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Fortura 10 worth fixing?

GearHead454

GearHead454

Still Lost
Hey,
I came into possession of a pair of clapped out Fortura 10 speakers. They have air motion tweeters on top and trashed woofers. Crossovers came in a box and the speakers are not wired currently. Obviously I have never tried to run these as there is a bunch of work required just to test them.

The question I have is: are these worth fooling around with or should I pull the tweeters and save them for a future build? I have a day job and a few other speaker projects in line so these Forturas either need to move up the project list or I should get rid of them.

Thanks
fortura 10.jpg
 
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Those look cool! Crossovers in a box, does that mean they are external or are they supposed to go in the cabinets? Do you have grills? If it were me, I would definitely fix them just to see what they sound like.
 
Wow, I've never seen those before. I'd would absolutely get those up and running.
 
Thanks for the encouraging input everyone. Crossovers are mounted to terminal plate and were removed by a previous owner (see attached image). There are no grills and I think there should be a top piece of wood like the ESS AMT 1 towers have.fortura badge.jpg
fortura xover.jpg
 
Wow, thanks for the info. I am surprised that anyone has every seen/heard of these Forturas. I actually have a working pair of ESS AMT-1 towers (hooked up to a vintage Marantz receiver) so I know and really do like the upper end as many seem to agree on with the Heil tweeter. The Bass from the 10" woofer is ok also. I know many think that a newer model woofer would be better combined with the Heil. If I am to get these going I now need to hook stuff up and see what works and what doesn't. As I said the crossovers were in a box when I got them so I am not sure which wires go to which speakers. Two wires have female ends that match the woofer male tabs; the other two wires with bare ends should be for the tweeter I guess. Any suggestions on how to safely test these drivers on the workbench before I refoam etc. etc. would be appreciated. Looks like this project is moving up on the list. Attached are images of crossovers. And yes there is a bunch of cotton glued inside the box.20160508_172948_resized.jpg 20160508_173029_resized.jpg

Thanks
 
Hey thanks thatToolguy for the detailed info. You are correct there is a capacitor hidden in there (see attached image). The woofers still have the red dots so that's great. I also attached images of Heil's where I can now see the different colored wires they used. I hope to hook things up this weekend.20160509_195302_resized.jpg 20160509_195337_resized.jpg 20160509_195341_resized.jpg
 
Got distracted last week with work.....prior to ordering new caps and foams I thought I should check things a little. I checked impedance of the existing drivers with my little multi-meter and found the following:
woofers are both at 3.6 ohm
pink/purple (older) tweeter is at 6.2 ohm
purple/blue (newer) tweeter is at 4.6 ohm

Is there a problem here?
Is there anything else I can/should check before ordering parts?

Thanks
 
Congratulations on the find! I have a pair of Fortura 8's that I haven't had time to play with, so I'll be following this thread closely. Can't contribute much other than to reinforce that the lower-cost Fortura's, when they were being produced, were rated as performing at the same level of the more expensive ESS products.
 
Yeah, All working now! Probably first time these Forturas have played in a couple of decades. Thanks thatToolguy! Without your help I would have gotten rid of these. Really glad I did not. They sound amazing. Cabinets are not much to look at but they fill up my shop with great sound. I removed the cotton from the cabinets as you suggested also. Next to the Fortura is an ESS AMT-4 that I refoamed today also. The Fortura with new caps sounds better than the AMT-4 which is all original except for foam. I'd like to recap the AMT-4s next. I also think I need to put a larger receiver in my shop now also. I tested these with an old Luxman R-3055 and I am not sure it is up to the task.

20160528_162638.jpg
 
Thanks again for keeping me on track through the repair and thanks for your thoughts on finishing the cabinets. I will probably clean them up and paint them as you recommend although the wood (vinyl veneer) is peeling at places and may not be salvageable. It may be better to just peel off the veneer vinyl and paint the whole thing black. Thoughts? I am not sure what you meant by "put the edge back on the baffle around the woofer". Is that the fiberboard ring that I have seen over the metal frame of woofers? If that's what I need I have to find one or make one up as these speakers didn't have those rings when I got them. Any more info on the woofer baffle would be appreciated. As I said I am currently using a Luxman R-3055 receiver in the shop to test these speakers which is 55 watts/channel. All my larger sources are in the house. Do you think that 55 wpc is borderline? I have it turned about halfway up to get substantial volume as the shop is pretty large. I was also using the Luxman on the AMT-4 but I am not going to do that anymore as those speakers are rated at 4 ohms. The Fortura 10s are rated at 6 ohms so I thought that Luxman receiver might be ok but now I am wondering. Should I really try to get up to 85 watts or so to be on the safe side?
 
Hey, I really appreciate your AMT 1 pictures. What a beautiful final product! Of course I found your rebuild thread for the AMT 1 and that was great. I am going to work on the Fortura cabinets a bit even if they stay part of my shop sound system. It will be a good learning experience in cabinet restoration if nothing else. I picked up the bondo, paint and 320 sandpaper today. I am thinking about doing them with white grill cloths on a masonite frame ( I will spray the Masonite white first also). How should the tweeter area be handled? Should there be a wood top on the ledge above the tweeter like the AMT 1 towers have or should the top be grill cloth on a frame like the AMT-4 has? Any thoughts would be appreciated.
 
Hi Sean
Happy Holidays.

The Fortura 10s are probably the speakers I use the most. This is because they are in my shop. So it's not "serious" listening but it is quality listening. This is pretty funny because I only paid $50 USD for them. I have a bunch of other (more expensive) speakers that I wouldn't let sit in the shop so they go unused while the Forturas pound the tunes away.

I got them running with the help of an AK member who is no longer here. I built grill covers for them but never refinished the cabinets because they are in the shop. I drive them with a Marantz 2325 receiver. They do seem to like a bit of power.

I have not had to change the diaphragm on the AMTs. They seem to be working fine. I have not noticed the tweeters reducing at volume but I don't listen that loud. Although the shop is large (1,400 square feet with 14 foot ceilings) so by normal home standards I definitely have them running louder than I would if they were in the house.

Early this year I started having an intermittent problem with one of them that I tracked down top the circuit breaker mounted on the crossover. I just eliminated the circuit breaker and replaced it with a conventional fuse. Problem solved. While I was working on them I had other speakers going in the shop and really noticed that the Forturas were much better.

I will post this to the original thread in case anyone else has these very unusual speakers. I will post the current pictures there also.

How many pairs of them do you have? What do you drive them with? Are the more common in the land down under than here?

Craig

PXL_20201226_232005778.jpg PXL_20201226_232027990.jpg
 
Great pix of the Fortura 10s! Brings back memories. Bought a pair new in July '76. Chose those because Heil AMTs produced such amazingly crisp highs. cabinets originally are open above the AMTs and in front. A piece of grooved black foam, held in place by velcro, covered the cabinet top and front. That chunk of lumber over the AMT in the photo is definitely not original equipment. I cut a couple pieces of safety glass instead, sized to rest on the top edges of the cabinet sides. Seemed to help the sound.

Both AMTs in my speakers died in 1994. At the time they were deemed not worth repairing. Heil AMTs went through a period on the black list due to a manufacturing flaw that caused the pleats to detach from the metal yoke. But I got 18 GREAT years of service from them.
 
DrummerMan said:
Great pix of the Fortura 10s! Brings back memories. Bought a pair new in July '76. Chose those because Heil AMTs produced such amazingly crisp highs. cabinets originally are open above the AMTs and in front. A piece of grooved black foam, held in place by velcro, covered the cabinet top and front. That chunk of lumber over the AMT in the photo is definitely not original equipment. I cut a couple pieces of safety glass instead, sized to rest on the top edges of the cabinet sides. Seemed to help the sound.

Both AMTs in my speakers died in 1994. At the time they were deemed not worth repairing. Heil AMTs went through a period on the black list due to a manufacturing flaw that caused the pleats to detach from the metal yoke. But I got 18 GREAT years of service from them.
Click to expand...

First, welcome to AK. I have been involved with ESS products since I first sold them in 73, although we never sold the Fortura product line. Glad you liked them while you owned them. The company has been in continuous business since that time and is still operating. I assure you, there was never any ESS Heil black list. Diaphragms for your Heils are available and have been for a long time. Too bad it seems you don't have them anymore.
 
I apologize for my imprecision. "Black list" is my short hand for what I was told over & over when I went in a vain search for speakers with AMT tweeters after my Fortura 10s went nonop. AMTs in general (not Fortura in specific) had acquired a bad name in the market due to manufacturing flaws, and speaker manufacturers were shying away from AMTs. That was 1994. Finding no high end units with AMTs, I had to "settle" for a pair of Infinity CS9003. Those were in service till last week. Almost 30 years. Apparently the AMT warts are removed because my new Wharfedales sport excellent sounding, albeit significantly reconfigured, AMTs.
 
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