Rectilinear III's finally done.

[Moon_Man]

Isaac - I wiped down each recoat about 15-30 minutes after application. I never just let it sit. The finish would look great, and feel smooth and dry shortly after application and wiping, but months later it would benefit from a new coating. I also would buff the finish with 3M 0000 pads under a random orbital sander.

Remember these are 52 year old speakers and nothing looks to have been done to the cabinets in all that time.

 

[infullview]

Beautiful! I've never had any experience with Rectilinear, how do they sound? How much bass do they produce? Usable frequency response range?

 

[Snade]

Beautiful! I've never had any experience with Rectilinear, how do they sound? How much bass do they produce? Usable frequency response range?

I have a later version of the Rectilinear III Highboy from the early 70's. They slightly modified the crossover and used different 12" woofers in the early 70's compared to the late 60's version.

I would compare the sound to the AR3a - a full range speaker that goes low. The Highboys are ported, so it is a different design. I find them to have a very pleasing low-end from a quality CTS woofer and a full midrange from the wizzer-cone midrange. The high-end is probably more detailed than the AR3a. They do not image like modern speakers. They play big for rock or classical music. If you forced me only to have one set of speakers that I would never tire of, I might pick the Rectilinear III.

Although the design uses two sets of tweeters, the crossover is a three way design. I read from a famous speaker designer back in the day (who did not work on the Highboy) that drivers scattered all over the baffle should not work, but on the Rectilinear III, it does.

The only thing I did to mine was to recap them. That made a noticeable improvement in clarity.

Just my two cents.

Snade

 

[Snade]

Last note, some people find the Rectilinear III low-end to be a bit boomy. The speakers have a built in, low stand at the bottom, but some owners have placed them on a one or two inch short stand to get them slightly off the floor and many favorable responses to that. It also depends on your flooring and room acoustics regarding a short stand or no stand.

Snade

 

[Moon_Man]

Agree with Snade. If there is one shortcoming with the R III's it is the lack of imaging. There is no mystery as to where the sound is coming from with Highboys.

 

[gopenope]

Hello from new member. I have both the 1968 older version and the 1972 newer ones. The old version with single pot and square tweeters is way better. They image cleanly, with superb focus and detail, and the bass is more accurate. I sit about 7 feet in front of them on a low beach chair. They can blast rock ( I like Linda Ronstadt) or deliver full-bodied textured classical music (Bach Cello Suites, Karajan La Boheme). Bass definition and overall clarity is greatly improved by decoupling the cabinets from the floor - mine are on Townshend Podiums tuned for the weight of the cabinets. Unfortunately the Podiums cost about $2K, but the overall package is better than anything I have heard after owning over 30 different speakers since 1970. Amps: McIntosh MC225 and Miyajima 2010 OTL's ($18K). If you think these speakers aren't still the state of the art you should hear them with this level of amplification. Cartridge: Miyajima Madake, Preamp: Miyajima Wo-1.

 

[kirk57]

Agree with Snade. If there is one shortcoming with the R III's it is the lack of imaging. There is no mystery as to where the sound is coming from with Highboys.

My guess is they would image better if the listening position was further away, allowing the drivers to blend a bit.
I’ve mirror imaged mine; easily done since the baffle board unscrews. This helps imaging but they aren’t ever going to be imaging champs due to driver placement. But they get *tonality* of music so very right, that I really don’t care all that much.

I agree with Snade that I’d pick them as my favorite vintage speaker, and maybe my favorite speaker, period.

 

[BillEpstein]

It's been over 4 years since I first removed the grills, but my 1968 Highboys are finally done. Granted, most of those 4 years they sat while other projects took priority, but they are done nonetheless. Sanded out the water stains and scratches, put on the walnut stain and danish oil (6 coats), then recapped. Left them on the workshop system to burn in the caps for a year, then applied another 2 coats of danish oil (this really evened out the finish). Finally did the grills, (well, one so far) and voila. Almost sad that it's over.

View attachment 1796904 View attachment 1796905 View attachment 1796906 View attachment 1796907

Lovely workmanship!

Back in the Sixties, whenever I looked at an Allied Catalog I always drooled over those the most. A perfectly balanced design.

 

[quiet]

I don't think the bass is boomy but the floor reinforcement can take the snap out of some instruments. Using them upside down tames the problem. Do try it before you boohoo.
As does putting them in the bookshelf. I doubt anyone will even consider that. But it is the best bookshelf speaker I got.

 

[gopenope]

Re: Bass - The main thing IMO is to decouple them from the floor without elevating them much more than an inch or two. Makes the bass well-defined and "fast", as well as cleaning up the midrange. Otherwise they can sound muddy and boomy. Do not use spikes, but compliant materials that allow the cabinet to move and vibrate naturally without transmitting any energy to the floor. They are much easier to get satisfying bass from than most other designs, but to hear their deepest bottom end room placement and treatment is necessary. They have output into the 20's (Saint-Saens' Organ Symphony, Fremaux on EMI) if you do that. Most of all, they are honest and neutral. If you really want to hear what your electronics, cables, tubes, and recordings sound like without speaker artifacts getting in the way, the Recs are like objective test instruments.

 

[Moon_Man]

So the thought is to elevate them beyond the 2" or so riser that is already built in?

 

[gopenope]

Hi Moon, the idea is not to elevate much because if the woofer is too high off the floor the natural floor reflection that reinforces bass will be lost. The goal is to decouple the cabinet from the floor so that the cabinet vibrates freely - ideally if you cannot feel any vibration of the floor right next to the speaker the decoupling is adequate. IsoAcoustics does this with their subwoofer and speaker stands, but IMO the risers are too high. Look up the website for Townshend Speaker Podiums (for the Rec's it's Size 3, specific springs to match cabinet weight) to review the theory behind this maneuver. The Podiums use tuned spring-loaded feet just an inch high, which are also adjustable to level the speaker. There is no loss of bass or impact - the Recs deliver that satisfying punch or bass "sock it to you" just as well , it just gets faster and better defined in pitch and timbre. I paid 4 times more for the Podiums that I did for the speakers. LOL

 

[Freds.Bands]

Mine is likely the 1972 version. I have them on a carpeted floor about 10 feet apart and listen about 12 feet away. One is about 7-8 feet from a corner and the other is close to the middle. I have not recapped them yet.
On well-recorded material thr4 sound stage is maybe 2-3 feet wider than the location, but instruments move around due to the old caps. I have a recording of the Great Gate of Kiev (Mussorgsky) where the Rects reproduce a huge sounding bass drum, not boomy, just stomach-churning bass. Also baritone singers do not sound chesty and generally bass is there when it's supposed to be and else it's not there. As a brass instrument (amateur) musician, I look for natural sound, not souped-up, glitzy sound. I am satisfied. I am not as satisfied with my DQ-10s.

 

[Goggle1824]

I’ve often wondered IF imaging could be developed by / improved upon by doing some new / trial baffles that vertically align all of the drivers. I plainly don’t know anywhere enough about all of the various aspects involved with this, which one reason I haven’t ventured down that path as of yet.

 

[Moon_Man]

I have a recording of the Great Gate of Kiev (Mussorgsky) where the Rects reproduce a huge sounding bass drum, not boomy, just stomach-churning bass.

I have several versions of Pictures at an Exhibition but have not run any of them through the Rects. Sounds like a good idea. I will have to try that.

 

[jbailey930]

I’ve often wondered IF imaging could be developed by / improved upon by doing some new / trial baffles that vertically align all of the drivers. I plainly don’t know anywhere enough about all of the various aspects involved with this, which one reason I haven’t ventured down that path as of yet.

Checking back in on this thread as a former Highboy owner...I had great imaging and soundstage with my setup. I had them 3+ feet from back wall and 30inches from sides with about 7 feet between each speaker. I do also have homemade 4' x 2' rock wool panels through first reflection points and behind. Try spacing and placement to make them disappear.

 

[Ruben Acosta]

Checking back in on this thread as a former Highboy owner...I had great imaging and soundstage with my setup. I had them 3+ feet from back wall and 30inches from sides with about 7 feet between each speaker. I do also have homemade 4' x 2' rock wool panels through first reflection points and behind. Try spacing and placement to make them disappear.

I know this an older post but I like the idea of raising the speakers so I'll try that. I think my plush carpet is most of the problem. I'm going to start at 2" and listen. Thanks again.

 

[Ruben Acosta]

My best came from removing that old fiberglass and replacing with 1/2" thick upholstery hi density foam glued on with 3M 77 spray adhesive. These really cleaned up the bass and eliminated that booming. I did one and compared their sound and believe me you can tell the difference immediately.

 

[Moon_Man]

...

and replacing with 1/2" thick upholstery hi density foam glued on with 3M 77 spray adhesive

Do you mean like foam for cushions? Back wall or all sides? I reused to original fill with some apprehension.

 

[Ruben Acosta]

...

Do you mean like foam for cushions? Back wall or all sides? I reused to original fill with some apprehension.

You do the same sides, except for battens and bracing. I bought the foam from Amazon, BayTrim .5" x 24" x 82" for $15.99. I ended buying once for each speaker. You'll have enough to add another layer perhaps in the back if you insist but I think one layer is enough. Here are pics.