Your Favorite Vintage Sealed Box Bookshelf Speaker?

Not sure why I like these so much, paper cone tweeter and all, but I have put them up against a bunch of small speakers over the years and kept these.

I have had these for about 30 years.

Synergistics.

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Rob
 
Roll off is a somewhat complicated technical issue, isn't it? I wasn't able to grasp too much of this article algebraically, although I do understand the basic concept:

https://en.m.wikipedia.org/wiki/Roll-off?wprov=sfti1


There's nothing wrong with the AR TSW series. Great speakers, from the models I've heard; TSW 210's daily at work, and 410's that I used to own.

The main deterrent, concerning the TSW's, is their voicing. Most long time Acoustic Research fans love the original AR laid-back, rolled-off treble balance. Non-fatiguing and easy on the ears. Easy to listen to, all day, a more natural balance. Which is nice, if you like a rolled-off balance? I don't. And the TSW's didn't sound rolled-off either, compared to the Classic AR's. So, they weren't well liked when released.

As to favorite vintage sealed boxes, again AR. My AR90's and my newly acquired AR58s speakers. Both well balanced, not rolled-off. Great bass and imaging. Easy to place. My new AR58s speakers are awesome so far, a 12" 3-way, with the 12" woofer, 1.5" dome mid, and a 3/4" tweeter. Very dynamic speaker. Maybe more so than my 90's. Usually cheap too, as most AR Fan's are looking for AR-3's and AR-3a's, and paying $1000 more than I paid for my 58s's, when they're basically the same speaker. Though the 58's do have that more modern voicing. Any of AR "Vertical Series"would be great to own. AR9, AR90, AR91, AR92, and the AR58s all share the same dome mids and tweeters. Except the AR92 has a 10" woofer. And I guess the 58's and 92's could qualify as bookshelves? They do to me!
 
Roll off is a somewhat complicated technical issue, isn't it? I wasn't able to grasp too much of this article algebraically, although I do understand the basic concept:

https://en.m.wikipedia.org/wiki/Roll-off?wprov=sfti1

Roll off, as it applies to the AR-3 or AR-3a, basically references the fact that these speakers have a deliberately designed frequency response. In the case of these speakers, the level of each driver, outputs at a lower level that the previous driver, as the speaker increases in frequency. More bass than mids, and more mids than treble. Many listeners feel that this declining response sounds more natural and musical, than a speaker with flat response. As I stated earlier, less fatiguing than a flat speaker. Here's a response graph, showing the roll off.

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Infinity Infinitesimal .2 - just amazing little vintage speakers , sealed enclosure, with a tiny Watkins with dual voice coil, cast iron cabinet, EMIT tweeter...I drove them with a Parasound 100wpc amp and was very pleasantly surprised :)
 
Infinity Infinitesimal .2 - just amazing little vintage speakers , sealed enclosure, with a tiny Watkins with dual voice coil, cast iron cabinet, EMIT tweeter...I drove them with a Parasound 100wpc amp and was very pleasantly surprised :)
I just picked up a pair of Visonik Davids that appear to be about the same tiny size. I haven't had a chance to listen yet, but I've read very good things.
 
Anyone mentioned Infinity Reference Studio Monitors?
They were touted as "bookshelf" speakers when produced though they are bigger than what is considered modern day bookshelf speakers.
Nice speakers,classic Infinitys with no unobtanium drivers should replacements be needed.
 
A friend had lent me a pair of Linn Sara 9s for the past 3 years, and recently took them back. They were gorgeous-sounding. My Tannoy 609s come close, but they don't quite have the same deep, attractively seductive bass and low midrange.

And I have still held on to a pair of ADC 303AX two ways, paper cones and black goop and all, even though they rarely get played (if I would just put some decent connectors on them, I imagine I would play them much more often).
 
I have a "new" pair of bookshelf acoustic suspension speakers.
An original 1962 pair of AR-2a cabinets.
Parts Express TC-1028 woofers.
Parts Express GRS phenolic ring tweeters.
Used the original 1.18 (ish) choke with the woofers
Used simple 6db/octave 15uf oil filled cap for the tweeters
Woofer / phenolic tweet rolloff / rollup at about 1300 hz
Kept the original AR dome in place for super tweeter duty.
Put the grille cloths back in place.
DANG! they sound suspiciously like I remember a whole lot of late 1960's / early 1970's speakers sounded.
The purists would say it's heresy to stuff an AR box in said fashion, but uhhhhh... the ears give two thumbs up!
 
Only Heresy if you trashed the original drivers. If they weren't present or were badly damaged then it is utility.
There were multiple reasons for the Frankenboxing.
There are a few AR 1st generation boxes making the rotation throughout the house.
The 2a's were being used in the family room for entertainment center duty.
The gut thumping extended bass of the action film genre proved to be more than one of the 55 year old woofer cone / VC / spider assemblies could take and the poor old cast basket driver sailed into the sunset.
While awaiting a driver of suitably similar era, a pair of KLH 6 were called up into service.
The Boss, whose auditory judgement shall never be impugned, noted that the KLH did not excel at movie magic bass.
Just about this time, I had a pair of the Parts Express TC-1028 put in my hands.
I subsequently noticed that Vintage-AR on the auction site was carrying these drivers and had found that they were eminently suitable replacements for the AR-2ax woofers.
He also carried the adapter rings to fit these slightly smaller baskets to the openings for the original cast basket drivers.
I acquired the adapter rings and installed them.
Thumbs up from the Boss!
But then, another drop of critical rain fell on the poor 2a parade.
The cone midranges were astutely described as being less present than the KLH, which now had been returned to duty in the workroom.
At that point I became aware that the Parts Express GRS phenolic ring tweeters were being given approval on various fronts as being eminently suitable as replacements in kind for the AR-4X tweeters.
At one point, these were supposedly also installed in the AR-2x toward the end of it's run.
So, I sez, let's cobble it all together and see what gives.
I put the signal generator in service with an SM-57 on axis and found that the inductor in the cabinet with this woofer began to roll off significantly at about 1300 hz.
The phenolic ring tweeter was resonant at about 1,050 hz.
I used a 15uf oil filled cap for a 6db / octave slope.
The original AR phenolic dome super tweeter crosses over at about 7,000 hz and is a little lacking in the 10K+ range but adds a spike at 7500 when in combo with the phenolic ring tweeter.
Final thing I'll attempt is to install one of the HiVi AR3a tweeter replacements and cross it over at 6,000 and add an inductor to roll off the phenolic ring tweeter at 6000.
If that is a failure, I can return it to any of the various stages of modification.
OR.... If I find a good cast frame 2a woofer I can just return it all to original!


 
My two favorites so far are the ADC-303AX and the Boston Acoustics A60. Also a big nod to the Siemens RL-171, but those are pretty rare. I didn't like the Acoustic Research RedBox IIs (updated AR18) at all. One listen comparing them to the Boston Acoustics A60s, and the ARs went on craigslist. (Also, ARs will need eventual refoaming, and the BAs have rubber surrounds, if that matters to you).

Charles.
 
LS-3/5a for a conventional small speaker

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JR-149 for an unconventional small speaker

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These are the only "cone in a box" speakers that come close to my double 9s in sound stage and presence. Not quite there but close.
 
Before discovering FR SD HE speakers I had a pair of these Aerials which at 84 dbs required huge power. I think they were designed by the same guy that did ADS.

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Technically a sat/sub combo, but the original Cambridge Soundworks Ensemble are fantastic speakers. They fly under the radar, but these and the CS Tower I were Henry Kloss' last development effort, I believe, before he passed away.

I bought a new set of the Ensembles in '89 and did a head to head comparison over the weekend. Back then, they had a 30 day, no questions return policy. They stayed, others went back to the store. They are silky smooth and the sats are easily put where needed while the subs can be "hidden" behind furniture, etc. All sealed, not boomy at all. They can be found rather cheaply these days, but will need a restore. If interested, Bostown has posted some great in-depth reviews/comments/history on them that is well worth the read.

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These old infinitys make great bookshelves.IMG_0605.JPG
Sorry, had to add that. My vote would go to Infinitesimal 0.1 or 0.2 as they can actually go on a bookshelf and still sound good.
 
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