IP audio network audio what does that mean and is it any different to
100 volt line to low impedance? Where does it fit in?
So to start with audio-over-ip some type of network device, you have to
start with a raw audio signal, it comes in the same way into a microphone.
Now depending on what manufacturer what brand of microphone,
it can get converted there into a different type of signal. A digital
signal that we can take and put on the network
or it might go into a traditional microphone that goes into a
digital signal processor and that would change it into
packets or some other type of protocol that we could send over
existing infrastructure. And once it's in packets we can pretty much send it
where we want, we can do with it as we wish. There are
loudspeakers now that have powered amplifiers that
receive these packets and re-encode them into
audio and reproduce it. Or it can go to another DSP that will de-encode it and
or re-encode it and reproduce it like a traditional system.
So why do we want to do this? What's the difference? What's wrong with
current distributed sound via 100 volt 70 volt line? What's wrong with low
impedance? Well the the limitations of low
impedance and traditional audio is that usually it has to stay within the
room or within the building. Once we exit a building and want to go
downtown or to another city or across country or across
the world - we really can't do that with a
traditional audio system. Even very large audio systems like the
telephone system have limitations. We can get cross-country but
the fidelity is not quite there. With networked audio once we change it
into packets, we can send it anywhere in the world.
It's an ethernet packet at that point in time and it can go anywhere email can go.
So i can send my audio system from this room
for a large all hands meeting for a you know a
multinational company and they can receive it all over the world at the
same time. Granted there will be some latency but
it's not going to be as bad as trying to get
electrons down a speaker cable for 20 miles.
It's going to be a lot more functional for very large projects
and the cost of infrastructure now is going to go down because there's not as
much copper. We can send many many audio signals down one
ethernet line and it takes the place of bundles and bundles of copper.
I mean even the older protocols were doing 64 64 64 one way 64 another and if you
think about a 128 channel snake that's a huge bundle of copper replaced with one
category cable now and a couple boxes.
Now we've been talking AV IT for let's say five / ten years now and
there has always been an argument as we
migrate towards IP of installers saying 'well the IT is not going to let
me anywhere near his network'. Have things changed now?
Things have changed and I think it's because of our understanding as audio
video professionals that now we live on the network.
The convergence has happened and this is a thing we do now.
So what we're really doing is working more with the IT
and the land professionals - the land managers. They have two main jobs:
network has to be secure and it has to remain up and if they don't know what's
on their network that could jeopardize both of them.
So knowing this now and knowing more about network operations and
how the LAN actually functions and all the things associated with that.
We can better prepare as AV professionals
to work with the IT managers to make sure that we have enough bandwidth, we have
enough headroom, if we need VLANS or virtual lands
that we can set that up ahead of time. Things like we
just don't show up and say where can i plug this in
because that could be detrimental to both security and uptime.
Learning how to months ahead of time say
'what of my system do you need to put into a development
network to see - what ports we need open, to see what protocols are going to
happen? Any security restrictions?'
And as we learn to work on the network more and more
efficiently, I think we get more of that cooperation.
We all have to live on the network now it's just like driving on the roads
and it doesn't matter if you drive on the UK side or the American side.
We all have to obey the traffic laws.
So as we progress further into IT and into living on the land -
I think our understanding and how to work with
the IT professionals is just getting better and it's
developing a better relationship and it's getting easier.
So if a conventional audio or an AV installer is upskilling to add those IT skills
we still need to design an audio system, have the rules changed?
Or is designing an audio system just the same but over a different platform?
So designing an audio system, you're always going to have to deal with physics.
Room physics, acoustics just the back
end electronics are a little bit different.
We still have vibrations that have to be transduced through a microphone,
gets sent down a cable, processed and then once it's processed there's new engineering.
How much bandwidth does that take up?
How much am I going to put on the network? And I have to do calculations for this,
for how many channels - to make sure i don't saturate the network.
And then once I'm done with that, converting it back into an audio signal
into an amplifier - the physics again are the same as
traditional audio. How loud does it have to be to get above
ambient noise? How much coverage do I have? What type of fidelity do I have?
So not only do we have to know the old things, but now we have to incorporate
all of the network side - the engineering that goes into making a good clean audio
system through ones and zeros.
You talked about you know some of the benefits of audio over IP being distance of course.
But another of the major benefits is zoning as well - the level of control
available to you just increases exponentially, explain how that works.
It does - so zoning is a great thing because we have
control, the more zones you have the more control you have over your audio.
Volumes can get louder or softer per zone. We can EQ them per zone, so if we
have the same audio signal going into several different areas, we can do different things with the audio.
Like i can reduce the volume if the ceiling speaker's lower than just
having it louder in that area. The control is amazing and with ceiling
speakers nowadays being their own node, receiving their own audio channel, having
their own audio amplifier. I can have amazing amounts of control
as you know, the more control - the more management we have to have.
But I think the benefits of that putting in a little bit extra up front getting
everything just right dialed in and being able to
have that control of an individual node to give us what we want is spectacular.
It's so much easier than just doing an overall EQ or overall volume and just kind of letting it be what it
is or trying to retap loudspeakers. Another nice thing
is these loudspeakers with amplifiers built in are powered over ethernet. So I don't have to run separate power
cables to all my amplifiers. I can get a PoE switch,
give it to eight or ten loudspeakers and and that's good.
One cable - not a lot of infrastructure as long as you run our cabling correctly
and make sure it's all certified everything will work out great and not
having to go up and touch that loudspeaker, that amplifier afterwards
not having to get on a ladder and being able to do everything from a
workstation. The benefits are amazing.
Service is quicker, commissioning is quicker, getting everything tuned is a lot faster - a lot more efficient.
So I guess in a conventional analogue system a great product is what it's all about.
With an IP system when you're when you're looking for a good IP system,
it needs to be fantastic product but having a good
user interface, a good control platform - that makes the whole thing easy,
from a laptop even from your phone these days - is a big part of a good system there.
Oh yeah any UI is gonna make or break how effective the system is.
You can have a beautifully designed system and if the user interface isn't very good it's like not having a
good steering wheel on your car. No matter how well your car runs, if you
can't control it, iif you have issues with that it's going to be more
difficult and you're not going to want to drive that car.
With a good user interface in any any network system, a good user interface
is paramount and having that functionality and availability and
ease of use is all about not just the experience for the client
but the experience for the programmer or for the engineer.
That has to be there too and just like the clients enjoy
a good experience from the AV system, the AV
providers enjoy a good user interface - a good experience from
the equipment that they put in.
As audio over IP grows and grows with seeing installers who are
considering it but don't want to go out there and do a worldwide system for instance.
But it's not a case that if you've got let's say a number of disparate analogue systems,
it hasn't all got to be replaced you can actually create a hybrid system is that right?
Sure sure. If you have an existing audio system and
you wanted to make it a networked audio system say in a
traditional classroom or conference room you can add a box.
And there's many manufacturers out here who sell
many different types of boxes that will do that and do it well.
You can integrate this box to have a gozinta an input
and a gozada and a separate LAN that goes both ways. So I can have my
traditional system, add a box have an input going into
that box and output coming out of that box, input and output from
the LAN and now I can connect several classrooms or conference rooms together.
So it's not that the old traditional system is going away,
we're just adding some things to make it better, to make it more user friendly,
to get the small classroom to now be part of a larger network of classrooms
to work for overflow or campus or enterprise wide
discussions or talks and to just be a lot more functional.
Audio is always going to be analogue, but the way we treat it from
the time it leaves here to the time it gets there - that's evolving.
That's evolving for the better.
I guess what you were saying there at the same time is that the ideal solution for
every system, the scalability to consider really you
know there will always be 100 volt lines, 70 volt - maybe not always,
maybe it will take over one day. But yeah I don't think we need to try
and apply it to everything do we at the moment?
No we don't it's really going to depend on your enterprise goals and your strategic
vision of what you're going for, If you have one or two conference rooms and
they're in the same building. No it might not be worth the cost the ROI might not be there to
put in the cabling or to buy the new equipment.
But if you have a very large enterprise or a campus
that has a lot of different systems in it, a lot of different
audio and video systems. Things that maybe professors use
and you know they're professors of a certain art or certain science.
They're not audio video professionals, we don't expect them to be -
managing that might really benefit from some AV over IP.
Being able to dial in or just listen to what's going on if they say I
have some problems. Being able to listen in from a central
control room before you run out and realise hey the microphone's just too
hot I can turn it on from here and fix a problem instantly. So some
things will benefit, some things will be the same.
The traditional 100 volt 70 volt speaker lines low impedance speaker
lines they're not going away, but even at large rock concerts where we
have fly rigs and massive amounts of speakers where
there's still low impedance 8 ohm 4 ohm loudspeakers
those amplifiers are getting fed by category cable.
Those digital signal processors are you know it's one category cable instead of a large snake.
So every aspect of audio video can be affected by this. Whether it's
large rock concerts or a small classroom but the traditional system of audio
video it's going to be there for a while.
Let's just talk about compatibility just as a warning if we've got 100 volt line systems, we can pick up that brand
of speaker, that brand of amplifier, that brand of
mixer, plug them all together and they will work same with low impedance -
not actually the case with audio over IP is it?
No there are several different protocols and some of the different protocols have their own rules -
they require their own type of box. So when starting to design some type of
AV over IP or audio over IP, you really want to
make sure you're trained well on all of the aspects before you start designing
and buying boxes and trying to stick one box with the other.
You really want to make sure that everything is compatible
and protocol compatible. You can get different boxes from different
manufacturers, as long as they're protocol compatible.
If they're not protocol compatible, we're going to have a lot of paperweights
sitting there trying to get information that aren't talking to each
other. So it's it's very very important that the protocols are all compatible
with each other and again there's so many manufacturers that
make boxes that are protocol compatible, different price points, different sizes
the sky's the limit out there though. So just to round it up then audio over
IP - it's everywhere now. You will start to see it more and more.
The benefits are let's go through them again: we've got distance
transmission, we've got the fact that you can use
existing ethernet cabling that's already in the building. What else have we got
the cost I mean if you think about scalability of the cabling alone
those big giant snakes - that's a lot of copper and copper cost money
and i can replace a huge huge bundle of copper with one category cable.
It's actually reduction in cost, one of the cost analysis we do in design class
is designing a live audio system with 64
channels back and forth, the cabling infrastructure with conduit
and everything else came out to about $65,000.
When we did it over IP the cabling infrastructure conduit and everything
else came out to about $5,000.
So the cost of the actual infrastructure if you're reducing from a large scale
audio, to category cable is an incredible savings. So there's a
cost benefit, zone control of course we talked about.
Zone control and the flexibility just becomes enormous and one thing that
just popped into my head for installers is that the way that you
service the system changes out of all recognition with a
conventional analogue system. If you've got a service contract you've
got to go to site let's say once twice a year
and check that through. Every single speaker or zone on the system can now be
serviced and tested from the desk.
Oh you're right, yeah it's own node. Its own little computer
and you can run diagnostics on it, you can see if it's putting out signal or
not. It will tell you loudspeaker
impedance, it will tell you temperatures of the loudspeaker
it will give you all the information of that loudspeaker and if there's a fault
it'll tell you if there's a fault even before you go out to service it, it will
say - hey something's wrong with me I think
somebody needs to pay attention and shoot you an email.
And then that reduction in going back and forth
on a quarterly or a bi-annual visit we really don't have to do that. We can
check on the system pretty much anytime we want and only
have to go out if there's an issue and you know nowadays there's not a lot of
issues they pretty much work.