Field Report: ATI ADAC-2

August 1, 2008

Most broadcast facilities need to convert analog audio to digital or digital to analog. Many times this may need to happen in a critical air or program chain so a high quality, reliable conversion is needed.

ATI has come through with its ADAC-2, two-channel, 24-bit, 192kHz analog-to-digital, digital-to-analog and sample-rate converter. The 1RU device has a front panel that is easy to read and understand. It allows users to toggle between all three options with a single pushbutton. The mode button lets you switch between A/D, D/A, and SRC setups. The front panel also has a bright level meter, gain adjustment and clearly displays sample rate, word length and input selection.

Performance at a glance
Three independent signal paths
Dedicated I/O for each converter section
SNR >100dB
Sample rates from 32kHz to 192kHz
Up to 24-bit word length
Front-panel lock
Stores and recalls three separate setups
XLR, RCA and Toslink audio I/O

Moving back

The rear of the unit is just as nicely laid out. Everything is clearly labeled and the connections are not crammed together making it easy to dress cables to the unit. There are balanced and unbalanced analog, transformer-isolated AES-3, S/PDIF digital, a Toslink optical input, BNC outputs for sync and an XLR input for sync in. The stable, low-jitter, internal clock can be set up with a variety of sync inputs, including word, bit and external source. It also has an internal power supply and does not rely on wall warts or any other kind of external transformers.

With all that said, the audio performance of the ADAC-2 is just as impressive as the layout of the unit. The sample rate conversion portion of the unit can take place at 16, 18, 20 or 24 bits at sample rates from 32kHz to 192kHz. The unit also has plenty of headroom with a dynamic range greater than 100dB and a THD of less than 0.003 percent. The digital to analog portion is different from the ADC in that it will auto select the sample rate of the incoming digital source. It also has an even lower THD of less than 0.001 percent.

Audio quality like this makes using the ADAC-2 for applications like STL and EAS conversion worry-free. I have used them to convert a digital program chain to analog to feed analog STLs. I have also used the D/A-A/D to insert an analog audio processor into an entirely digital air chain. The ADAC-2 allows me to take my digital program chain, convert it to analog, feed my audio processor and then take analog out of the processor and convert it back to digital to feed the air chain. In this application the unit's audio quality really shines. There is no noticeable loss or noise in the back-and-forth conversion. That is mission-critical when it comes to program and air chains.

ATI worked with Day Sequerra's engineering department to develop the ADAC-2. The unit shows the commitment from both companies to help redefine what many people think of ATI from years ago. It sports an ATI Digital Audio logo, signifying a high-end digital product. This is really a quality A/D-D/A-SRC unit from a whole new ATI.


Smith is the broadcast system supervisor, Clear Channel NYC, and chief engineer, WWPR-FM.

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.

These reports are performed by the industry, for the industry. Manufacturer support is limited to providing loan equipment and to aiding the author if requested.

It is the responsibility of Radio magazine to publish the results of any device tested, positive or negative. No report should be considered an endorsement or disapproval by Radio magazine.

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