Today i purchased a pair of good old Heco Superior 940 
I listened to them before the purchase and they sounded great
Whlie driving them home in my car i heard a weird noise coming from the loudspeakers.
It sounded like something dropped inside one of the boxes.
When i carried them from the car inside the house the exact same noise repeated in both cabinets.
It was like a rattle and i imagine something dropped inside the boxes.
Now i'm uncertain what the reason for those noises were and what to do.
Is it possible that the x-o loosend and dropped?
What else could have dropped?
Where should the x-o be located in those cabinets?
Should i simply connect an amp and try the speakers?
Should i remove one woofer (which) and take a look inside?
I listened to them before the purchase and they sounded great
Whlie driving them home in my car i heard a weird noise coming from the loudspeakers.
It sounded like something dropped inside one of the boxes.
When i carried them from the car inside the house the exact same noise repeated in both cabinets.
It was like a rattle and i imagine something dropped inside the boxes.
Now i'm uncertain what the reason for those noises were and what to do.
Is it possible that the x-o loosend and dropped?
What else could have dropped?
Where should the x-o be located in those cabinets?
Should i simply connect an amp and try the speakers?
Should i remove one woofer (which) and take a look inside?
The inductor for the lf driver pulled loose from the crossover board it was hot-glued to. Happens a lot on cheap stuff that endures rough handling unforeseen by the hurried assemblers not permitted to add a ty-wrap, say. You can fix it.
Looks like these were not so cheap. Still, rough handling can cause glued bits to separate.
Looks like these were not so cheap. Still, rough handling can cause glued bits to separate.
Last edited:
That's why i don't want to touch anything if not necessary.
That's the kind of info i was hoping for.
Any idea where the crossover is sitting?
I recently caught my little boy feeding wooden toys into the port of my subwoofer. You'd be surprised at what you might find inside
Shouldn't be too hard to pop the drivers out and fish out whatever might be loose.
Luckily those are closed boxes.
I don´t think it will be hard.
But to me loudspeakers like mine might very well be exhibited in a museum.
I don't want to touch the ribbings or anything else, because replacement parts are hard to get.
I don't even like the screws to look used...
No chance.
I removed the big woofers.
In both chambers i found big round magnets.
It seems those magnets were originally glued to the back of the drivers.
Is there anything wrong with using superglue for the repair?
I guess these are not the actual driver magnets but some bucking magnets that were glued to the back of the pole-plates (these are there to reduce stray magnetic fields, which is not as necessary anymore as it once was because no one uses CRT TVs anymore) . You were saying that they were working when you got them. Am I right ?
Regards
Charles
Regards
Charles
I feared that might be the case!
From the photos I have seen, I do not think these drivers have bucking magnets.
There's lots of discussion on which type of glue is suitable. Some say not to use superglue as it is hygroscopic.
The chosen glue must be a slow setting type to allow you time to re-align the magnet assembly so that the voice coil of the speaker moves up and down freely.
A slow setting epoxy would be a suitable choice in my opinion.
P.S. Under the circumstances, I would check the magnets on all the drivers!
From the photos I have seen, I do not think these drivers have bucking magnets.
There's lots of discussion on which type of glue is suitable. Some say not to use superglue as it is hygroscopic.
The chosen glue must be a slow setting type to allow you time to re-align the magnet assembly so that the voice coil of the speaker moves up and down freely.
A slow setting epoxy would be a suitable choice in my opinion.
P.S. Under the circumstances, I would check the magnets on all the drivers!
Last edited:
Like this 20 minute epoxy:
Sealey SCS400 Slow-Set 20 Min Epoxy Adhesive 25ml: Amazon.co.uk: DIY & Tools
Sealey SCS400 Slow-Set 20 Min Epoxy Adhesive 25ml: Amazon.co.uk: DIY & Tools
As Kay Pirinha says, re-aligning the magnet could be problematical. See this guide:
Resetting a loose magnet (with pictures) | Audiokarma Home Audio Stereo Discussion Forums
Resetting a loose magnet (with pictures) | Audiokarma Home Audio Stereo Discussion Forums
If these are bucking magnets there should also be a cup that wraps around both magnets. If there is no cup I guess they are there to add a bit of extra power to the gap, ie lower the q of the driver. If so, you should put them back with some very thin layer of glue. If they are to add to strength of the original magnet, they shall repell the other maget until they are really close and then attach.
BR,
Anders
BR,
Anders
I see no bucking magnets on the woofers.
https://www.usahifi.com/sites/default/files/product/708/manuals/Heco HiFi The Programme Brochure.pdf
It looks like a former owner glued those magnets to all four of the big woofer.
The much smaller mid-woofer don't have these.
All magnets were glued with their repelling side towards the driver.
From what i read this method was used because the above quoted reasons.
But it also gives a little extra bass-boost.
Maybe i'll glue those magnets onto the drivers again...
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.