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Field Report: Aphex Model 2020 MkIII
With the ranks of Hispanic broadcasters getting longer everyday, having an edge on the competition can make a difference. One important element in achieving that edge is delivering the highest quality product possible to our listeners. We put tremendous effort into not only the programming and direct community involvement but also the audio quality. The days of Spanish language programming being a niche format on the AM dial have given way to being some of the top-rated FM stations in the nation's top markets.
Our stations' programming runs from Spanish CHR to tropical, with concert remotes, mixing music live from local night clubs and lots of listener call-ins. Within this eclectic mix we often get programming material produced in parts of the world that have lower production standards. Even material produced here is often done in home studios with variations in quality.
It is my responsibility to achieve consistently high audio quality on air using all the sources of varying quality, but without processing the distinctiveness out of the source material. It also has to be loud if you are going to be a successful commercial station in the Los Angeles, New York and Chicago markets.
|Performance at a glance|
I've been using Aphex products for years, and my stations have used the first and second generation Model 2020 processors with good results. I had not associated Aphex with maximum loudness boxes, so I was interested in listening to what the company had done with its latest iteration of the Model 2020, the MkIII.
The Model 2020 MkIII basic unit is a wide-band leveler, a four-band compressor and a split-band peak limiter with analog inputs and outputs. Options include digital I/O, a high frequency limiter and a stereo generator. This gives each installation the ability to configure the unit to its needs. We use the digital I/O and HF limiter options so that all the processing is done in the unit and the digital output is then fed to a Digit exciter.
The difference between this version and the two previous versions, the 2020 and the MkII, is that the leveler was changed to be more RMS detecting and the HF limiter has been changed to split-band design. Other changes in-cluded how the Automatic Limit Threshold, a patented element, was controlled. The improvements were quite noticeable with a more open high end.
The MkIII improved the performance of the HF limiter. According to Aphex, the slopes of the crossover filters in the MkII were not steep enough and clipping distortion could occur on sibilant peaks when the unit was driven hard. The MkIII has much steeper slopes and this problem has been solved.How does it sound?
You have to have deep, solid, clean bass for any music format, but especially for any dance or hip-hop genre. All versions of the 2020 deliver more bass than you could ever dream of — so much so you that you should set it up listening on full range speakers or else you can get so much bass that the typical car speaker will rattle out of the car door. The split band peak limiter allows the unit to generate so much bass. It uses the principle that bass clipping is actually an enhancement while mid and high frequency clipping can be irritating. The circuit analyzes the amount of mid and high frequency content and adjusts the clip point of the bass clipper, thus giving the maximum amount of bass for any input. Also, there are two shelving equalizers that allow you to further shape and enhance the bass.
One of the unique features of the 2020 is the Wave Dependent Compressor in each of the bands. It has a convoluted filter detection circuit that keeps the attack time fairly slow until a faster attack is needed. Slower attack times are typically better sounding than fast attack times, but slow attack times result in larger overshoots, causing the following limiter to work harder. This circuit sounds like a slow attack while also providing peak control. The bands can be linked, but only the slow time constants are connected. The result is the fidelity of a wide-band compressor but without the hole punching. When the bands are unlinked there is a dynamic EQ effect. To get the vocals out more consistently I unlink the bands. The vocals that had been buried become present and clear.
The high end of the MkIII is noticeably bigger and clearer than the MkII. The DJs have commented that their voices sound much more open and clean, and that is with running the processor heavily.
In tuning the MkIII I found that I could achieve different textures and sounds with small adjustments. That is in sharp contrast with other processors that have a character or sound that is their sound almost no matter how the unit is adjusted. All of the processing parameters on the 2020 can be adjusted on the front of the unit or via easy and intuitive software (for PC only). There are eight factory presets and 16 user presets. The only things that are not adjustable from the front panel or software are the digital input reference level and the digital output level. These must be adjusted by internal trimmers.
As part of our corporate commitment to quality we had been willing to lose a little bit of loudness for higher fidelity. With the 2020 MkIII we have been able to get consistently high audio quality with each song retaining its own character. Announcers' voices are clean, present, natural and big, and call-ins are clear and intelligible.
Kramer is vice president of engineering for Big City Radio, Los Angeles.
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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