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Frazier Ceiling Speakers Circa 1967


Flashback67

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Just joined the Klipsch F.U.G. forum at the recommendation of some one on the Audiokarma forum.   My wife and I recently purchased a Mid Century Modern home circa 1967.  Architecturally the home was ahead of it's time, with a big open floor plan, electric drapes, remote lighting controls, and a media room stereo speakers in every room. We would have never been able to afford a home like this built new, but because the neighborhood schools are not the best, the price was right. Sadly though the floor plan did not provide any good locations to position my Klipsch Cornwalls I had owned for 30 years . So I sold them for more than I paid for and started a fund to up grade the homes audio system.

 

 

 

In the home's custom built solid oak media center survived a visually pristine Dual 109 turn table and a Sony 250 reel to reel player. 

 

 My original plan was to just keep the turn table and reel to reel and replace everything else with modern electronics starting with the speakers. At one time I had dreamed of buying a tube amp to power my Cornwalls, but priorities change. The first speakers on the list for replacing were the wall mounted speakers in the media center. Pulling off the grills I was surprised to discover a pair of coaxial 15" EV Wolverine LT- 15 speakers.  I learned how to adjust the "Brightness" knobs and the speakers started to come alive. With a little work on the surrounds and powered by a good amp they should sound great.

After the pleasant surprise discovering the Wolverines I decided to find out what was behind the grills in the 6 other room's 12 ceiling stereo speakers. What I found was both good and bad. The good was instead of finding a simple 6" speaker screwed to a hole in the ceiling I found 12 "small" acoustic suspension Frazier speakers. The "small" speakers measure 12' X 12' X 16', have a 6.5" Frazier woofer, a Frazier horn tweeter, and are constructed of 3/4" high grade plywood (see photos). Very heavy and painted black.  The  bad, the woofer surrounds were literarily gone, and the cones crumbled to the touch. Even worse the woofer is installed from the back and the cabinets must have been installed in the ceiling before the plaster board, so the hole in the ceiling is smaller than the speaker making easy removal impossible without cutting the cabinet.

Now my request for technical help.  I had been searching the web for a potential woofer replacement and had come out empty handed. My searches centered on home stereo woofer replacements and found only high power (100 watt) replacements for modern speakers. Turns out however there is a market out there for low power, high efficiency replacement speakers for vintage portable guitar tube amps! Eminence Speakers manufactures a 20 watt 6.5" woofer with good specs that may be a perfect replacement . Plus it is made in the USA. Check out the Eminence 620H specs a :  https://www.eminence.com/pdf/620H.pdf

Can any of the F.U.G gurus take a look at the specs for the Eminence 620H and give me guidance if the 620H would make a good replacement for the Frazier woofer? The best I can determine the Frazier horn tweeter gets flat between 5K and 20K. The installed capacitor is 3.0 MFD 50 VDC.

Thanks in advance for any help finding a replacement.

 

 

Frazier Tweeter.JPG

Frazier Woofer.JPG

Vintage Ceiling Speaker.JPG

Why Sold Cornwalls.jpg

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Why don't you let someone like Simplyspeakers re-foam the surrounds if that's all that's wrong with them?

 

EDIT, the black font was hard to read but it looks like the cones may be bad too.  I'd still call SS and see if there's anything they could do to bring them back to spec.

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Checked with a couple speaker repair shops.  There is no cross reference of replacement parts to 6.5" Frazier speakers.  If I send them the speaker they will try and match it. But no promises.  If they can repair it the cost is $60 plus shipping.  And I have 12 speakers to repair.  

 

What makes this option even more difficult is since the speakers are installed on the inside of the cabinets, the only way to remove them whole is to either cut up the cabinet or cut up the ceiling.  If I can use a replacement speaker I can cut the old speaker to come out the hole and install the replacement on the outside. 

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Measure the internal volume of the box and call Eminence and ask.  Estimate the volume of the horn and driver using simple figures like triangles, half-spheres or the average of the areas at each end times the length.  The results will be accurate enough.  Subtract the horn volume from the box volume.  Eminence has a help line that is very good at answering these questions.  A change in woofer, with different electro-mechanical characteristics and response curve will likely need a new crossover.  That's easy enough with a little info and Xover Pro, even via long distance. 

 

Be willing to look at 8" woofers, too, to make the box work.  The worst case would be getting in the attic with a sawsall and cutting off the "back" of the box for access.  Repair with glue and screws should be possible.  

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Thanks John,

I already have calculated the box internal volume and calculated the crossover frequency for the current capacitor, 6625 Hz at 8 ohm.  I hadn't taken a meter to measure the speakers resistance yet, but based on the 3.0 MFD capacitor using 4 ohm put the crossover frequency at 12,000 HZ.  So I am guessing I actually have an 8 ohm speaker.  Will check with a meter tonight.  But are Frazier woofers and tweeters of this vintage typically 4 or 8 ohms?

 

Oh, if you look carefully at the photo of our house you can see that the roof is flat.  No attic for access.

 

Had not considered upgrading to 8".  But may be a good idea.  Definitely greater number of options. 

 

 

 

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I didn't realize that roof meant no attic.  A single capacitor for a high pass filter is a very slow roll off, so the calculated crossover may well be very high to protect the tweeter.  I'll bet speakers from the late 60s had all moved to 8 ohms.  An 8 ohm tweeter should show 6 to 7 ohms DC resistance. 

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Thanks John, 

I checked the woofers and they are 8 ohm. 

 

It has been awhile since I have played with audio electronics.  So when I measured the speaker diameter I mistakenly measured the cone, not the outside basket diameter.   In short, I already have 8" speakers.  And the cabinet hole  requires no modification for installation.  Great news since the woofer replacement options are much larger. 

 

Now the the bad news. The tweeter is blown.  And there are at least a couple more. 

 

 Checking the internet I cannot find any diaphragm replacement kits. Are there any available?

 

Next option is I have found some 5 X 7 Frazier replacement tweeter assemblies at a decent price, but the magnetic arrangement is different.  Instead of the tall small diameter alnico style magnet under a plastic cup, it has a short large diameter magnetic and no cup.  The tweeters are marked on the back with:

 

Frazier

F-3x7

N4850-F

114850-F

U.S.PAT.

3,898,393

 

Are these equivalent specs? And what are the differences?

 

Thanks in advance 

 

 

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Have you called Frazier?  You may be own your own because of their age.  This could make a good tweeter, easy-ish crossover.

https://www.parts-express.com/goldwood-gt-1188-piezo-horn-driver-1-3-8-18-tpi--270-082

 

Pick a horn that fits easily enough with a cut-off (minimum) frequency an octave below your crossover (800 Hz horn, 800 hz driver, 1600 hz crossover).

https://www.parts-express.com/cat/horns-waveguides/34?N=21712+4294967118&Ne=10166&No=0&Nrpp=16&Nrs=collection()%2Frecord[endeca%3Amatches(.%2C"P_PortalID"%2C"1")+and+endeca%3Amatches(.%2C"P_Searchable"%2C"1")]&Ns=P_BestPrice|0&PortalID=1

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The architect for our house was Lee Roy Hahnfeld, who studied under Wright. 

 

I contacted Frazier Audio and the told me nicely, go away.  No support or products available for equipment prior to 1987. 

 

My internet searches for adequate replacements has been coming up with more questions than answers. 

 

But by luck or good fortune I may have found the light at the end of the tunnel.  Today I meet with a retired aerospace engineer to buy 10 later model replacement Frazier tweeters.  When I showed the man my old Frazier Alnico tweeter I brought for comparison, he said "Why don't you restore these? I can get the parts."  He is also is pretty confident he can recone my woofers.  His quote is also with in my pain tolerance. 

 

So that hat is now the plan.  Tomorrow I start pulling out speakers.  And I now feel I can remove the old woofers with a much smaller cut in the cabinet face. 

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  • 3 weeks later...

Could use some help from the FUG forum. Back in 2009 Todd Crane posted regarding Frazier ceiling speakers:

 

"The other's were 8 inchers, but one did have a baffle box that fit above the ceiling, so you'd get a little more bass out of it. models #'s: F8-2T-10 with a med duty 8" and a 3" cone tweeter. F8-2C-10 1 med duty 8" driver. F8-3T-10 3 tiered unit ( the other are 2) same stuff as the F8-2T-10, and a sloted f-1200 Modified Helmholtz tuned slot enclosure to fit above all the ceiling speakers. ( the same that we used for all our home speakers."

 

Can Todd Crane or anyone else give me more information on these 8" ceiling speakers?  Especially outside dimensions and where the port is located. 

 

Installed in my ceiling there appears to be two different types of cabinets.  One is approximately 14.5" deep and the other is 12.5" deep.  Both are about 11.5" wide.  No other dimensions are available without cutting into the ceiling.  The builder may have covered over the port with plaster board on some of the speakers. 

 

Thanks in advance. 

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  • 2 weeks later...

Well it has been a month, so I thought I would provide an update on the Frazier home sound system project. 

All the drivers are out of the cabinets and the new diaphragms and re cone kits are in. The fellow rebuilding the drivers is picking them up today. 

Pulling the drivers from the cabinets yielded a few surprises. There are actually three different models of speaker cabinets used in the home's installation.

Outside there are four units I have yet to disassemble. They have an 8" woofer and a 3" diameter cone tweeter. Strangely the cones are still intact even after being outside for 50 years. Must not be normal paper cones.  

Inside there are six sealed cabinet design speakers as shown in the attached drawing I made.  

Finally in the houses two bedrooms there are four ported cabinet speakers. These speakers are the same dimensions as the sealed cabinets except for being a inch deeper. The two slotted ports don't exit the front of the speakers however, they exit the top and bottom. This means they exit into the ceiling joists. At first I thought that the drywall had been installed over the port. But probing with some stiff wire revealed they exited into the ceiling.  

I finally found the answer rereading the old Todd Crane post. It seems the ported model came in two parts, the speaker cabinet and a port kit that fit on top. They didn't install the port kit and left the opening in covered. My plan is to cover the ports and make the cabinets sealed. 

One final surprise was that in one of the cabinets a 4" X 10" tweeter horn was used instead of a 3" X 7" (see photo). 

This cabinet was a bear to remove the drivers from. All the others had the tweeters held in by front removable screws. The large tweeter was fastened in from the back. With the small tweeter removed I could reach in to remove the woofer fasteners. With the large tweeter I need to work through the woofer basket holes.

I will be trading the large tweeter for a small one to install with an adapter plate I will fabricate. 

More in a couple weeks.

 

IMG_0846.PNG

IMG_0845.JPG

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