Hi Folks!
I'm looking to replace the woofers in my old Mission 732's, but it's been a challenge. I searched the internet to see if there was a recommended replacement driver, no luck. I emailed both Mission technical support in the UK and here in Canada and they no longer have information on this speaker - it's rather old now and the company has changed hands many times. So now I'm hoping the great minds on this board might be able to assist.
Here's what the speaker looks like today:
I figure it's probably easiest to replace the entire driver. But without having any of the T/S parameters from the manufacturer, I don't even know where to begin! The only thing I've been able to find is the driver size - 130mm. Thanks in advance for your help!
I'm looking to replace the woofers in my old Mission 732's, but it's been a challenge. I searched the internet to see if there was a recommended replacement driver, no luck. I emailed both Mission technical support in the UK and here in Canada and they no longer have information on this speaker - it's rather old now and the company has changed hands many times. So now I'm hoping the great minds on this board might be able to assist.
Here's what the speaker looks like today:
An externally hosted image should be here but it was not working when we last tested it.
I figure it's probably easiest to replace the entire driver. But without having any of the T/S parameters from the manufacturer, I don't even know where to begin! The only thing I've been able to find is the driver size - 130mm. Thanks in advance for your help!
Not sure where you are located but Ebay UK have these for bidding on. It's one option I suppose. mission 732 | eBay
EDIT: Oh just realized you live in Canada
I do find it odd that the main company doesn't even have any info on the product bearing their name, even if the company has changed hands, they are supposed to at least know the history and product line in my opinion. Slackers .
EDIT: Oh just realized you live in Canada
I do find it odd that the main company doesn't even have any info on the product bearing their name, even if the company has changed hands, they are supposed to at least know the history and product line in my opinion. Slackers .
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I wonder how close these drivers are to yours? MISSION 73-LF58WI 6 1/2" POLY CONE WOOFER/ 6 OHM/ 5 AVAILABLE 732i/733/735 | eBay
I see one of the drivers he is selling also has some cracks on the backside of the cone in his description. Looks like the plastic they used doesn't age well.
I see one of the drivers he is selling also has some cracks on the backside of the cone in his description. Looks like the plastic they used doesn't age well.
The ebay link is a start - those woofers look just like mine. But, I don't want a direct replacement, as the quality of the original woofers isn't that great - I also think there might be an opportunity to use better drivers than the original. Looking around on the net, lots of other ppl have had this issue.
Is there anyway of measuring the T/S of these woofers without fancy equipment?
Is there anyway of measuring the T/S of these woofers without fancy equipment?
Not a clue beyond them being Kevlar and probably Qts of around 0.38 and Vas of 15L. What the guy has done is estimate about 15L reflex and 170mm units...and with any luck the old 2nd order crossovers might well work well enough. You'd need to know if the original drivers are 4 or 8 ohms though...and I wouldn't use Kevlar, but polypropylene is rare these days. Most are paper.
ME, I'd find a kit design with a crossover and drive units to guess if it can be refined. Jeff Bagby, Paul Carmody even Troels Gravesen. But simple crossovers are all the same. 2 capacitors, two coils and two resistors IIRC.
Bet you the bass is around 1.5mH and 8uF and 2.2 ohms for 8 ohm. 0.7mH, 15uF and 1 ohm for 4 ohms. Tweeter will be around 3.3uF and 0.3mH and 2.2 ohm attenuator for 8 ohm. 😀
That cone reminds me of the SEAS H1571-08 U18RNX/P though:
http://www.seas.no/index.php?option=com_content&task=view&id=271&Itemid=247
A rather nice unit. FWIW, if you replace a 4 ohm unit with an 8 ohm, you really just adjust the bafflestep more suitable for bookshelf rather than standmounted use. You might need to increase tweeter level to compensate for the higher efficiency.
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Hi,
I doubt you'll have any luck finding replacements with those frames.
Those drivers do look shot, presumably the cone has hardened and cracked.
But it could appear cosmetically far worse than it actually is, if they are
stress discolourations rather than actual cracks, do they sound bad ?
rgds, sreten.
I doubt you'll have any luck finding replacements with those frames.
Those drivers do look shot, presumably the cone has hardened and cracked.
But it could appear cosmetically far worse than it actually is, if they are
stress discolourations rather than actual cracks, do they sound bad ?
rgds, sreten.
Use Super Cement glue to make many dots in circles around the cone 😀
Feel free to add a midrange 🙂
Feel free to add a midrange 🙂
It's a standard driver under the cosmetic trim:
eshop - Speaker Spares - Mission
Get the measuring tape out and find one that fits the cutout and 4 fixing holes...🙂
Peerless and SB and a few others make poly cones.
eshop - Speaker Spares - Mission
Get the measuring tape out and find one that fits the cutout and 4 fixing holes...🙂
Peerless and SB and a few others make poly cones.
Hi,
No its not. There is no cosmetic trim. Baffle needs modding for other drivers.
rgds, sreten.
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Hi,
yes it is!
rgds, steven. 😛
Just a question of finding something that fits...
Economy SPW165
maybe...🙂
Wow, thanks for all the replies!
sreten, no, the sounds quality seems uneffected. I don't hear any buzzing or cracking.. it might be cosmetic, but I'm hesitant to turn up the volume incase I do damage these speakers - they're my only pair of speakers in the house!
The guy in New Zealand who repaired these speakers in a previous link just replaced the cones with black kevlar, not the entire unit.
So in terms of steps I need to take, do I just order one of those 8ohm drivers and take my chances? Also, it worthwhile to stuff some polyfill (as per the picture above)? The speaker comes unstuffed from the factory.
Thanks!
sreten, no, the sounds quality seems uneffected. I don't hear any buzzing or cracking.. it might be cosmetic, but I'm hesitant to turn up the volume incase I do damage these speakers - they're my only pair of speakers in the house!
The guy in New Zealand who repaired these speakers in a previous link just replaced the cones with black kevlar, not the entire unit.
So in terms of steps I need to take, do I just order one of those 8ohm drivers and take my chances? Also, it worthwhile to stuff some polyfill (as per the picture above)? The speaker comes unstuffed from the factory.
Thanks!
Hi,
If they are not cracks, just cosmetic discolouration, I'd spray the cones
with some black paint and leave as is. Better drivers would be good, but
very hard to pick regarding matching the original x/o.
rgds, sreten.
If they are not cracks, just cosmetic discolouration, I'd spray the cones
with some black paint and leave as is. Better drivers would be good, but
very hard to pick regarding matching the original x/o.
rgds, sreten.
Good luck. I tried looking for a tweeter replacement for a pair of Wharfedale Diamond speakers (no luck).
People won't tell you this, but building speakers is not hard! 😀
Most 6.5" drivers will work in a 15L box. You can play with stuffing and blocking the reflex ports to taste. You can add some cheap 10W wirewound resistors to the tweeter to match the levels. Nothing very critical here. This is not a studio monitor. Like I said, almost anything that fits will likely do, but we'd happily check a locally available contender for you on Qts and Vas an all that. Don't see why you couldn't file off the bumps and fit with bolts either.
I respectively disagree. Not just "any" driver will give him good results. Yes, the QTS, FS and VAS need to fit the desired box size along with an impedance range very close to the original driver, similar frequency response AND driver sensitivity, otherwise it's a crap shoot. Designing a well done speaker IS hard work and not just plunking any driver that fits into the box.I'm guessing he doesn't want to have to wade through 5 or 10 different drivers to get one that kind of works.
Just doing some quick math, 130 millimeters = 5.12 inches. So would I be shopping for a 5 inch driver? or 5 1/4 inch driver.
lduarte1973, DavidL - I agree that a good sounding speaker requires more than dropping in a driver, I'll be trying my hands as building a speaker for the first time (that's for another thread). For this Mission, I'd just like it repaired and not sounding worst than the original design. 🙂
Thanks everyone for the replies!
lduarte1973, DavidL - I agree that a good sounding speaker requires more than dropping in a driver, I'll be trying my hands as building a speaker for the first time (that's for another thread). For this Mission, I'd just like it repaired and not sounding worst than the original design. 🙂
Thanks everyone for the replies!
Mate, you need better than maths at this stage, you need the other engineering skills of SURVEYING and MEASUREMENT if you're gonna progress...
The other issues come later. First find some stuff that might fit. This is what we call being on the "Critical Path" to a solution in civil engineering terms. You do the groundwork first in simple terms. 😎
An externally hosted image should be here but it was not working when we last tested it.
The other issues come later. First find some stuff that might fit. This is what we call being on the "Critical Path" to a solution in civil engineering terms. You do the groundwork first in simple terms. 😎