A pair of AR-7 speakers. Serial numbers 12227 and 12234. Excellent cosmetic condition with slightest of scratches to cases. Grills have age related wear as can be seen in photos. Date to the mid-1970s. Amazing to have the original box included. These are vintage, used items. We mark all of our items using an invisible technique. This is for security and later clarification if needed. Collection is very welcome. Acoustic Research AR-7 Speaker MOST “bookshelf” speakers are comparable in size and weight to a set of encyclopedias, and they must therefore be supported by correspondingly rugged shelves. In contrast, the new Acoustic Research AR-7 would be quite at home on a shelf of paperbacks. It measures 153/4 inches wide x 93/4 inches high x 61f4 inches deep, and weighs a mere II pounds. The walnut enclosure can also be hung directly on a wall, using picture hooks and the hardware furnished with the speakers. The AR-7 is a two-way system, consisting of a widedispersion, ll/Z-inch tweeter (essentially the same as that used in the AR-6) and a newly designed 8-inch acousticsuspension woofer. The crossover frequency is 2,000 Hz, and a two-position switch in the rear of the unit provides a choice of two tweeter levels, identified as FLAT and NORM. The system impedance is 8 ohms, and the moderately low efficiency requires an amplifier capable of at least 15 watts continuous output. The AR-Ts frequency response was measured in a “normal” reverberant environment that integrated the total energy output of the system. With the tweeter-level control set to FLAT, the measured curve was among. The flattest we have chartedwithin ±2 dB from 65 to 15,000 Hz. In the NORM position, the response went out as far as the flat curve, but had about 2-dB less energy in the area above 3,000 Hz. The output fell below 60 Hz, but the low-frequency harmonic distortion was quite low, reaching 5 per cent at about 50 Hz, using either a IO-watt drive level, or maintaining a constant 90-dB SPL (sound-pressure level) at a distance of three feet from the speaker. At lower frequencies (as could be inferred from the rapid decrease in output), the constant-output condition produced more distortion than the constant-ddve test. We would judge the effective lower limit of the AR-7 to be about 40 to 213 Hz- which is a very respectable figure for a speaker system of its size. The impedance ranged between 5 and 10 ohms at most frequencies, reaching its maximum of just over 10 ohms at the bass resonance of 70 Hz. The tone-burst response was on a par with that of the other AR speakers we nave tsted-ab6ut as close to ideal as can be measured in a':Iive environment. Ihe effiCiency, though low, was’slightly higher than that of the top-of-the-line AR speakers such as the AR-3a or AR-LST. A drive level of 3.5 volts at mid-frequencies (about 1.5 watts) was needed to produce a 90-dB SPL. The measured characteristics of the AR-7 were so outstanding that we were not surprIsed at Its excellent performance using our simulated live-vs. The only audible difference be’tween our original program and its reproduction through the AR-7 set to FLAT was a very slight dulling of the extreme highs above 10,000 Hz. Even though the AR-7 tweeter has very fine dispersion by contemporary standards, it was not Quite the equal of the dome radiators u’ie.. D in the more expensive AR speakers. The item “Acoustic Research AR-7′ Speakers. Inc. Original Box. 1970s. V. Rare” is in sale since Wednesday, March 4, 2020. This item is in the category “Sound & Vision\Home Audio & HiFi Separates\Speakers & Subwoofers”. The seller is “landl2016″ and is located in bexleyheath. This item can be shipped to United Kingdom, Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Australia, United States, Bahrain, Canada, Japan, New Zealand, China, Hong Kong, Norway, Indonesia, Malaysia, Mexico, Singapore, South Korea, Switzerland, Taiwan, Thailand, Bangladesh, Bermuda, Brunei darussalam, Guernsey, Gibraltar, Iceland, Jersey, Jordan, Cambodia, Liechtenstein, Sri lanka, Macao, Monaco, Maldives, Oman, Pakistan, United arab emirates, Ukraine, Kuwait, Philippines, Qatar.
- Model: AR-7
- System Configuration: 2.0 Channel
- Brand: Acoustic Research
Incoming search terms:
- https://acousticresearchspeakers net/2020/03/acoustic-research-ar-7-speakers-inc-original-box-1970s-v-rare/