234:(a Philadelphia suburb). His first two products were the DH-101 preamplifier, followed a few months later by the DH-200 companion power amplifier. Added later was the rugged DH-500 stereo amplifier, which was rated at 255 watts per channel and saw great success in home, studio, and live environments. The amplifiers were notable for their early use of new, more-powerful
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Following the Dynaco business model, these products were available in both kit form and factory assembled. The units were acclaimed for their breakthrough sound quality and exceptional value, and are still highly prized today. Hafler made several different models of amplifiers and preamps over the
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Mike Belitz, CEO and
President of Ultimate Support, in a venture with Vancouver, B.C. Private Equity Firm, Regimen Partners, have acquired Radial Engineering Ltd. and its diverse catalog of brands that include Primacoustic, Tonebone, Reamp, Hafler, Dynaco, Jensen Transformers and Iso•Max.
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of the period, which attempted to reconstruct a surround sound field from a two channel recording. It had been observed that ambient sounds in a concert, such as applause or coughs from the audience, are generally received in a non-correlated phase by the stereophonic
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The Dynaco QD-1 Quadaptor was based on this idea, adding a variable resistor to control the volume of the rear speakers. This passive method worked fairly well compared to the
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169:. This company was primarily in the business of designing and manufacturing transformers for tube amplifiers. Around this time Hafler and Keroes popularized the
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The Hafler brand was purchased by
Canadian based Radial Engineering Ltd in 2014. Radial planned to re-launch the Hafler brand of high-fidelity audio products.
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Hafler sold his company to the
Rockford Corporation in 1987. Today, the Hafler company primarily makes products for the professional sound market.
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years. Hafler products were also a solid foundation for improvements through later upgrades and modifications, installed both by
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145:(February 7, 1919 – May 25, 2003) was an American audio engineer. He was best known for his work on an improved version of the
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to enable much lower distortion at higher power, in a very economical fashion. The new designs were less vulnerable to
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or loss of stereo separation in the front speakers was generally less than 2
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output-stage for audio amplifiers. However, the partnership did not last.
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total) between the live feeds to the front speakers. The
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Hafler was inducted into the Audio Hall of Fame in 1984.
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In 1950, Hafler founded
Acrosound with his colleague
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In 1977, Hafler founded the David Hafler company in
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125: 1942; died 2001)
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16:American audio engineer (1919–2003)
357:Sims, Gayle Ronan (May 27, 2003).
19:For the American neurologist, see
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457:20th-century American engineers
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50:West Philadelphia, Pennsylvania
390:Willis, Barry (June 1, 2003).
307:Hi-Fi News & Record Review
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462:Quadraphonic sound engineers
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299:"A year of surround-sound"
81:University of Pennsylvania
69:Philadelphia, Pennsylvania
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364:The Philadelphia Inquirer
452:American audio engineers
392:"David Hafler 1919–2003"
102:and David Hafler Company
359:"David Hafler Obituary"
176:In 1954 Hafler founded
232:Pennsauken, New Jersey
328:. September 11, 2014.
147:Williamson amplifier
371:on February 6, 2007
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344:Radial Engineering
340:"We have big news"
326:Radial Engineering
112:Gertrude Schwinger
271:Awards and honors
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63:(2003-05-25)
61:May 25, 2003
30:David Hafler
447:2003 deaths
442:1919 births
397:Stereophile
221:microphones
153:circuit of
436:Categories
281:References
182:Ed Laurent
149:using the
87:Occupation
42:1919-02-07
406:0585-2544
205:crosstalk
161:Biography
133:Children
236:MOSFETs
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107:Spouse
100:Dynaco
302:(PDF)
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58:Died
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