Thirty years ago, Washington State’s AudioControl Industrial began creating audio test devices for the pro installer/operator. They now manufacture distributed audio components to both pro and consumer audio markets. Their SA-3051 portable analyzer has been extremely well received amongst professional users and is integral to many system operators’ tool chests.
In 1997, AudioControl President Tom Walker unveiled the Iasys (essentially pronounced “I assist”) analyzer, which uses fuzzy logic algorithms to interpret gathered amplitude, frequency and time information to give the user not just data, but also answers for the purpose of setting up and testing performance of audio components/systems. Upon its release, Frank Wells positively reviewed Iasys within the pages of PAR as a worthy tool for “operators who are not highly technical.” Now, 10 years later, we revisit this successful, user-friendly product and examine the new components of its Version 3.0 software.
Iasys is portable, self-contained and exists without the need for a computer to operate. It is four inches tall by 10 inches wide by 13.5 inches deep, weighing nine pounds. A flat response calibrated measurement microphone and travel case is included within the $3,995 kit. The Iasys unit performs automatic tests categorized as crossover, delay and polarity, coherence and "equalizable’ spectra, and limiter.
A look at the front panel topology reveals 32 control buttons clustered into three groups, a large (2 x 3.5 inches) gas plasma display, jog wheel, power switch, XLR mic inputs 1 and 2, XLR output and banana speaker input. Inputs and outputs are located on the left side, the display is centrally located and the control groups surround the display. The three control groups are delineated as automatic test, octave select and manual tests with function keys. Enter and Quit buttons reside under the power switch, and a Help button is included under the right-side located jog wheel. The automatic test group has test and recall buttons, as well as buttons to activate the aforementioned automatic tests. The octave select group has 11 octave center points from 20 Hz to 20 kHz for quickly tuning a selected frequency. The manual test group with function keys selects the function of the on-board signal generator with the options of pink noise, pure sine wave and sweep sine wave test signals. Around back, the rear panel offers an IEC power connector, fuse holder, parallel printer port and serial cable connector.
Iasys contains four groups of non-volatile memory (A, B, C and D) within 32 banks for a total of 128 memory positions. These are points to store information on a specific system from each test for later retrieval by either performance verification or printout. When a specific bank in memory is selected for a system, all following tests will be stored there.
Upon power up, Iasys runs a self-calibration program that lasts a couple of seconds. After this, the automatic tests can be made. It is advised that the system to be tested must achieve a minimum of 85 dB or 18 dB above the ambient noise floor at the microphone for Iasys to run its tests; otherwise you may get error readings, so keep this in mind. (Also remember that hearing protection is a good idea during these tests, as the acoustic energy level of the sweep tones and pink noise may be quite high.)
Testing installed and portable professional sound systems
Fuzzy logic algorithms interpret data to provide system settings; 1/48th octave receive filters; signal generator with pink noise and sweep functions; automatic test functions; 128 non-volatile memory positions; large numeric real time SPL display; auto ranging 1/3rd octave spectrum analyzer
AudioControl Industrial | 425-775-8461 | www.audiocontrol.com
- Fuzzy logic algorithms provide answers from data
- No computer needed
- Automatic tests for quick system setup
- Built-in signal generator
- Lack of popular digital device interfaces
- A few glitches when toggling the automatic tests
Iasys is a well-crafted portable test system that has the needs of the audio contractor in mind.The initial test is for bandwidth, which is the basis for the other automatic functions. This test sends out pink noise to the drivers and calculates energy bandwidth characteristics, during which it sets Iasys’s internal mic preamp and testing levels. Then, a thorough analysis of the signal returned via microphone commences with a 1/48th octave sweeping receive filter.
I began tests with the Iasys utilizing a powered 3-way speaker system in a free-air environment (outside). I connected the output of the analyzer to my powered system and set the microphone at my listening position (console) toward what I perceived as the acoustic center of the speaker system. After completing the crossover frequency test, storing the subs and mid/high packs in banks A and B, and setting the recommended cutoff frequency, respectively, I moved to the crossover level test. After seeing the horizontal bars line up on the user interface graph to set levels, I was ready to try the delay/polarity test. Although I was in a free air environment and not utilizing delay speakers, I was interested if my polarity was correct and what the distance from the speakers to my measurement mic position (console) was, according to Iasys. After a series of test tones, I was informed that my system polarity was correct and that my console was about 40 feet from the speakers.
I then tried the equalizable spectra test, and found that while the system was fairly linear there were two areas of concern that were shown in the audio spectrum graph by being omitted from the chart. I was then able to toggle back to the coherence chart to see where nulls or distortion made the system unable to be EQ’ed according to Iasys, possibly from comb filtering effects or other induced distortion. These bands were quite narrow and forgivable considering the circumstances, so I adjusted my system EQ to flatten out any peaks in response.
When I inserted my console and applied some familiar program material, I noticed the system seemed a bit more even-tempered and had a bit more headroom. Although the crossover and EQ adjustments weren’t too far off from my initial (pre-Iasys) settings, it was an eye opener. If the system was new and/or in an unfamiliar setting, I could see how Iasys would be a quick and painless way to get up and running in a hurry.
The unit I used is the current updated version, or Version 3.0. New features include an auto-ranging 1/3-octave spectrum analyzer function that begins when depressing the manual pink noise button, and a large numeral, real time SPL display which can be read at quite a distance … very handy.
I encountered a few glitches when toggling the automatic tests; at times it seemed I could not proceed to another function or it was “frozen” and had to use the quit button. (The manufacturer responds that a software revision upgrade to Version 3.6, complimentary to anyone who has purchased 3.0, addresses these glitches. — Ed.) Unfortunately, I could not run the limiter test because it requires a speaker level output send from an amplifier, and in this particular instance my powered speakers precluded that. Ten years after Iasys’s debut, powered speakers with their own internal limiters have become far more prevalent, and AudioControl may want to address this.
I did not try to print out a report or connect with an outboard computer via the serial port … my bad. I would mention there are other various pro audio device connectivity preferences out there in the form of USB, AES/EBU and Ethernet, but that involves a whole other plateau of design criteria that Iasys may or may not need. But as a stand-alone unit, it shines.
To say that the Iasys is not your typical real time analyzer is an understatement. It truly gives answers, as well as data. Additionally, I found the unit to be very durable with a good fit and finish in typical AudioControl fashion. Iasys is a well thought out device for anyone who designs, installs and operates audio systems … no computer necessary.