PRODUCT REVIEW: Aviom® Pro64™ Digital Audio Network

In Uncategorizedby tfwm

When asked to review the new Pro64 Series™ Series™ digital audio network products from Aviom, I had to first make a distinction between a point-to-point digital snake system, and a digital audio network. Because of this, the applications for this product are almost as deep as the product itself.

The Network
Where the innovation really lies in the Pro64 Series™ products is that they possess all that we would need from a great digital audio format, but rather than trying to compete as a format alone, they have created an audio network. Unlike many digital audio formats, the Pro64 Series™ version of Aviom’s A-Net™ provides connectivity from any point to any point in the network, regardless of where individual boxes are or how they’re connected. In Auto Mode the Pro64 Series™ system allows us to send and receive 64 channels of 48k -24bit audio (16 channels at 196k -24bit audio). Manual Mode allows us to pre-designate the two available network ports A and B for specific directions while expanding the system to run up to 64 channels of 48k -24bit audio (16 channels at 196k -24bit audio) in each direction, totaling 128 channels!

The beauty of the A-Net® network is that it is NOT Ethernet. There are no switched packets. This makes the system very flexible. Not only can you plan for audio to go where you want, you can feed or receive to and from the network at any location within 400 feet of the last component, again using one Cat-5e cable. You can even change your mind as your needs evolve. As in the Pro16™ system, A-Net® only uses the physical layer of the Ethernet format, not the protocol. Whereas Pro16™ uses one of the four twisted pair wires within Cat-5 for 16 channels, Pro64 Series™ uses two of the available twisted pairs. This means that, much like with the Pro16™, with the proper wiring scenario, we will be theoretically able to use the other pairs to increase channels into two streams within the same Cat-5 cable.

Not having traditional packets greatly improves performance as well. Where latency is usually an issue, this system has only 800µs of latency from analog to analog source- basically a non-issue. Latency is not only important because of accumulative, audible delay, but phase as well. Where phase shifts, so does frequency cancellation and stereo field degradation based on the amount of delay. The ultimate gift, is there is no compression in the audio stream!

In addition to audio, the system has 14 Virtual Data Cables™ (VDC™) that allow the bi-directional transport of MIDI, RS-232, RS-422, and GPIO. I like this feature a lot since I use MIDI triggers for our band leader to trigger show control events and songs from a keyboard.

What is vastly important is that they are supporting the entire Pro16™ line, including the A-16II Personal Mixers that many of us use by way of the ASI A-Net® Systems Interface module that breaks out banks (or “Slot ranges” in Pro64 Series™ terminology) of 16 channels.

The 16-channel 6416i Input Module employs selectable sample rates ranging from 44.1 to 192k, all at 24bit. While the number of available channels on the network scales according to the sample rate selected, you still get 16 channels of input whether the sample rate is at 44.1 or 192kHz. Users have the ability to assign any one input module the function of being the “Control Master” which includes setting master clock, sample rate, mode of operation, as well as error reporting, passwords, etc.

The network has a 64-Slot capacity at 48kHz, allowing many input modules to coexist in a network. The user can activate channels on input modules as needed, making the network extremely flexible. The Slot Range numeric readout is easy to see for a quick reference as it numerically displays the first number of each 16 channel Slot Range; 1, 17, 33, etc. Fortunately, it doesn’t occupy all of the 16 channels in the network. Each of the 16 can be activated individually or in adjacent even-odd pairs by simply pressing the LED enhanced activation buttons on the front panel. They indicate an active and inactive connection, or that the specified channel is already in use by another input device set to the same Slot Range in the system.

The 16-channel 6416o Output Module looks and functions very much like the input module but is designed to access any channel on the network from any input module using the same Slot Range of 16 channels. All you do is press the channel buttons to activate the signal on that channel of the network.

The outputs can be used at mic or line levels. In addition to XLR outputs, there are two DB25 alternative output connectors. You can theoretically assign as many output modules as you want to the same channels, perfect for multi-splitting to any location at any time. The one thing I expected to see in both the input and output modules was the ability to access multiple Slot ranges from within the same box. This is not possible. Each input and output box is hardware-dedicated to the 16-channel group that is selected on the front panel. This just means you may need additional boxes in some layouts, no matter how few channels you need to feed or access from the specific Slot Range (see PPT slide 39). But again, it’s as easy as plugging in the box, selecting the Slot Range, and pressing the button to make a channel active. There is no intense, PC-based configuration software required.

While the sound quality of the Pro16™ has been very good, Pro64 Series™ offers excellent sound quality. I was able to A-B the 6416i and 6416o modules with a source in our mastering studio–a controlled listening environment–and the comparison was quite impressive, even at 44.1k. Again, there is no data compression in the audio stream. They obviously paid careful attention to component selection. These are things that really contribute to the sound quality, especially because compression varies the waveform enough for phase anomalies. These units retain stereo imaging because of consistent phase.

This is important when selecting a system used for splitting to a record room (see PPT slide 54). Signal to Noise is at an impressive 111db and cross-talk at 1k is 100db. Distortion is spec’ed at an acceptable .002% at -10dBFS.

You can configure your system in any number of ways in order to move signals to and from locations in your network. The beauty is, once the Cat-5 is in place, you can change your mind by simply locating boxes and activating channels. When one considers the cost of a 64-channel transformer splitter, which could run over $10,000 in some applications, you could easily realize savings that justifies the initial investment into this system. With the Pro16™ AV-P2 Output Module, we could utilize the network in distributed systems such as cry-rooms, lobbies, and other venues. Aviom has plans for releasing a software-based control solution that would transform the system into a widely versatile matrix based solution.

This is a well thought out system that is sonically and physically solid enough to spec into any system. Key to the success of the line will be the release of the much-needed 6416m – a 16-channel mic input module with remote controllable mic preamps, scheduled for release in early 2008.

This company just went way beyond making cool, little 16-channel mixers.