Symetrix 527E Voice Processor

The 527E by Symetrix, Inc. of Lynnwood, Wash., is a combination microphone preamplifier/compressor/ limiter, expander and parametric EQ with high- and low-pass filters in a single-rack space device. Symetrix claims that this processor includes all the dynamic range and equalization processing required to optimize the performance of a microphone (or line level signal source) in a variety of applications.
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The 527E by Symetrix, Inc. of Lynnwood, Wash., is a combination microphone preamplifier/compressor/ limiter, expander and parametric EQ with high- and low-pass filters in a single-rack space device. Symetrix claims that this processor includes all the dynamic range and equalization processing required to optimize the performance of a microphone (or line level signal source) in a variety of applications. The 527E ($599) is based on the previously released 528E, which is popular with broadcasters. The 527E is aimed more toward the contractor market, however - it does not provide the de-essing and voice symmetry circuitry found in the 528E.
Product PointsApplications: Live sound; fixed-installation venues

Key Features: Comprehensive automation; two Lexicon effects units; two dynamic processors; 16 mic/line (expandable to 32) inputs; AES/EBU, S/PDIF and TDIF digital I/O standard

Price: $4,799

Contact: Spirit by Soundcraft at 800-255-4363; www.spiritbysoundcraft.com.

Plus

+ Numerous standard-equipped analog and digital I/O

+ Excellent user interface

+ Flexible automation and routing

Minus

- Could use more dynamic processors

The Score: A well-thought-out live digital console with all the options an engineer could want - standard!
Features/In use

Front panel controls include (left to right): 20 to 60 dB microphone input gain control, microphone and line input mix control, expander threshold, compressor threshold and ratio controls, +/- 15 dB output gain control, expander/compressor and EQ/filter bypass switches, variable 12 dB per octave low cut (6 to 260 Hz) and high cut (3 kHz to 65 kHz) filter controls and parametric EQ section.

The parametric EQ is divided into low-, mid-, and high-frequency adjustment sections. The low section includes variable frequency (16 to 500 Hz) control, bandwidth (0.3 to 4 octave) control, and +/- 15 dB cut/boost control. The mid and high frequency sections have similar bandwidth and cut/boost parameters, but the mid varies the center frequency from 160 Hz to 6,300 Hz, and the high varies from 680 Hz to 22 kHz. LED multicolored diagnostic displays show input clip and mute status, expander and compressor ladder meters, output gain and clip meter and power indicator.

The rear jackfield has phoenix and XLR line level balanced outputs, and XLR mic level balanced outputs, both with a low impedance of 200 ohms. A phoenix-style mute control connector is centrally located. Residing far right are a phoenix and XLR style balanced line level input (10 kohms) and transformerless balanced XLR mic level input with ö15 dB pad and phantom power switch.

Initially, I used the 527E to smooth out a lead vocal track on a live-to-ADAT recording. I was impressed with the results. I ran the lead vocal utilizing a Shure SM58 microphone through the unit and immediately obtained a useable sound. The expander helped clean ambient signal from the primary feed and the comp/limiter smoothed out annoying plosives and varying microphone technique exhibited by a performance-distracted singer. The interactive LED display helped to refine settings easily. In this application, the 527E is like having a dynamics processor built into a channel strip.

My next application was a podium microphone at a high school auditorium. This was the primary microphone for the system and there were constant complaints about rumble, background noise and feedback from the system when the podium was placed center stage (where the floor input jack was located). The portable podium was dead center, located directly under the loudspeaker cluster; choir microphones located toward the back of the stage were performing fine.

After speaking with the administration and determining that repositioning the podium for student assemblies was out of the question, I decided to try the Symetrix unit. It turned out to be the right tool for the job. The dynamics section helped to tailor microphone response from soft-spoken kids to booming teachers, while saving the system from users who grab the gooseneck or bang on the podium.

Meanwhile, the parametric EQ notched out ring frequencies and the low-cut filter got rid of any annoying rumble. Sonically, the unit was excellent and I had no problem with EMR/RFI that could degrade the quiet (high signal vs. noise) performance. Of course, balanced operation, and using interconnects with a tight twist cable help in these aspects.

The only aspect of the unit I didn't test was the mute function. This would probably be used for life/safety override or even as a cough drop in a broadcast situation.

Summary


The Symetrix 527E is built like a brick with a heavy-gauge steel chassis. It is easy to read with the dark blue faceplate and bright white graphics. Nice tactile feel and responsive controls give the user an overall impression of quality. The unit is a superlative all-in-one problem solver - nice to use as a channel insert with a mixer for a problem microphone, as a single source directly into an amplifier for a venue, or as a mic preamp for location recording. The 527E is a great wrench for any audio toolbox.

Contact Symetrix at 425-787-3222