Today's OB trucks must handle dozens of signals. MADI is an efficient way to do so. Image courtesy Steve Lampen, Belden.
For contemporary cutting-edge audio infrastructure, many broadcasters continue to choose AES10 (ANSI S4.43-1991), a.k.a. MADI, to transport up to 64 channels of digital audio over a single coax or fiber optic cable.
While the original idea for MADI was catering to a very narrow recording studio application, the standard has survived to address the expansion of digital production and HD workflow for broadcasters.
A few years ago, MADI saw a resurgence at a time when newer IP-based technologies were still a glimmer in engineers’ eyes. Today, audio over IP/Ethernet is a reality with manufacturers offering several flavors such as AVB, DANTE, RAVENNA etc. So why aren’t broadcasters beating down the doors to buy Ethernet-based audio solutions for production facilities?
There are many advantages to using MADI over analog/AES, and the broadcast industry’s familiarity with it enables the standard to remain a good choice. While audio-over-IP is making great strides, there are few tools available to suit broadcasters' unique requirements.
Any MADI solution must incorporate multiple signal processes, from de-embedding audio from 3G video to routing a variety of signals to displaying important information to the user via front panel meters.
MADI is primarily used in the distribution of audio only signals within the production environment. For broadcasters it has found a particular niche in the OB truck market where weight, simplicity, and reliability are paramount. The US OB market in particular has embraced MADI mainly because of the difference in how people use “comms”. Traditionally, every position would have had an audio monitor being fed with eight channels of analog or AES. Running eight lots of analog audio to every single position through huge patch bays is very cumbersome, very heavy on the copper, and very old school these days.
When MADI was introduced, rather than using eight lots of analog cables, a single coax cable was used to carry those 64 channels, which can be daisy-chained, with eight groups of eight to the different positions. MADI I/O is now a standard feature on most of the big audio and video routers. This is now very common in the US and finding more widespread global adoption, which is why demand remains high for MADI monitoring equipment.
One of the other reasons why MADI re-gained popularity had little to do with any significant changes to the technology itself but rather with the trend towards more integration between manufacturers and technologies. Today it is quite common to integrate the intercom system with a digital audio router system. With MADI this can be easily achieved between any systems supporting this simple and effective standard.
What is the future for MADI?
Today, as technology development for IP/Ethernet solutions continues, what is the future for MADI?
Beyond pure familiarity, the live production industry is very conservative --for good reasons-- when it comes to changing technology for mission critical workflows. If we have something that serves a purpose well and is proven reliable, we’d be fools to go away from that in a hurry, just to try out a new technology with a couple of new features. There’s a lot on the line in a live event, so there’s much more at stake, and only one shot to get it right. Naturally, this leads to a more conservative mindset.
Audio-over-IP is still an unknown for a lot of people, and seen as inherently risky, in an industry that works very hard to minimize risk. Trusty old coax cable is easy to make, fairly easy to test, etc. There’s typically one interface where users can do all of their video routing, but also all of their audio routing for the entire truck. It’s not yet another piece of software they have to open to start managing streams.
“I have yet to have a request for Ethernet-based audio on the trucks that we build although the IP infrastructure is already there for other reasons,” says Ian Bowker, owner of Icon Broadcasting, a company that specializes in the design and building of OB trucks. “One of our major clients requested MADI be used on the new truck we’re currently building for them.”
The TSL SAM1 MADI solution requires only 1RU while providing sophisticated signal processing and multiple outputs.
It’s a nice flexible standard that works on very cheap cables and 64 channels is sufficient for most purposes. If you put it on fiber you can get some really long distances as well. So, while MADI will have some time to run, it will eventually be replaced. There’s no two ways about it. The next generation of trucks being built will probably stay on MADI, but maybe the year after, they’ll likely cut over to audio over IP because there are distinct advantages. But for the foreseeable future, MADI is still a solid choice!
At TSL, we are fully supportive of everything that is happening with MADI and developing new MADI products, as the demand is still high. However, as formats like audio over Ethernet, RAVENNA, Dante, etc. are gaining ground, the days of MADI will eventually come to an end. Therefore we are also actively developing products for an inevitable future when all signals will definitely be audio-over-IP.
You might also like...
We explore the basics of physical connectivity & signal management encountered in broadcast audio systems alongside the destination recording devices.
Quantum Computing is still a developmental technology but it has the potential to completely transform more or less everything we currently assume regarding what computers can and can’t do - when it hits the mainstream what will it do…
At the heart of virtually every IP infrastructure and its inherent IT network is a software layer that acts like a conductor to make sure the system is working smoothly. Some call it the orchestration layer because it instructs each…
Broadcast audio is going through a renaissance and in the battle for viewers every content provider is looking at how to increase output and improve content. While the headlines might look familiar, IBC’s audio exhibitors are responding to these n…
The reality of the adoption of IP based workflows is that most broadcasters are running hybrid infrastructure that combines SDI, IP and IP enabled cloud and there will be plenty at IBC to help smooth the hybrid transition.