Revisiting the Legendary Acoustic Research AR9 4-Way Loudspeakers

[gene]

In 1978, Teledyne Acoustic Research introduced the AR9 (initially called the “AR-25”), a brand-new, technically advanced four-way loudspeaker system that was a radical departure from the firm’s familiar bookshelf-type loudspeakers—well-known to music lovers and audiophiles for many years. Now, forty-four years later, we revisit the flagship AR9, symbolic of the halcyon years of high-fidelity audio, just as the industry entered the digital age. This speaker was a remarkable achievement in loudspeaker design and came when audio enthusiasm was peaking; a time when audiophiles eagerly awaited each new issue of Stereo Review, High Fidelity or Audio magazine to read new-equipment reviews, admire the “Installation of the Month,” or laugh at Charles Rodrigues’ clever cartoons.

It was indeed a reference standard—used by many manufacturers as a benchmark for their speaker designs. Check out our article on the AR9 to see how it was conceived and why it is considered to be one of the most influential speakers ever designed.

Read: Revisiting the Acoustic Research AR9 4-Way Legendary Loudspeaker

 

[DigitalDawn]

Great article Gene.

Remember the NHT 3.3? I think Kenny used some of the AR9 design on that speaker.

 

[jgs5607]

I had the follow up model, the AR9ls.

Loved that speaker, ultimately taken by foam rot. The changes were moving the woofers to the front, a 12" forward facing driver with a 10" down facing driver that fired into a " bass contour chamber", whatever that really is. The other improvement was mounting the upper midrange and tweeter on a common plate, significantly reducing the center to center spacing which helps with vertical polar response.

Never heard then side by side, so hard to assess which was "better", but my in room response extended to 20Hz easily.

I think one of the things the new design did was perform better when freestanding. Like the Allison speakers, the original AR9 was designed to work up against the wall for best performance.

AR was a great company, I am still using my "The AR Turntable" with Grace 714 unipivot Tonearm today when I pull out the vynil......

 

[kracer]

I have some from around the 2000's

 

[Mikado463]

nice walk down memory lane, thanks Gene !

 

[Trell]

For a moment I thought about Cyberdyne but clearly I was wrong.

 

[eautenre]

I have a pair and a pair if AR90 and "more cowbell" with KEF II .. older Onkyo amps still make them sparkle...4 subs for annoying neighbors.

 

[lovinthehd]

Very good article Mr Tyson....

 

[bjmsam]

What a fascinating history of such an innovative company with its roster of legendary players, legacy of industry influence, and collaborative development of a truly impressive loudspeaker that easily holds it own today. The AR-3a speakers in my parents' living room throughout my childhood were the cornerstone of my early passion for acoustics and now are featured in my own, with terrific sound and furniture-grade cabinets achieving a high WAF. My dream of building a home theater anchored by AR-9 speakers eventually was realized decades later, and thanks to the outstanding documentation that uniquely is available for AR speakers, I even managed to build a center speaker identical to the top section of an AR-9 that is flush-mounted behind the AT screen. Kudos to AR for achieving and Tom for sharing!

 

[jeffca]

If you took this design and updated it with components from today, this would still be a fantastic speaker. I remember this box.

The AR9 reminds me of what Legacy and, in a newer design paradigm, RBH makes now. Fantastically engineered big speakers that offer performance for much less money than their direct competition.

Thanks for the flashback.

 

[kracer]

If you took this design and updated it with components from today, this would still be a fantastic speaker. I remember this box.

The AR9 reminds me of what Legacy and, in a newer design paradigm, RBH makes now. Fantastically engineered big speakers that offer performance for much less money than their direct competition.

Thanks for the flashback.

They did remake it in the early 2000s

 

[colinwalks]

I have loved my pair of AR9s for over 40 years. They started bi-amped with the passive crossovers for the first 10 years before being converted to tri-amped with active crossovers, now using DEQX HDP5. They have always been powered by Yamaha M2 amps, originally two, now 4 of them.
I have tried to upgrade many times but have only recently been able build what I feel is a better sounding system. I still listen to the AR9s and still love their sound.

 

[Pat D]

It would be nice to see some measurements, something like the NRC measurements done by Soundstage, or even your own. Just how good were the AR-9s?
I remember hearing them a long time ago, but I did not find the differences were worth the extra money compared to my old Kef 104s. As well, I would have needed a different amplifier to drive them, which would also cost money. Bryston 4B? I now know that the audition conditions in the store were not very good, and that the more even off axis dispersion of the AR-9 were very significant in a listening room. But I didn't know of Dr. Floyd Toole's research at the NRC very well in those days.

 

[Philnick]

Missing from this article was any mention of the role that the introduction and popularity of separate powered subwoofers played in the decline of this sort of loudspeaker - largely driven by the introduction of Low Frequency Effects (.1) soundtracks in home theater systems.

It was a short step from there to redirecting the low bass from other channels to the subwoofer(s), reducing the need for as much amplifier power and deep bass speaker output from the many more than two main channels - probably a large part of the reason for the scorn of older hifi fans for listening to music with home theater setups.

 

[Philnick]

My first very good longtime stereo was a pair of just-released original (later dubbed "Larger") Advents in 1970 powered by a Dynaco SCA-80 integrated amp assembled from a kit. When I set up my first 5.1 home theater and shopped for the audio part of the setup, I looked for front main speakers that sounded like my thirty-five year-old (and several-times re-foamed) Advents.

Before subs became popular, I built into my SCA-80 a "bottom-octave boost" circuit from a schematic in a magazine. This sort of hack led to a cottage industry of replacing the foam surrounds on Advent woofers shredded by this sort of long-term abuse: "Bring in your old Advent woofers - for us to refoam for someone else - and you can buy someone else's re-foamed woofers."

The hifi sales guy I was asking for speakers that sounded like the Advents thought I was crazy for wanting speakers that had woofers and sounded like my Advents. "Those were junk!" He was pushing what were essentially expensive satellite speakers and a sub.

I bought a set of Paradigm Studio 40s for the front, Studio 20s for the sides, and their center channel speaker that was essentially the 40 in black with its footpads on one of the long sides. In the early two-thousands, Paradigm speakers hadn't yet become stratospherically expensive.

They are still the core of my 7.2.4 theater setup, supplemented by less expensive rears and overheads and a second sub, driven by a Yamaha RX-A3070 and an old Denon AVR-2370CI for the four overheads. The Advents now live in my living room stereo, powered by my old Yamaha RX-A1030 5.1 receiver.

And I play the low bass both from the subs and the mains.

 

[Floyd Toole]

Figure 18.3 (h) in the 3rd edition of my book "Sound Reproduction" shows 0, 30 and 60 deg curves for the AR-9, and it was very well behaved. It got high scores in double-blind listening tests and the anechoic curves show why: flattish on-axis response, uniform flattish off-axis behavior - both characteristics that were lacking in many (most?) loudspeakers of the time. The extended bass and optimized room coupling helped - this is shown in Figure 9.12 which includes in-room measurements. Chapter 18 in the book shows anechoic data on many other loudspeakers of the period; it is called "Fifty Years of Progress in Loudspeaker Design".

 

[bjmsam]

It would be nice to see some measurements, something like the NRC measurements done by Soundstage, or even your own. Just how good were the AR-9s?

FWIW, here is how my pair measures in my home theater (depicted above) from the MLP (~15' away, Denon AVR-X4000 volume at -25.0 dB feeding Adcom GFA-585 amplifier, REW level check reporting -25.7 dBFS / 66 dB SPL, RMS average of L+R, Audyssey XT32 set to FLAT with DEQ 10 to help address room challenges). They sound really good to me!

 

[David C.]

I had a pair of AR9 that I purchased new in 1980.They were driven by an Akai PS-200M that I bought at the same time.They sounded amazing in my apartment but couldn’t really push them without getting complaints from neighbour. I think my interest in audio was one of the primary drivers for purchasing a house in 1982. They were the source of much critical listening pleasure and dance party enthusiasm.

I kept them until 2008 when I finally caved to pressure from my wife. They didn’t fit with her sense of room esthetics.

I did keep the Akai system and today the amp powers the left and right speakers of my 7.2.6 home theatre. I had the amp tested by a local repair shop recently and it is still close to the original published specs.

 

[AudioLover73]

I love that you brought attention to the AR9s! My father had a pair of these as I was growing up, so I went out and bought a set of AR9LSs thinking they'd be better (I was heavily influenced by the marketing brochure). They were not (at least not to me). I promptly sold them and bought a set of AR9s. We still have both pairs to this day. I need to set them up and take a proper picture! My dad's are paired with a Sansui G22000.

 

[AudioLover73]

They did remake it in the early 2000s

Yes, but they were very different from the originals. The newer ones were a 3-way design (vs. 4-way) with a single 10" woofer in a ported enclosure. The bass didn't reach as low as the originals with the two 12" woofers. The original AR9 was all about acoustic suspension, with quality bass like none other, reaching down to 18Hz and below.