Acoustic Research AR - 3a " Cutaway " Display Speaker, Special Unit, Extremely Rare
Item History & Price
Acoustic Research AR-3a "Cutaway" Display Loudspeaker For Display Rare, Hand-Built (by AR) Display SpeakerThis Unit can be shipped worldwideLast of the display versions built and possibly the last one existingRef. AR-0901
AR-3a "Cutaway"Loudspeaker Display SpeakerThisrare AR-3a "Cutaway" from Acoustic Research was ashow-demonstration version of the AR-3a, hand-made by AR personnel in the late 1960s for trade shows and for the AR Music Rooms. These AR-3a "Cutaways" were ha...nd built in AR's Cambridge factory with a removable side section to observe the interior and a functioning woofer with part of the cone removed. It is thought that there were only three of these speakers ever fabricated (according to Sumner Bennett, National Sales Manager at AR at the time), and that two were dismantled by AR and destroyed. This last speaker, shown here, was purchased by and belonged to Delrama International of 1140 Broadway, New York, NewYork. This AR-3a "Cutaway, " which has no serial number, was to be displayed inEurope, Asia and other parts of the world. There is no clear evidence that it was ever shipped abroad or ever used as a display unit. The AR-3a "Cutaway" unit has a standard AR-3a shipping carton in addition to an outer AR carton that is slightly larger for extra protection. This"Cutaway" was not designed to have functioning midrange and tweeter drivers. Only the woofer was intended to function as a demonstration of the excursion of the cone, pumping back and forth at 5 Hz with input from an audio oscillator (such as the Hewlett-Packard Model 200CD or similar) and power amplifier. This was done so that hi-fi enthusiasts couldobserve the operation of the AR acoustic-suspension woofer system.ThisAR-3a "Cutaway" is in excellent, original condition, and it has beenstored for many years and displayed only once for the October, 1994 "AR 40th BirthdayParty" on the east balcony of Grand Central Terminal in New York City.Thisis a very special Acoustic Research loudspeaker and would make a unique andvery special centerpiece to display with an AR speaker collection. _______________________________________________The Acoustic ResearchAR-3a Loudspeaker General Description:TheAR-3a is a 3-way, full-range, 4-ohm acoustic-suspension loudspeaker—technicallya bookshelf speaker for very sturdy bookshelves—which includes the well-known AR 12-inchacoustic-suspension woofer, dome midrange and tweeter drivers, based on theoriginal AR-3. TheAR-3a was designed by Chuck McShane and Roy Allison of Acoustic Research, Inc., and the speaker was introduced at the New York High Fidelity Music Show inOctober, 1967. The basic design goals ofthe AR-3a were originally established in 1965-1966 by AR with the objective of improving the already excellent off-axisdispersion of the renowned AR-3. Theresult was a speaker containing one of the widest and most uniform midrange andtreble dispersion of any forward-facing loudspeaker ever designed for homesound reproduction. Theacoustically sealed, heavily braced (nine internal braces screwed and glued tothe inside of the cabinet) AR-3a enclosure volume is 1.7 cu. ft., which is optimal forthe 41-43 Hz resonance frequency, and the woofer's suspension restoring forceratio is approximately 85% acoustic and 15% mechanical, far greater than nearlyall current consumer loudspeakers using the a/s design. For this reason—and the basic design of themotor system in the AR woofer—the AR-3a has lower harmonicdistortion than most conventional, current-design loudspeakers of a comparablesize. Julian Hirsch measured thewoofer's harmonic distortion at a power level ten-times higher than usual test input voltages, and the distortionin the AR-3a's woofer was under 9% at 20 Hz, setting a new standard of lowdistortion, especially at this high-power testing. Thewoofer used in the original AR-3a speaker has a 9.6 lb Alnico-5 magnetassembly, cast-aluminum frame and a long-throw, 2-inch copper voice coilwith a linear excursion of 5/8-inch and a maximum physical excursion of 1.2inches. The midrange driver has a 1½-inchtreated-cloth dome (hemispherical) diaphragmwith 1½-inch copper voice coil on an aluminum former assembly. The midrange driver is highly damped withfiberglass pads under and above the dome assembly itself. The magnet assembly is a large ferrite unit. The AR-3a tweeter uses a ¾-inch treated-paperdome diaphragm—similar to theoriginal AR-3 phenolic-dome tweeter—suspended by urethane-polymer foam pieces in the outsideportion of the voice coil with a layer of clear butyl-rubber sealing the outsideof the magnetic gap. The magnet assemblyis ferrite. The drivers have LCRcrossover frequencies of 575 Hz and 5, 000 Hz. Thespeaker's impedance ranges from 2.7 – 4.9 ohms, and the speaker isapproximately 0.7% efficient, meaning that an amplifier capable of at least 25 watts-per-channel into 4 ohms is the minimum suitable power. The AR-3a physical dimensions are 14” x 25” x11-3/8.” The AR-3a’s net weight, each, unboxed, is 54 lbs., and in the double shipping carton 64 lbs gross. ©ARHPGDevelopment 1999-2019 USPTO All Rights Reserved- COPYRIGHT NOTICE -
All content seen here, including HTML coding, photos, artwork and text contentis copyright protected as intellectual property and may not be used withoutwritten permission from its owner.
AR-3a "Cutaway"Loudspeaker Display SpeakerThisrare AR-3a "Cutaway" from Acoustic Research was ashow-demonstration version of the AR-3a, hand-made by AR personnel in the late 1960s for trade shows and for the AR Music Rooms. These AR-3a "Cutaways" were ha...nd built in AR's Cambridge factory with a removable side section to observe the interior and a functioning woofer with part of the cone removed. It is thought that there were only three of these speakers ever fabricated (according to Sumner Bennett, National Sales Manager at AR at the time), and that two were dismantled by AR and destroyed. This last speaker, shown here, was purchased by and belonged to Delrama International of 1140 Broadway, New York, NewYork. This AR-3a "Cutaway, " which has no serial number, was to be displayed inEurope, Asia and other parts of the world. There is no clear evidence that it was ever shipped abroad or ever used as a display unit. The AR-3a "Cutaway" unit has a standard AR-3a shipping carton in addition to an outer AR carton that is slightly larger for extra protection. This"Cutaway" was not designed to have functioning midrange and tweeter drivers. Only the woofer was intended to function as a demonstration of the excursion of the cone, pumping back and forth at 5 Hz with input from an audio oscillator (such as the Hewlett-Packard Model 200CD or similar) and power amplifier. This was done so that hi-fi enthusiasts couldobserve the operation of the AR acoustic-suspension woofer system.ThisAR-3a "Cutaway" is in excellent, original condition, and it has beenstored for many years and displayed only once for the October, 1994 "AR 40th BirthdayParty" on the east balcony of Grand Central Terminal in New York City.Thisis a very special Acoustic Research loudspeaker and would make a unique andvery special centerpiece to display with an AR speaker collection. _______________________________________________The Acoustic ResearchAR-3a Loudspeaker General Description:TheAR-3a is a 3-way, full-range, 4-ohm acoustic-suspension loudspeaker—technicallya bookshelf speaker for very sturdy bookshelves—which includes the well-known AR 12-inchacoustic-suspension woofer, dome midrange and tweeter drivers, based on theoriginal AR-3. TheAR-3a was designed by Chuck McShane and Roy Allison of Acoustic Research, Inc., and the speaker was introduced at the New York High Fidelity Music Show inOctober, 1967. The basic design goals ofthe AR-3a were originally established in 1965-1966 by AR with the objective of improving the already excellent off-axisdispersion of the renowned AR-3. Theresult was a speaker containing one of the widest and most uniform midrange andtreble dispersion of any forward-facing loudspeaker ever designed for homesound reproduction. Theacoustically sealed, heavily braced (nine internal braces screwed and glued tothe inside of the cabinet) AR-3a enclosure volume is 1.7 cu. ft., which is optimal forthe 41-43 Hz resonance frequency, and the woofer's suspension restoring forceratio is approximately 85% acoustic and 15% mechanical, far greater than nearlyall current consumer loudspeakers using the a/s design. For this reason—and the basic design of themotor system in the AR woofer—the AR-3a has lower harmonicdistortion than most conventional, current-design loudspeakers of a comparablesize. Julian Hirsch measured thewoofer's harmonic distortion at a power level ten-times higher than usual test input voltages, and the distortionin the AR-3a's woofer was under 9% at 20 Hz, setting a new standard of lowdistortion, especially at this high-power testing. Thewoofer used in the original AR-3a speaker has a 9.6 lb Alnico-5 magnetassembly, cast-aluminum frame and a long-throw, 2-inch copper voice coilwith a linear excursion of 5/8-inch and a maximum physical excursion of 1.2inches. The midrange driver has a 1½-inchtreated-cloth dome (hemispherical) diaphragmwith 1½-inch copper voice coil on an aluminum former assembly. The midrange driver is highly damped withfiberglass pads under and above the dome assembly itself. The magnet assembly is a large ferrite unit. The AR-3a tweeter uses a ¾-inch treated-paperdome diaphragm—similar to theoriginal AR-3 phenolic-dome tweeter—suspended by urethane-polymer foam pieces in the outsideportion of the voice coil with a layer of clear butyl-rubber sealing the outsideof the magnetic gap. The magnet assemblyis ferrite. The drivers have LCRcrossover frequencies of 575 Hz and 5, 000 Hz. Thespeaker's impedance ranges from 2.7 – 4.9 ohms, and the speaker isapproximately 0.7% efficient, meaning that an amplifier capable of at least 25 watts-per-channel into 4 ohms is the minimum suitable power. The AR-3a physical dimensions are 14” x 25” x11-3/8.” The AR-3a’s net weight, each, unboxed, is 54 lbs., and in the double shipping carton 64 lbs gross. ©ARHPGDevelopment 1999-2019 USPTO All Rights Reserved- COPYRIGHT NOTICE -
All content seen here, including HTML coding, photos, artwork and text contentis copyright protected as intellectual property and may not be used withoutwritten permission from its owner.
