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A Retrospective
White Instruments, Inc. was founded in 1953 by Gifford White to specialize in the design and manufacture of precision filters and networks. The initial product line included twin-T notch networks that became standard production components for many manufacturers such as Westinghouse, General Electric and Beckman Instruments. Operational amplifiers were quickly added to make White Instruments one of the pioneer manufacturers of active filters for research and industrial use. By including L-C wave filters, using precision toroids wound in-house, a full range of techniques were offered to cover the audio and sub-audio ranges.
Customers for these products included the military, government agencies, universities, research institutions, and private industry. White Instruments has built and continues to build filter comb sets for high resolution sonar, infrasonic filters for seismic and ocean wave studies, and filters for scientific and industrial purposes such as those used in spectrometers and engine balancing equipment. One such set of frequency selective devices flew in orbit with the Orbiting Astronomical Observatory: Another helped locate the hydrogen bomb lost in an air accident off the coast of Spain in 1966.
White Instruments has always maintained an engineering and development staff with quick turnaround capability to give customers one-of-a-kind designs for little or no premium. Our ability to converse with the customer and understand his problem has led to the realistic specification of filters for each unique application at minimum prices.
White Instruments began its association with the audio industry in 1962 through work with Dr. C.P. Boner. Dr. Boner's theories involving feedback in sound systems, room ring modes, and room-sound system flattening techniques were proven utilizing instrumentation and filters designed by White Instruments. Many will remember the Model 130 Test Set developed by White Instruments utilizing vacuum tubes and iron core inductors, as being the first self-contained broad band test set for measuring room characteristics. The Model 134 Test Set followed, incorporating integrated circuit operation amplifiers to band limit pink noise. Finally, the Model 136 Test Set was developed using sophisticated digital delay line techniques to band limit the noise test signal. Our Model 135 Level Averager was the first instrument available for averaging the output of three microphones to alleviate the chore of "walking the house" with a sound level meter. Some of the instruments are still in use.
In 1974, White Instruments introduced the first all solid state real time analyzer, the Model 140 Sound Analyzer. The use of a light emitting diode readout received wide acceptance. A substantially more advanced instrument, the Model 200 Signal Analyzer, was introduced four years later. Being a modular microprocessor based analyzer, the user can tailor it to his own needs with plug-in cards.
From the beginning of Dr. C. P. Boner's studies, White Instruments manufactured the filters necessary for adjusting sound system response to complement room response. The famed "tapped toroidal inductors" as manufactured solely by White Instruments under license from Boner Associates. These tapped inductors are still considered the best way to introduce narrow band correction into a sound system to tame bothersome feedback frequencies and room ring modes.
White Instruments introduced the first passive broad band equalizers commercially available for the equalization of room-sound system response. The Models 3040, 3100 and 3500 passive EQs are still found in older installations today . . . and they're still working. The many variations of equalizers manufactured by White are proof of our flexibility and extraordinary capability of responding to the needs of the industry.
In 1975, White Instruments judged the state-of-the-art in integrated circuitry had advanced sufficiently to develop an active equalizer. Calling on our experience in network design and active filter circuitry, we introduced the Series 4000 Active Equalizers. These models utilize a unique circuit incorporating precision L-C components in a negative feedback design thus assuring a high degree of stability. Other circuit features, including careful buffering, provide for the best addition possible of adjacent channels in single resonator designs. The use of modern circuit techniques insures good signal to noise ratio.
Nineteen seventy-eight marked a year of innovation for White Instruments. Drawing from the vast experience gained from the users of our equipment, White pioneered the use of One-Sixth octave equalizers for small room tuning.
In 1984 White Instruments was purchased from the White family by Carl Van Ryswyk, a 20 year veteran of the company and its chief engineer. This period saw the introduction of a series of graphic equalizers that have evolved into the current models: the 4828, a single channel one-third octave equalizer, the 4856, a dual channel, one-third octave equalizer with a separate sub-bass output, and the 4675, a dual channel two-thirds octave equalizer.
Other product introductions include the Model 4700, which was among the first digitally controlled analogue equalizers ever produced. In 1992 White Instruments introduced its first multipurpose digital signal processor, the Model 5000. Since then two new additions, the 5024 and the 5022 have been released. Both models provide parametric equalization, crossover, delay compression and limiting and allow the user to assign any filters to any input or any output providing a high degree of flexibility.
Other products in the current White Instruments line include the digitally controlled Model 4710, the only one-sixth octave, graphic EQ available in the market. The 4710 was designed for applications where speech is the predominant program material and audibility is extremely important.
Control of White Instruments changed again in 1996 when the company was purchased by a group of investors. White Instruments began development of new software interfaces for computer control of its digitally controlled signal processing products.
First shown at NSCA '98, the White ParaMedic line established the benchmark for sound system equalizers by utilizing the very latest 32/40 bit, floating point math DSP engine in their new multifunction design. A one rack space unit is powerful enough to service every equalization requirement in a one or two channel sound system. Seventy filters are available to be simultaneously configured as: parametric and very narrow notch filters, one-third or one-sixth octave graphic filters, high-pass, low-pass and shelving filters. The ParaMedic (+) adds delay to the package.
At AES 1998, White introduced the ParaMedic X and the ParaMedic Code Pink. Both encompass all of the features of the basic ParaMedic unit. The ParaMedic X adds digital limiting, one or two channel operation, digital two-way crossover with the choice of Bessel, Butterworth or Linkwitz-Riley characteristics: slopes from 6dB to 48dB per octave and customized asymmetrical slopes. The ParaMedic Code Pink is a surgically precise digital parametric masking generator with dual 32-bit white/pink noise source with nearly Gaussian characteristics and a pair of one-third equalizers.
The industry demanded DSPs with more processing power, better channel mixing, input delay and more output channels. White Instruments responded with the ParaMedics 22, 24, 26, and in 2003, the ParaMedic 48.
In 2002 Carl Van Ryswyk was able to repurchase the assets of White Instruments and retain a few key people. Good companies die hard and Carl plans to rebuild a good, but smaller company and support the legacy products where parts availability allow.
White Instruments will continue to be the innovator in the new world of digital signal processors. We foresee developing products with greater processing power at greater speeds with greater cross-platform compatibilities. White Instruments will continue to be the company that others imitate. While our name is as generic as the general terminology, it's also a generic term in the audio world. How many times have you heard someone say, ". . . and it's just as good as a White." Let's set the record straight. All of the products in the White Instruments line are "As Good As It Gets."
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