How SIP Works . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
The State of SIP, and its Future . . . . . . . . . . . . . . . . . . . . . . 74
IAX as a SIP Alternative . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Using VX with the Asterisk PBX . . . . . . . . . . . . . . . . . . . . . . 74
Asterisk software: Distributions . . . . . . . . . . . . . . . . . . . . . . 75
Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Expansion Cards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
1 Get your ‘distro’ . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
2 Get loaded: Install Asterisk . . . . . . . . . . . . . . . . . . . . . . . 78
Log in to the Console for the rst time . . . . . . . . . . . . . . . . . . . 80
3 Conrgure Asterisk. . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Trunks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Outbound Calls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Connect your VX to Asterisk . . . . . . . . . . . . . . . . . . . . . . . . 89

viii |
Make a test call on your VSet . . . . . . . . . . . . . . . . . . . . . . . 90
VX Tech Cheat sheet – Default IP numbers, passwords, etc. . . . . . . . . . 90
Default Passwords . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Default IP Addresses . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
SIP Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
TCP/IP Ports and protocols used by the VX System . . . . . . . . . . . . . . 91
VSet telephone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Default username and password . . . . . . . . . . . . . . . . . . . . . 91
TCP/IP Ports and protocols used by the VSet Telephone . . . . . . . . . . . 91
Power Over Ethernet (PoE) . . . . . . . . . . . . . . . . . . . . . . . . 91
VX FAQ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Application Example - WKSU . . . . . . . . . . . . . . . . . . . . . . . 97
A1 Warranty 101

| 1
1 Welcome
133 years ago this past summer, a tinkerer from
Ohio scratched a kid’s rhyme into tin foil wrapped
around a cylinder. Despite the less than hit-grade
content , the warbly tone, and the lack of bass
response, Tom Edison’s demonstrations astounded
guests and founded the audio entertainment
industry. Only a year before, a gentleman aptly
named Bell had been the first boss to interrupt an
employee with a telephone call, birthing speech
communication by wire. Until the 1980s, sound
reproducers continued to work pretty much the way
Edison’s did, and telephones the way Al Bell’s did;
wiggly Grooves for the former and wiggly electrical
currents for the latter. Why did these technologies
remain in stasis for over a century, before eventually
entering a wildly innovative phase only a couple
of decades ago? The answer is to be found in
Moore’s law, which predicted a half-century ago that
silicon processing power would double every year.
Modified to 18 months, it has been on course since,
and is expected to continue to for at least a few
decades into the future. Think of all the ways this
has touched both your professional and work lives.
Digital audio workstations, automation systems, and
mobile phones are all beneficiaries of this remark-
able progress. The Internet, too, since processing
chips are at the heart of network routers, switches,
servers, PCs and smartphones. (Notwithstanding
The Great Moore’s Law Compensator in desktop
PCs, which suggests that bloat in PC applications
has taken much of what Moore’s Law has given.
Fortunately, we can avoid this in our “embedded”
designs.) So why are we still mostly using telephone
technology scarcely different from Bell’s ancient
prototypes. A nodding acquaintance with history
shows this often to be the case. A technology is
good enough – and good enough suffices. Traditions
grow roots, and the incremental improvement
offered by an innovation is not sufficiently enticing
to displace people from their comfort zones.
But eventually, the capability of a new technology
– or constellation of technologies – reaches beyond
incremental, enabling a fundamental re-thinking
of possibilities. Then POW!, that’s when the world
changes. That is just what is happening now.
Robert Lucky of Bell Labs observed a couple of
decades ago that this ever-increasing power of
digital processing was going to affect communica-
tion more than computation – and that there was
a much stronger driver for change in the former.
The Internet and smartphones have proven him
resoundingly correct.
Such is the situation exactly now with regard to on-
air phones. We now have the tools to achieve what
was only imagination until recently. As you might
know, I’ve been doing this stuff for a long time, so it
is particularly satisfying to see it all coming together.
With the VX, we’ve wedded the capability of modern
networking to the remarkable power of today’s
digital processing to bring the benefits of the result-
ing synergy to broadcast facilities.
As you discover what the VX can do, I trust you will
appreciate how it can enhance the appeal of your
listener interaction segments. It does everything
older systems did smoother, easier, better, and at
lower cost. But it also paves the way for a richer,
more natural connection with your listeners as the IP
platform becomes the basis for tomorrow’s creative
applications. It will be interesting to see what comes
next.
Warm regards,
Steve Church, Founder, April, 2011
Note from Steve

2 | Section 1
What’s the Big idea?
Is it not a bit strange that many computer-laden, all-digital broadcast studios con-
nect to the PSTN (Public Switched Telephone Network) using technology invented
in the day of phones with hand-cranks and bulbous “ringers”? Where else in pro
audio do we mix two audio directions on a connection, forcing us to imperfectly
pry the two apart in our interface gear? Where else do we use blasts of 100 AC Volts
for signaling? This becomes even stranger when you consider that the core of the
telephone network is also digital, with sophisticated internal signaling systems and
independent audio paths. Surely we can do better than this ancient bell-banging and
analog audio mash-up stuff in our contemporary telephone interfaces.
That was the idea of ISDN, and it was a good one, as far as it went. The telephone
network had begun to transition to digital in the 1960s and by the 80s, the conver-
sion of the switching and internal transmission was nearly 100% complete in many
countries. The idea of domestic data communication was just getting underway.
Remember bulletin-boards and 1200 Baud modems? The inventors of ISDN rea-
soned that if they could pass the full 64kbps rate of the network to users, they’d be
thrilled with the amazing speed! And, with two channels, you could simultaneously
talk and look up recipes. YouTube had apparently not entered their imagination.
In the modern networked world, The Telos VX gets with the program. It is the next
generation multi-studio phone system from Telos, providing a powerful, simple, and
cost-effective way to share phone lines across a number of studios using standard
IP technology. It offers a number of advanced features to enhance production of talk
shows and active DJ use of phones.
For years, you have been asking for an uncomplicated way to share phone lines
around a facility to multiple studios. And we are always hearing that you need a
way to better integrate the studio system with your office phone PBX. Finally, the
VoIP-based Telos VX lets us do this.
We’re the studio phones company. We’re also the IP-Audio company. With the
introduction of the Telos VX, we are marrying the two, creating an exciting new
approach to broadcast studio phones.
The Telos VX is a scalable system that provides a solution for stations with modest
needs, while being able to grow to support facilities that have large numbers of
Telco lines and studios.
The standards-based SIP/IP interface makes all the things we’ve wanted to do
possible. Passing calls between your office PBX and on-air system is easily
accomplished. Sharing Telco service to both the business offices and studios?
Sharing lines among studios?
Check, and check. A pure digital connection to the Telco keeps audio clean and
maintains isolated send and recieve signal paths. In studios with an AoIP audio
infrastructure, an IP-based telephone system is icing on the cake. Dozens of inputs
and outputs are connected with a single RJ-45. And you profit in other ways:
♦A single on-air phone system server can supply all the studios in your facility
with rich telephone capability.
♦A common wiring and Ethernet switch infrastructure serves both your studio
audio and telecom needs.

WELCOME | 3
♦On-air VSet controllers have rich capability owing to their connection over IP.
♦Screening software running on PCs connect over the same network, and can
include integrated softphones, thus smoothing operations and saving the
money that would otherwise have to be spent on hardware phones.
♦Mixing console control surfaces can incorporate phone system controllers
that need no additional connection; their signaling just rides on the network
connection already there. Rich status information can be displayed either on
the phone control module or the console’s main screen.
♦Recording and playback of DJ + telephone conversations are simplified. PC-
based editors send and receive audio directly over the network using their native
Ethernet connections.
♦Receiving Telco service via IP may be much less expensive than the
traditional ways.
The diagram shows a typical installation, hinting at the possibilities inherent
in the system.
The VX Engine
A 2U rack-mount device with enormous processing power, the VX Engine provides
all the call control and audio processing needed for the system. It supports dozens
of telephone lines and many studios. Its two gigabit Ethernet ports provides a cost-
effective interface to both telephone lines and studio audio via Livewire AoIP.

4 | Section 1
Call processing is sophisticated and flexible. Lines may be readily shared among
studios. A web interface allows easy assignment of lines to “shows”, which can
then be selected by users on the studio controllers. Each studio can provide its own
Program-on-Hold.
Audio processing features also have taken a leap forward. There is a hybrid per line,
allowing multiple calls to be conferenced and aired simultaneously with excel-
lent quality. Each line is also equipped with AGC, automatic EQ processing, and
override ducking.
All connections to the Engine are via two Ethernet jacks that are extended with an
Ethernet switch to support a wide variety of peripherals: telephone lines, Livewire studio
audio, VSet phones, VX Producer PC applications, console-integrated controllers, etc.
The VSet Phone Controller
While you can control the VX with PC applications and mixing consoles. Most
systems will include one or more Telos VSets. These are the phone-like controllers
that have handsets for off-air conversations.
IP-based Telos VSet phones have large, high-contrast color LCD panels that provide
line status, and caller information. Caller description text that is entered into compat-
ible call screening applications will show up on the LCD near the line select buttons.
For the comfort of familiarity, the VX can work like a traditional Telos controller, with
calls being selected, held, and dropped in the way to which operators have grown
accustomed.
But because the VX system has a hybrid per line, it is often desirable to spread
multiple calls over a number of faders, using one for each call so that operators
can control each line’s level individually. The VSet offers this possibility. It is also
possible to hard-assign individual lines to fixed faders, such as for VIP calls.
VX Producer Windows Software Application
The VX Producer application takes studio phone operations to a higher plane. It
provides the usual call screening functions for phone-active broadcasts – but with
a number of enhancements enabled by the IP nature of the system. The integrated
softphone uncomplicates the producer’s life, since the PC interface is used for all
operations, including answering and making calls, assigning priority, writing notes,
etc. It also reduces cost, as no hardware phone need be installed.
It has a built-in audio recorder/editor. A producer can record and edit a phone call
without leaving the application. The resulting audio files can be easily sent to the
talent PC for quick and convenient airing. We imagine that this simple, but powerful
feature could add an interesting new element to many call-in situations. Callers who
don’t have time to “wait their turn” could be quickly recorded and carefully edited.
Perhaps montages could be created to open segments. Removing the need to wait
might encourage comments from higher-quality callers.
Because Livewire audio is available at the PC via standard LW Driver software, a
producer can readily record calls for later play. These could be edited with a PC
application running on the same machine. When a file has been produced, it can be
sent to the on-air studio over the network.

WELCOME | 5
Thus, the one Ethernet cable is used for:
♦Telephone audio for the softphone, via Livewire.
♦Livewire audio for the recording of calls.
♦Transfer of recorded call files from the producer to the studio.
♦Data messages between the PC and the VX main box for line selection, etc.
♦Data messages such as call notes and IM between the producer and on-air
studio.
♦Possibly, database lookup of caller information, such as how many times
they have called, the quality of their contribution, whether they have won any
contests, etc.
♦Web browsing, email, etc.
This is the power of IP realized. To accomplish this level of functionality with older technolo-
gies would have been impractical.
Console Controllers
Integrating phone line selectors into the studio mixing console is an operator-
pleasing feature that is easy to accomplish in a networked studio. As this is written
in March 2011, the following consoles have VX-compatible call control modules
available.
♦Axia Element Console
♦Axia IQ Console
3rd-Party Producer Applications
The VX uses an open protocol for control, which permits non-Telos software applica-
tions to be used in place of, or to augment, the Telos VX Producer application.
Broadcast Bionics and NeoSoft offer such applications.
The VX system components are linked via a standard Ethernet switch. In Livewire-
enabled studios, this will already be present and no additional switch would be
needed. Facilities that already have a VoIP PBX would also probably have a suitable
switch in place.
The Acoustic Echo Canceller
A new acoustic echo canceller algorithm solves the longstanding problem of
feedback and echo when a loudspeaker-to-microphone acoustic path is required in
the studio, such as when DJs prefer to record calls without using headphones or
when guests need to hear calls without headphones. The AEC in the Telos VX is a
remarkable new development. Its performance is shockingly impressive, permitting
very high loudspeaker volume with no noticeable feedback or return echo. (If you’ve
already experienced the Axia intercom system, you know what we’re talking about…)

| 7
2 Installation and Conguration
The diagram shows a generic installation that could be used in a typical studio. Two Ethernet
switches are employed to keep the isolation between the WAN and LAN ports on the VX
Engine. The LAN port carries the Livewire audio and everything else but the VoIP, which is on
the WAN port. Telco lines enter two ways: From the PSTN via a gateway and from a SIP VoIP
provider over an IP network. VX Interfaces provide analog, AES, and/or GPIO connections to
traditional studio equipment. They could be thought of as another kind of ‘gateway’. And just as
with the Telco gateway, they are not needed when the studio equipment can accept AoIP natively.
For an example of this sort of installation, see Axia Element Console as VX Controller in Section 5.
Connecting to PSTN Lines: Gateways & PBXs.
‘PSTN’ is an acronym for ‘Public Switched Telephone Network’, the traditional telephone
network that includes POTS, ISDN, and T1 as ‘last-mile’ connection technologies.
The VX system connects to Telco lines using industry standard SIP (Session Initiation Protocol).
This means it is compatible with a wide variety of VoIP services, gateways, and PBXs. Gate-
ways are used to interface PSTN lines to SIP. This is how analog POTS and ISDN lines connect
to the VX. Gateways are off-the-shelf for POTS, T1/E1, and both BRI and PRI ISDN. These can
be rack-mount units that support large numbers of connections or low-cost desktop boxes that
interface a few POTS lines.

8 | Section 2
The “gateway” could also be a full-up IP PBX, such as from Cisco, Digium (Asterisk), and many
others. In this case, compatible VoIP phones can be used for general office locations. SIP lets
you move calls between the office and studio systems with no audio degradation. A PBX such
as Asterisk could add additional capability, such as automated attendant functionality. With
appropriate cards, Asterisk makes an excellent gateway to T1 and ISDN PRI Telco lines.
Using VoIP to Connect to the Telco Network
Recognizing the growth in market share of VoIP PBXs, Telcos are beginning to offer “SIP Trunk-
ing” service, which delivers phone network connectivity directly over a controlled IP link. With
this service, you wouldn’t need a gateway.
While it remains a niche in early 2011, SIP trunking is growing in support from both PBX
vendors and carriers. Over time, this will almost certainly reduce the use of the older POTS and
T1 trunking. Eventually, it may replace it completely. See the Resources section for a list of SIP
VoIP providers that we’ve tested with.
What’s a ‘Line’?
While we are talking about Telco lines and VoIP services, we should take a moment to consider
– just what is a ‘line’ these days? Use of the word ‘line’ is becoming bothersome at this point in
telecom history. Back when an analog line was associated with a single telephone number, the
word had a clear meaning. When you ordered ten lines, you received ten physical wire pairs
and had ten telephone numbers. (Yes, “roll-over” rotary service exposed only one number to
the public, but the others were still there.) ISDN was the first step on the path to trouble. We
engineers began to speak of a BRI “line” with two “voice channels”. But producers and hosts
still communicated with each other as if channels were lines, saying things like, “The tree-
hugger is on line 3. Do you want to take him now?” We knew that meant BRI line 2, channel 1,
or T1 channel 8, but users had no clue.
ISDN PRI made matters yet more knotty, since the telephone number and physical channel
were divorced. Now we are faced with SIP trunking and other IP-based services, where a single
link (which might be connected via one, two, or more physical copper pairs, or an optical cable,
or via a wireless system) might carry any number of voice channels. (And what is going to
happen when phone numbers become obsolete, as they already are for VoIP applications such
as Skype?)
Users, blissfully unaware of all this, will undoubtedly continue with their conditioned habit,
referring to a certain caller as being on a particular line. Thus is the word ‘line’ destined to join
‘dial’ in a peculiar departure from original meaning.
In this manual, we refer to “lines’ as your users would. Usually that means a particular tele-
phone number that is probably associated with a button on the VSet phone and/or console
controller. To keep the ambiguity down, we’ll try to remember to call the physical links “con-
nections” or “interfaces”. And we’ll sometimes refer to ‘calls’ when the sense points more to
the conversation than the connection.
Grandstream GXW4004 4-port FXO gateway

INSTALLATION AND CONFIGURATION | 9
Livewire for audio I/O
The VX uses Livewire for all audio I/O. For studios that are already Livewire-based, this ap-
proach saves money and simplifies installation. With its simple support of bi-directional audio
flow, Livewire is ready for hassle-free mix-minus.
When needed, traditional audio connections are provided via VX Interfaces, with Axia Livewire
connectivity. These come in both analog and AES3 versions. Because they are networked,
they can be located where convenient, either in individual studios or in a central rack room.
Each standard Interface connects eight stereo audio inputs and eight outputs. The many
audio converters and connectors that would be needed to interface the multiple hybrids and
program-on-hold inputs are reduced to a single Ethernet RJ-45.
Livewire is both an elegant technical solution and an unprecedented value. Only one Ethernet
RJ-45 connects dozens of bi-directional audio channels and rich control.
Step-by-step
There is a lot of information in the pages that follow. Here’s the (very) abridged version of what
you need to do to get your VX system up and running.
1. If you will not be using an existing network to support the VX, install the Ethernet switch,
or switches, depending upon your needs.
2. Mount the Engine and set the IP address or accept the default. Make the network connections.
3. Install and configure your gateways if you will be using them to interface to POTS, ISDN,
or T1 PSTN lines. If you will be using VoIP trunking for your Telco connection, get it
connected and gather the IP and registration password info.
4. Get a web browser going and do the system configuration.
5. Move on to install and configure the VXset phones and VX Producer software applica-
tion. Then to any other controllers you have in your system, such as integrated console
controller modules.
The Engine and Network
The front panel OLED/knob interface.

10 | Section 2
The Engine front panel display gives at-a-glance status information. The main screen is
pictured above. It shows the IP number for the LAN (Livewire) port, its connection speed and
status. The overall status and CPU temperature are also indicated. The knob lets you scroll
through the menu pages.
Among the menus is one that lets you change the IP address and another that shows the status
of the Livewire audio channels.
The main screen, shown at power-up, is pictured above. To see any of the other pages /menus,
push, and then rotate the knob to show each in turn. Pushing the knob enters you into the
menu that is displayed. Editing items inside menus, such as the IP address, is similar - navigate
to the specific item you want to change by rotating the knob, then push it to choose the item,
such as the IP address. In the case of the IP address, select from among the digits by rotating
the knob, then pushing. Finally, rotate and push to enter the value you want. (yeah, this isn’t
the most convenient of user interfaces, but you shouldn’t have to use it; the web interface,
once available, is much more friendly. The reason for the IP address entry here on the front
panel is to avoid the circularity that you need the IP address to connect a web browser, in order
to enter the IP address. (should the default not work, for some reason.) We think you’ll also
find it convenient at times to have the IP address displayed on the front panel.
Network Connections
The VX Engine has two RJ-45 Ethernet jacks on the rear panel. Both are 100/1000 auto-speed
setting. The upper (LAN) port is for Livewire audio and, by default, everything else, such as PCs
used for web-based configuration, VSet phone controllers, producer PCs, and console control-
lers. This can be connected to an existing Livewire network or to a new, dedicated, network that
you create to serve only the VX system, which could be as simple as a single Ethernet switch.
For audio to work, there must be at least one Livewire device capable of supplying clocking
on the Livewire network. Normally, this would be a Livewire audio Node. The Axia Element
console Powerstation can supply this clock.
More on the Network
An appeal of the Ethernet/IP approach to building studios is that you can make them as simple
or elaborate as your needs require. The components of a VX system: the Engine, VSet phones,
console controllers, and PCs are networked together using standard, off-the-shelf Ethernet
switches. A small VX system might have only a single Ethernet switch as the ‘”network infra-
structure”, while a large full-facility setup could have dozens of switches and an IP router or two.
The Ethernet switch on the Engine’s LAN port must be Livewire capable. That is, it needs to
support multicast. Switches that are not multicast-capable usually flood multicast traffic such
as Livewire audio streams to all ports, potentially overwhelming devices like PCs and printers
- So you don’t want to plug the VX LAN port into an office network after Livewire outputs are
enabled! ! Multicast-capable switches will not propagate the Livewire traffic to ports that are
not subscribed to a particular audio channel. Thus blocking the high-volume traffic from places
it is not wanted. A suitable switch would be the Cisco 2960G or another from that family. The
switch that is part of the Axia Element PowerStation is also suitable. Of course; the VX and
Axia consoles were designed to work smoothly together.
For the initial, out-of-the-box, configuration, the foregoing is not a concern. You can safely use
a simple Ethernet switch or an existing LAN to get your configuration PC to the VX LAN port