When Salem Los Angeles built its new studios, the talk studio was built to be functional as well as visually attractive. This included large windows for easy viewing in and out of the studio. Unfortunately, this architectural decision resulted in an acoustic problem. The room had a reverberant sound that was obvious when more than one microphone was in use. Since covering the windows was not a practical option, another solution was needed. Mark Pallock, Salem Los Angeles chief engineer, explains.
"We built a huge talk studio with glass on three sides. When we turned all six mics on at one time, a horrendous acoustical feedback resulted from sound bouncing off the glass. It sounded like everyone was speaking inside a tunnel." The cure to the problem was the downward expander in the 528E. Pallock continues, "The mic processor electronically shuts off the mics that are not being used. It works very well."
The 528E is a self-contained voice processor that performs six separate functions: microphone preamplification, de-essing (sibilance removal), compression/limiting, downward expansion, parametric equalization and voice symmetry alignment. All six processors may be used simultaneously. While the 528E is called a voice processor, it is perfectly suited for any audio signal. The unit includes a mic-level input and a line-level input. A front-panel switch selects the input source.
In all, the Salem facility has eight units installed in its studios including the Symetrix 528, the predecessor to the 528E. The four stations, KKLA-FM, KEZY-AM, KIEV-AM and KFSH-FM, all use different microphones including the AKG C-647, Electro-Voice RE-20, Neumann TP-103 and Sennheiser MKH-416. The 528E provides just the right amount of processing to make each microphone sound great.
Pallock points out that each station uses each processor differently. "On KKLA we are only using the downward expander. On one AM we are using the equalization. That station has a very narrow antenna bandwidth. The equalization helps us achieve a very punchy sound on the air. The 528E gives us a loud and clean sound."
Each processing section of the 528E features a full complement of controls in an easy-to-use layout. Separate LED meters monitor microphone gain and dynamics gain reduction functions to facilitate quick and accurate adjustment of controls. As a dedicated single-channel voice processor, the 528E delivers the same processing power found in a recording studio signal chain. With the 528E you get the control you need, without the cost or complication of separate units.
Each processing function is routed to the next via the rear-panel jacks. A front-panel switch enables a hard-wire bypass of the section, but the rear panel jacks can be used to setup the processing sections in a different order. While not often used, this does provide another level of flexibility to the 528E.
The 528E works with any professional microphone. The mic preamp's gain is variable up to 60dB, and 48 volt phantom power is provided for condenser mics. A switchable 15dB pad reduces gain in front of the mic preamp to prevent distortion in super close micing situations. A front panel switch selects between microphone or line input. Both inputs are transformerless and are equipped with filters to prevent radio frequency interference (RFI).
The Symetrix program-controlled Integrated Dynamics Processing (IDP) techniques combine the best attributes of compressor/limiters and downward expanders. The compressor/limiter maintains uniform levels while the downward expander eliminates pumping, breathing and noise build-up. Because it is program controlled, the 528E's dynamic range processor responds quickly to transients and gently to smaller level changes. The controls provided are Expand Threshold, Compress Threshold, and Compression Ratio. The three-band parametric equalizer performs both creative and corrective operations, with bandwidth variable from 0.3 octaves to 4 octaves, 15dB boost/cut and overlapping frequency ranges.
Regardless of your choice in microphones, the 528E can make inexpensive microphones sound great and high-quality microphones sound even better.