Field Report: Klotz Digital Aeon

August 1, 2005

Have you ever been at a trade show and come up to a booth where you see a sign, "Put your card in the box for a chance to win?" So, you pull out your card, put it in the box and figure that's the end of that. After all, I never win anything.

Well, that is what happened to me at NAB2004. I put my card in the box at the Klotz Digital booth thinking that the grand prize was just too good to really win. Guess what? I won! The grand prize was a complete Aeon digital audio console.

The console arrived in December, just a week before Christmas. The timing was good because we needed a new console in a small production room. The early music production digital console no longer fit our needs. We needed more output channels than the old console could provide. In particular, we needed to create a mix-minus, which was difficult to do in a way that semi-skilled operators could understand.


The console consists of three major components: the control surface, an electronics frame and a power supply. In addition, a USB keyboard and mouse, and a cable to connect the control surface to the electronics module were in the package. All documentation is on a CD-ROM. The power supply is a 2RU cage with what appears to be a conventional computer power supply inside. It has a captive cable that connects to the electronics card cage.

Performance at a glance
Dynamics and EQ control for each channel
Extensive mix-minus capabilities
Level meters for all busses and selected inputs
Cost effective, router based system
16-character channel name displays
Low-profile (1”) design
Table-top mounting
Split or straight console options
GUI-based setup

The electronics frame is the heart of the system. Our unit came configured with one eight-input analog card, one eight-input digital card, one eight-output digital card and two eight-output analog cards. In addition, two DSP cards were included that are required for operation of the unit. The unit has connectors for a VGA output, PS2 keyboard and mouse, USB connectors, RJ-45 and several other connectors normally associated with a computer. All analog and digital audio input and output connections are on 15-pin DB connectors. Some of the connectors on the unit are noted in the manual as not being used. A 36-pin DB connector is also included for GPI input and output connections.

The control surface connects to the electronics frame with a 15-pin DB cable. The control surface in our configuration consisted of three four-fader channel modules and a master/monitor module. The system will support two to five channel modules. The modules may be separated for more flexible control room layouts. The control surface has a clean, low profile, high-tech look. The only thing we had to add to the system was a monitor. We chose a 17" black, flat screen monitor to complement the look of the control surface.

I began by planning the installation. While the total number of inputs and outputs was no problem for our small control room, it did take some thought to make sure we had enough analog inputs for those devices that require it. For instance, DAT machines with AES outputs were no problem, but we needed to reserve space for our remote inputs, cassette machines and analog tape. (Yes, we still sometimes need to play those through our system.) I used a spreadsheet to help outline the inputs and outputs. Once I had this figured out the next step was to set up the software of the console.

The Vadis frame handles all the audio functions of the console.

The software was intuitive and easy to use once I had gone through the procedure in the setup manual. The software allows you to assign labels to the various inputs and outputs. The input labels show up on the control surface as the inputs are assigned to the channels. Once the keyboard and mouse are removed (you can also perform the setup with a computer connected to the RJ-45 connector) users cannot change the setup. Each output can be assigned to one of the seven buses in the console (two of them are mono for mix-minus uses) or one of the four monitor channels.

Users have the ability to change which input is assigned to which fader channel, as well as the more typical user functions on an audio console. However, the real power of this console appears when you press the select button for any channel. The EQ and dynamics control window pops up on the monitor display. The EQ has a high and low frequency shelf function, as well as two full parametric sections. The dynamics section has a compressor and expander with full control including an “over-easy” option. The monitor section can independently control the four monitor channels for source selection and volume. An auto-cue function can be activated to allow instant monitoring of channels put in cue without playing with the monitor controls. Two of the monitor channels can be ganged so one follows the other. This is useful when you want one to feed monitor speakers and the other to feed headphones.

Klotz Digital

While the console can save several snapshots of the controls, there appears to be no way to lock them so a user cannot change them inadvertently.

The console has several other features that would be useful in an on-air situation that we are not using, such as the ability to control other devices from the console controls.

This is a flexible system that would be at home in most radio stations.

Carter is chief engineer of WFMT, Chicago.

Editor's note: Field Reports are an exclusive Radio magazine feature for radio broadcasters. Each report is prepared by well-qualified staff at a radio station, production facility or consulting company.

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