Acoustic Research

The company that put real bass in a bookshelf

History

Acoustic Research (AR) was founded in Cambridge, Massachusetts in 1954 by Edgar Villchur and Henry Kloss. The company's mission was revolutionary: to build speakers that accurately reproduced the original sound without coloration—a radical departure from the horn-loaded and bass-reflex designs dominant at the time.

Villchur, an audio engineer and educator, had developed the acoustic suspension principle in the early 1950s. This design sealed the woofer in an airtight enclosure, using the trapped air as a restoring force instead of a mechanical spring. The result was deep, accurate bass from a relatively small cabinet—unprecedented in the industry.

The AR-1 (1954) was the world's first acoustic suspension loudspeaker. While expensive ($185—equivalent to over $2,000 today), it achieved bass response below 40Hz from a cabinet of just 1.6 cubic feet. The AR-1 established AR as a serious engineering company and attracted audiophiles seeking accurate sound.

The AR-3 (1958) refined the acoustic suspension design and added a dome midrange and tweeter—another industry first. The AR-3 became the reference standard for accurate sound reproduction and remained in production for over two decades.

The AR-3a (1967) improved upon the AR-3 with better drivers and crossover. It became AR's best-selling model and is still highly sought after today. The company also pioneered the AR-LST (Living Stereo Theater), a four-way speaker designed for consistent sound throughout a room.

Teledyne acquired AR in 1967, and the company changed hands several times over subsequent decades. While original AR speakers are no longer manufactured, the acoustic suspension principle remains fundamental to speaker design.

Key Facts

Legendary Products

AR-1 (1954)

The world's first acoustic suspension loudspeaker. The AR-1 used a 12\" Altec 755A woofer in a sealed enclosure, achieving bass response to 35Hz from a compact cabinet. It proved that deep bass didn't require massive horn-loaded enclosures.

AR-3 (1958)

The speaker that established AR's reputation for accuracy. The AR-3 combined an acoustic suspension 12\" woofer with dome midrange and tweeter—an industry first. It became the reference standard for natural sound reproduction.

AR-3a (1967)

An improved version of the AR-3 with better drivers and an improved crossover network. The AR-3a became AR's most successful model, selling over half a million pairs over its long production run.

AR-LST (1971)

The \"Living Stereo Theater\" was a four-way speaker designed to provide consistent frequency response throughout a room. Using multiple midrange and tweeter drivers, it was ideal for large spaces and professional monitoring.

Sound Signature

AR speakers are characterized by:

• Accuracy - Faithful to the original recording
• Smooth response - No peaks or harshness
• Deep, tight bass - Acoustic suspension advantage
• Wide dispersion - Consistent sound throughout room
• Musicality - Natural, uncolored presentation

Collecting AR

Vintage AR speakers are valued for:

• Historical significance - Changed speaker design forever
• AR-3 and AR-3a - Classic acoustic suspension designs
• AR-LST - Rare and desirable for large rooms
• Original condition - Unmolested examples increasingly rare
• Restoration potential - Simple designs, available parts

Most collectible models:

• AR-3 - The original legend
• AR-3a - Best-selling classic
• AR-LST - Rare and unique
• AR-9 - Late-period flagship

Competitors & Comparisons

AR vs KLH: Henry Kloss founded both; similar acoustic suspension philosophy

AR vs Advent: Similar market positioning; both founded by Kloss

AR vs JBL: Opposite approaches; AR accuracy vs JBL dynamics

Amplifiers

• Carver M1.0t — Carver M1.0t amplifier, known through period ads claiming -110dB S/N and a fanless Magnetic Field design. Little else documented.
• Carver M400 — AR Carver M400 magnetic field power amplifier. 201W/ch into 8 ohms, 0.05% THD. Designed by Bob Carver. Little documented; specs from Audio magazine.
• Pioneer SA-8800 (1979-1981) — Little-documented AR/Pioneer integrated amplifier from 1979–1981. Known from a single period review: 80 W/ch rated, non-switching design.

Audio

• AR-2a (1960–1965) — The AR-2a mates a ten-inch sealed-box woofer to the AR-3's dome super-tweeter — warm, forgiving acoustic-suspension sound that demands careful restoration.
• AR-4x (1966–1973) — Acoustic Research AR-4x (1966–1973): an 8-inch sealed acoustic-suspension bookshelf that reaches 45 Hz, sells for $130–$200 used, and still competes.
• AR-5 — The Acoustic Research AR-5 (1968–1971) delivers AR-3a refinement in a tighter, more balanced package—vintage accuracy with soul.
• AR-7 — Compact acoustic suspension speaker from 1972 offering deep bass in a small shelf-mountable cabinet with wide dispersion tweeters.
• AR-9 — The 1978 Acoustic Research AR-9 redefined high fidelity with its four-way design, twin woofers, and unmatched neutrality—still revered by audiophiles today.

Power Amplifiers

• 200-W — Acoustic Research 200-W power amplifier, 200 W/ch, documented only in two 1990s HiFI-Stereo listings. Limited production, few surviving specs.

Receivers

• SX-3500 (1980-1982) — AR The SX-3500 — an obscure audio model with almost no surviving documentation; the only period clipping in the file refers to the unrelated Pioneer SX-3500.

Speakers

• 11 — Acoustic Research AR-11: the AR-10π's identical twin without the Woofer Environmental Control. Identical drivers, crossover, and accuracy at a lower price.
• 18 — AR 18 bookshelf speaker, circa 1978. Little documented; known from a High Fidelity ad showing ~$70 price alongside the AR 9.
• 21 — The Acoustic Research 21 is an undocumented phantom model — no specs, no price, no production years. If it existed, the paper trail has vanished.
• 29 — Acoustic Research Model 29 appears nowhere in the archive's documentation. The number surfaces only as a 29-inch AR shelf stand (1965) and in the Heathkit AR-29 receiver — neither an AR product.
• 312 — Acoustic Research 312 HO (c. 1997): AR's 97dB-sensitivity High Output flagship floorstander with 30cm woofer, dual 13cm midranges, and Aeroform tweeter.
• 330 — Acoustic Research 330 — a little-documented 3-way acoustic-suspension speaker from the mid-1980s, known only from a single 1986 HiFI-Stereo directory entry.
• 570 — Acoustic Research 570 (c.1990–1992) powered speaker system known from period ads. 5-inch polypropylene woofer, liquid-cooled tweeter.
• AR (1967-1976) — Acoustic Research AR-3a (1967–1976) — 12-inch acoustic suspension speaker with sealed enclosure, 38Hz–20kHz response, and legendary neutrality.
• AR-1 (1954) — Floorstanding loudspeaker with side-firing powered woofer, introduced in two distinct eras: the original 1954 acoustic-suspension pioneer and the…
• AR-12 (1974) — Acoustic Research AR-12 3-way bookshelf speaker from 1974, featuring acoustic suspension design and walnut veneer cabinet.
• AR-18 (1978) — Acoustic Research AR-18 (1978): 2-way sealed bookshelf, 200mm woofer, 32mm fluid-cooled tweeter, 86dB, 8Ω. A neutral studio favorite.
• AR-18BX (1980) — Acoustic Research AR-18BX (1980) — sealed 2-way bookshelf speaker with 8-inch woofer, soft dome tweeter, 52Hz–25kHz response. The affordable AR classic.
• AR-18BXI (1982) — Acoustic Research AR-18BXI bookshelf speaker from 1982, featuring acoustic suspension design, 10-inch woofer, and bi-wire capability.
• AR-19 (1994) — Acoustic Research AR-19 (1994) — a sealed two-way bookshelf speaker from AR's Advanced Development Series, rated 45 Hz–20 kHz with a ferrofluid-cooled dome tweeter.
• AR-1W (1954–1973) — Acoustic Research AR-1W (1954–1973) — the first commercially successful acoustic-suspension woofer, 35 Hz extension from a 14-inch×25-inch×11.5-inch walnut cabinet, 12-inch woofer, first-order crossov…
• AR-3 (1959–1967) — Acoustic Research AR-3 (1959–1967): the sealed acoustic-suspension two-way that made deep bass in a small box possible. 35 Hz–15 kHz, ~86 dB, 8 ohms.
• AR-303a (1994) — Acoustic Research AR-303a (1994) — sealed acoustic suspension three-way with 30 cm woofer, 32Hz–20kHz ±3dB, rosewood veneer, and AR-3a lineage.
• AR-30B — Acoustic Research AR-30B (Teledyne era) — mid-size bookshelf speaker with 254mm woofer, 25mm dome tweeter, 88dB sensitivity, 100W handling. Acoustic suspension design.
• AR-38BXi (2000) — Acoustic Research AR-38BXi — early-2000s BX-series 2-way bass reflex bookshelf with 8-inch woofer and 1-inch dome tweeter. Warm, cheap, refoam before you buy.
• AR-3st — Acoustic Research AR-3st — an obscure separate super-tweeter add-on for the AR-3, documented only in a 1963 HiFI-Stereo listing.
• AR-3t — Little is documented about the Acoustic Research AR-3t, though the AR-3 was introduced in 1959 and was praised by Hirsch-Houck Labs as producing sounds.
• AR-48BX (1993) — Acoustic Research AR-48BX bookshelf speaker from the 1990s BX series, offering balanced sound and solid build at an affordable price.
• AR-4ax (1969) — The Acoustic Research AR-4ax (1969) is a compact acoustic suspension bookshelf speaker with an 8-inch woofer and phenolic ring tweeter.
• AR-58BXI (1988) — High-performance bookshelf speaker from Acoustic Research's Advanced. Development Series, combining classic acoustic suspension principles with modern materials and efficiency.
• AR-8 (1973) — Acoustic Research AR-8 (1973) bookshelf speaker with 8-inch woofer, 87 dB sensitivity, 8 ohm impedance — a compact, accurate vintage speaker for rock and hi-fi enthusiasts.
• AR-8B (1968) — The Acoustic Research AR-8B is a compact bookshelf speaker from the late 1960s, known for its accurate acoustic suspension design and warm.
• AR-90 (1979) — Acoustic Research AR-90 (1979) floor-standing four-way with two 10-inch acoustic-suspension woofers, 23 Hz–30 kHz rating, 4-ohm load dipping to 3.2. Under $600 at launch.
• AR-90 (1979) — Acoustic Research AR-90 (1979) floor-standing four-way speaker — two 10-inch acoustic-suspension woofers, 4-ohm load, under $600 at launch.
• AR-91 (1978) — Acoustic Research AR-91 (1978): dual 12-inch woofers, sealed acoustic suspension, 78 lbs each. A restoration-friendly AR classic worth $300–$600 a pair.
• AR-915 — Acoustic Research AR-915 three-way speakers — a stereo pair with foam-surround woofers, documented mainly through a dedicated refoam kit.
• AR-94S (1980) — Acoustic Research AR-94S (1980) — 48 lb sealed 3-way with 10-inch woofer, dome mid/tweeter, bi-wire posts. AR's final-generation sound.
• AR-98LS — Acoustic Research AR-98LS — a little-documented speaker from 1984, known only from a HiFI-Stereo listing with 28–22kHz response and 91dB efficiency.
• AR-98LSI (1987) — Acoustic Research AR-98LSI (1987) — 39-inch, 62 lb three-way floorstander with 10-inch woofer, 90 dB sensitivity, walnut veneer. Late-era AR collectible.
• AR-9LSI (1993) — Acoustic Research AR-9LSI (1993) — last flagship AR tower, dual 12-inch acoustic suspension woofers, 8-inch mid, 1-inch dome. $800–$1,500 used.
• AR3a (1967–1980) — The Acoustic Research AR3a (1967–1980) paired a sealed 1.7 cu ft acoustic suspension cabinet with dome drivers for 30 Hz bass and a voice you can't forget.
• AR90 — Acoustic Research AR90 (1979): four-way floor-standing tower, twin 10-inch woofers, 4-ohm load, three level switches, under $600 at launch.
• M1 — Acoustic Research M1 two-way acoustic-suspension bookshelf speaker, 6-inch woofer, 3/4-inch dome tweeter, documented in Audio magazine January 1992.
• M6 — Acoustic Research M6 compact two-way acoustic-suspension bookshelf speaker, 6-inch woofer, 3/4-inch soft-dome tweeter, circa 1992.
• research-ar-17 (1978) — Compact bookshelf speaker from Acoustic Research's Advanced Development series, known for neutral sound and acoustic suspension design.
• research-ar-3 (1958–early 1970s) — Acoustic Research AR-3 (1958): Villchur's sealed acoustic-suspension three-way with the first production dome tweeter and midrange. 58 lbs of influential bass.
• research-ar-338 (1975) — 2-way bookshelf speaker with acoustic suspension design from Acoustic Research, likely part of their budget lineup in the 1970s.
• research-ar-3a — Acoustic Research AR-3a — sealed three-way with a 12-inch acoustic suspension woofer, 25-inch tall, sold around $225–$250 by finish. Period documentation only; full specs unverified.
• research-edge-sequel (1988) — Compact bookshelf speaker from Acoustic's EDGE series, offering balanced sound and solid build for budget-focused audiophiles in the late 1980s.
• research-m2 (2012) — Acoustic Research M2 bookshelf speaker with balanced sound and modern revival design. This page has the complete spec table and when it was made.
• research-tsw-100 (1987) — Vintage 2-way bookshelf speaker from Acoustic Research with 100W power handling and classic acoustic design principles. Includes full specifications.
• research-tsw-110 (1987) — Acoustic Research TSW-110 floorstanding speaker from 1987, featuring. 2-way bass reflex design and 10-inch woofer with neutral sound signature.
• research-tsw-310 (1987) — Vintage stereo speaker from Acoustic's TSW series with balanced sound and classic build, produced from 1987 to 1990. Find the complete spec table here.
• research-tsw-410 (1988) — Acoustic Research TSW-410 floorstanding speaker from 1988, featuring a 2-way design with 10-inch woofer and dome tweeter in a sealed enclosure.
• research-tsw-510 (1988) — Vintage 2-way bass reflex speaker from Acoustic Research with 10-inch woofer and dome tweeter, part of the TSW series from the late 1980s.
• research-tsw-610 (1989) — Vintage floor-standing speaker from Acoustic Research's TSW series, featuring acoustic suspension design and accurate sound reproduction.
• research-tsw-710 (1989) — Acoustic Research TSW-710 floor-standing speaker with 12-inch woofer, 91dB sensitivity, and 32Hz–25kHz response — a late-era AR tower built for dynamics and clarity.
• research-tsw-810 (1988) — High-performance vintage loudspeaker from Acoustic Research's TSW series, combining acoustic suspension principles with modern power handling for balanced.
• research-tsw-910 (1989) — High-performance 3-way speaker from Acoustic Research's TSW series, featuring acoustic suspension design and accurate sound reproduction.
• TSW 610 — AR Acoustic TSW 610 floor-standing three-way acoustic-suspension speaker with 12-inch woofer and Tetra-Helix tweeter mount.
• Wharfedale Linton — Obscure AR Wharfedale Linton speaker — almost nothing documented. Period dealer ads from 1972 suggest a £106.00 list price. Specifications unconfirmed.

Turntables

• AR XA — Acoustic Research AR XA manual turntable. Belt-drive, synchronous motor, two-speed (33 & 45 rpm). Documented in HiFI-Stereo 1967-1975. Little else recorded.
• research-the-ar-turntable (1961) — A groundbreaking belt-drive turntable with suspended sub-chassis introduced in 1961, known for low noise and high fidelity performance.
• XA — Acoustic Research XA turntable, manual single-play with integrated tonearm, priced at $129.50 in 1971. Little-documented model from the mid-1960s.
• XB — Acoustic Research XB turntable — the later version of AR's classic belt-drive suspended-chassis design, documented in 1970s period reviews.

Unknown

• 312-HO (1996) — Acoustic Research 312-HO (1996): flagship of AR's High Output series, a 97 dB floorstander with side-firing 12-inch woofer, dual 5.25-inch midranges, and 1-inch foam dome tweeter. $1,199/pair.

Other Models

• 1 — The AR-1, Acoustic Research's first speaker from 1954, introduced the acoustic suspension principle and changed loudspeaker design.
• 10pi — The Acoustic Research AR-10pi blends studio-grade adjustability with the legendary AR sound, offering near-flagship performance in a refined 1970s floorstander.
• 10TT — The AR-10TT (1978) is a refined, user-adjustable evolution of AR's acoustic suspension legacy, prized for its room-adaptive bass control and coherent three-way design.
• 1w — AR 1w loudspeaker, ca. 1955. A lower-priced sibling of the AR-1, available in several wood finishes for $132–$145. Little else is documented.
• 266HO (ca. 1998) — Acoustic Research 266HO (ca. 1998) — a little-documented tall boy floorstanding speaker from AR's HO series. Specs, design, and what the record doesn't show.
• 2a — The AR-2a combines the AR-3's legendary tweeter with the AR-2's compact design, delivering transparent, fatigue-free sound that still impresses today.
• 2ax — The AR-2ax delivers the legendary 'New England sound'—warm, accurate, and effortlessly musical—when properly restored. This page has full specifications.
• 2ax-speakers — The AR-2ax is one of those speakers that shows up again and again in period advertising and industry photographs, even though formal documentation of the
• 3 — The AR-3 redefined audio accuracy with its acoustic suspension woofer and world-first dome tweeter—still revered for its lifelike, uncolored sound.
• 310HO (1997–1998) — Acoustic Research 310HO (1997-98) tall-boy floorstander — 3-way, 4-speaker, 25cm woofer, 95dB sensitivity, ¥180,000/pair. A little-documented late AR HO-series model.
• 312HO — A 3-way, 4-driver floorstanding loudspeaker system designed by Carrie Christie for AR's HO series. Includes the complete spec table and the original manual.
• 3a — The AR-3a redefined speaker neutrality with its acoustic suspension woofer and dome drivers, offering lifelike sound that still impresses today.
• 3a Improved — Acoustic Research 3a Improved (1974–c.1977): the AR-3a updated with a new dome midrange and separate mid/tweeter level switches. 3-way acoustic suspension, 12-inch woofer, 575Hz/4kHz crossover.
• 4 — The AR-4 brought acoustic suspension to the bookshelf, delivering tight, articulate bass in a compact teak cabinet—revolutionary in 1959, still respected today.
• 4x — The Acoustic Research AR-4x (1965–1966) is a classic 2-way bookshelf speaker known for its natural sound, acoustic suspension bass, and enduring build.
• 4XA (Early 1970s) — AR 4XA bookshelf speaker (early 1970s): sealed acoustic suspension, 20cm woofer, 3.8cm dome tweeter, 8Ω, 15W+ RMS. AR's compact classic.
• 5 — The Acoustic Research AR-5 delivers smooth, natural sound through its 3-way dome driver design and acoustic suspension—beloved for vocals and midrange clarity since 1970.
• 58s — AR-58s (1978–1980s) — passive bookshelf speaker with 12-inch square-magnet woofer. Shared driver tech with AR-9L. Find vintage pairs on eBay.
• 6 — The AR-6 delivers deep, controlled bass and smooth highs in a compact bookshelf design—Acoustic Research's underrated mid-tier gem from the 1970s.
• 8BX (mid-1980s) — The Acoustic Research AR-8BX is a mid-1980s sealed two-way bookshelf speaker with a 6.5-inch carbon-loaded woofer and a 25mm liquid-cooled dome tweeter.
• 9 — The Acoustic Research AR-9 (1978–1982) is a towering 4-way floorstander with side-firing woofers, liquid-cooled tweeters.
• 91 — The AR-91 is a 1979 high-current floor speaker with NASA-influenced design, sealed-box bass, and a cult following among vintage audio enthusiasts.
• AR 25 — Acoustic Research AR 25 speaker system — reviewed at $110 in 1980; name also appears in 1966 AR-2 series context. Little else documented.
• AR 25BXI — The AR 25BXI is one of those Acoustic Research models that survives mostly through the parts trade rather than the historical record.
• AR 4XA (1972–1974) — The Acoustic Research AR 4XA (1972–1974) is a sealed 2-way bookshelf speaker with an 8-inch woofer, 32 mm dome tweeter, and 1,600 Hz crossover — an improved AR-4x.
• AR 58B — A 3-way bookshelf speaker introduced in 1980, part of Acoustic Research's 50 series. Find the complete spec table and when it was made here.
• AR 6BX — A bookshelf loudspeaker system with a sealed acoustic suspension enclosure, produced in 1988. Covers full specifications and original documentation.
• AR 925 — A classic 3-way acoustic suspension floor-standing speaker made in the USA. Includes full specifications, original documentation and production years.
• AR EB101 — Acoustic Research EB101 (1977–1982) — 18-lb belt-drive turntable with suspended subchassis and sorbothane damping. A sleeper hit from AR's analog era.
• AR ETL1 — A high-end belt-drive turntable from Acoustic Research’s Reference series, noted for its refined design and rarity. Includes production years.
• AR-10 PIE — Acoustic Research AR-10π (AR-10 Pi) — a rare 1978-era AR three-way with 12-inch acoustic suspension woofer and dome midrange. Scarce on the secondary market.
• AR-10pi — The AR-10pi was AR's final flagship—adjustable voicing, deep sealed-bass, and 3-way clarity in a rare, collectible package.
• AR-10π — The Acoustic Research AR-10π (1977) is a three-way acoustic suspension speaker revered for its neutrality, real wood veneer, and onboard room-tuning controls.
• AR-11 — Acoustic Research AR-11 (1977): the AR-10π's drivers and crossover minus the Woofer Environmental Control, $590/pair, 27Hz–30kHz, AR's most accurate bookshelf.
• AR-11 (1977) — The AR-11 is Acoustic Research's purist take on the AR-10π — same drivers and crossover, no woofer servo, and a sealed 12-inch woofer that still earns its keep.
• AR-14 — Acoustic Research AR-14 (1978–1980): 10-inch acoustic suspension speaker with warm, detailed sound. Foam surrounds fail, but refoam kits available.
• AR-2 — A single-driver, 10-inch acoustic suspension bookshelf speaker that brought high-fidelity bass to a broader market. With current market value.
• AR-38 — The AR-38 packs liquid-cooled power and 3-way clarity into a compact bookshelf design, delivering AR’s legendary neutrality with surprising resilience.
• AR-3a Improved — The AR-3a Improved is the European-tuned version of the classic AR-3a, with a modified crossover to reduce midrange coloration.
• AR-48 — The AR-48S was AR's final high-fidelity statement—3-way clarity, acoustic suspension precision, and a midrange that still stuns decades later.
• AR-48s — Acoustic Research AR-48s, a little-documented early-80s loudspeaker known mainly from a May 1982 High Fidelity test report; impedance measured 6.4 ohms.
• AR-58 — The AR-58 (1981–1984) is a refined, 2.5-way floorstander from AR’s Teledyne era—warm, coherent, and built to last, but often overlooked in vintage circles.
• AR-58s — The Acoustic Research AR-58s (1981–1983) is a heavy, undocumented floor speaker — likely needing refoam, and waiting for a restorer.
• AR-6 — Loudspeaker system introduced in 1971 with acoustic suspension design and an 8-inch woofer for balanced, accurate sound reproduction.
• AR-8s — The AR Acoustic Research AR-8s (1981–1987) delivers punchy bass and clear highs in a compact vintage bookshelf design—reflatable surrounds make restoration easy.
• AR-92 — The Acoustic Research AR-92 (1979–1981) is a 4-ohm, three-way floorstander with user-adjustable crossovers and a sealed acoustic suspension design.
• AR-93 — Floor-standing 3-way acoustic suspension loudspeaker with dual side-firing 8-inch woofers, introduced as part of AR’s High Tech series.
• EB-1 — The AR EB-101 (U.K.) is a 1984 belt-drive turntable with a sprung sub-chassis, JELCO tonearm, and a reputation for responding well to tweaks.
• EB-101 — The AR EB-101 hides a suspended subchassis and refined engineering under humble vinyl-laminate — a sleeper turntable that outperforms its looks.
• EDGE — A compact, weather-resistant bookshelf speaker with a neutral sound profile, part of AR's effort to deliver high fidelity at an affordable price.
• ES-1 — The AR ES-1 turntable delivers quiet, neutral analog performance through a suspended subchassis and precision bearing—solid wood build ages gracefully.
• ETL-1 — The AR ETL-1 is a rare, heavyweight turntable from the 1980s with dual spring suspension and quartz speed control—still competitive today.
• L 100 — AR L100 — 1972 floor-standing 3-way acoustic suspension speaker from Acoustic Research. 12-inch foam woofer, 28 Hz–23 kHz, 8 ohms, 15–100W.
• LIMITED MODEL 3 — A floorstanding 3-way acoustic suspension speaker system released as part of AR's 40th anniversary Limited series. With full specifications.
• LST (1972–1979) — The Acoustic Research LST (1972–1979) is a 90-pound, 9-driver studio monitor with a 12-inch woofer and a six-position spectral energy switch — prized for clinical accuracy.
• LST-2 — The Acoustic Research LST-2 (1972–1979) is a 9-driver, three-way acoustic suspension speaker with a transformer-coupled spectral energy switch and 10-inch woofer.
• M3 — Acoustic Research M3 — a little-documented early-90s two-way bookshelf speaker. Known specs from a Jan 1992 Audio profile: 6-inch woofer.
• M4 — Acoustic Research M4 speaker, early 1990s Holographic Imaging era. Thin documentation; a 1991 HiFI-Stereo test measured a 6-inch bass/midrange with ±1 dB from 65-400 Hz.
• speakers-tsw-510 — Acoustic Research TSW 510: late-1980s 3-way acoustic suspension tower with 10-inch woofer, 6.5-inch mid, and titanium dome tweeter. Thinly documented; foam surrounds are the known weak point.
• TP 1 — AR TP 1 turntable (1982–1985): belt-drive deck with Papst motor, gimbaled tonearm, $275 in 1983. A little-documented entry from the speaker maker.
• TSW-100 — Acoustic Research TSW-100 floor-standing acoustic-suspension speaker from AR's late-1980s TSW series — documented as a series member, but scarce on model-specific specs.
• TSW-110 — Acoustic Research TSW-110 — four-way columnar acoustic-suspension tower with 12-inch woofer, quad mids/tweeters, and six-position balance switching.
• TSW-115P — Acoustic Research TSW-115P powered minimonitor — 16 W/ch active, 4-inch woofer, shielded titanium tweeter, 50 Hz from 0.12 cu ft. $400/pair in 1988.
• TSW-410 — Acoustic Research TSW-410 — a 90-lb acoustic-suspension tower with a 19-inch woofer, four mids, four tweeters, and a fuse that caps long-term input at 23W.
• TSW-710 — Acoustic Research TSW-710 — a 90 lb wall-loading AR floorstander whose surviving manual describes LST-style switching, four tweeters, and a 180 W short-term rating.
• TSW-810 — Acoustic Research TSW-810 — flagship floor-standing columnar with dual woofers on two planes. Production years, price, and specs largely undocumented.
• TSW-910 — Acoustic Research TSW-910 four-way floor-standing acoustic-suspension speaker, $800/pr in 1989, 89 dB, 6 ohms.
• Turntable — The 1984 AR The Turntable revived a legend with superb isolation and elegant walnut styling, but its aging motor demands careful buying.
• XB-1 — The AR XB-1 turntable combines broadcast-grade specs with simple, stable design—still a standout performer decades later.
• XB91 — The AR XB91 turntable, released in 1972, paired a suspended subchassis design with a factory-installed Shure M91ED cartridge for exceptional mid-tier analog performance.