Speaker repair/replacement

[Wozzaaah]

The woofers on my trusty old Mission 733s are disintegrating, you can no longer get any original parts for them but I've found a pair of suitable replacements made by Monacor.
Even though they're badly cracked as shown they still sound great so....do you think the Monacor drivers would make much of a difference to the overall sound and at £60 for a pair would it be worth it?
I've seen people that can re-cone them though to be honest I expect that would cost more than the Monacor ones.
I'd hate to throw them away but at the same time I'd hate to throw £60 at them and be disappointed with the result.
I bought them new back in the 90s and at the moment they still sound every bit as good as they did when I bought them but it's only a matter of time before the cones fall apart completely.

 

[MattH]

I very much doubt that the new drivers will sound the same. Even if all the parameters on the new units are identical (which they wont be) then you'd still hear a difference.
That being said the same will hold true of a re-cone as i'd be very surprised if the same materials as the originals were used.

You might be better off hunting down a decent condition secondhand set.

 

[rikrobson]

What the hell have you been playing?

 

[rikrobson]

Or do you have a Spinal Tap Amp that goes to 11?

 

[Wozzaaah]

It's a common fault with the 733s, they go brittle with age.....especially if you leave the grilles off.......so I've just found out......

 

[colnerov]

There's probably already a difference with them cracked like that, you haven't noticed because it's been gradual.

 

[ajlelectronics]

Could you lay a fibreglass tissue layer over it to regain the stiffness?

 

[Wozzaaah]

Could you lay a fibreglass tissue layer over it to regain the stiffness?

Possibly, but wouldn't that affect the sound?

 

[MoreWellie]

Even before they cracked I suspect the sound would have changed gradually as the cones hardened

I cannot see that re-coning by anyone but the original manufacturers would come close to the original frequency and efficiency

Wilmslow have been around for decades and as they mention the missions the monacor ones have to be worth a try and £60 is a lot less than a decent quality pair of new speakers

the ear would be a lot more tolerant about changing the woofers than any of the other drive units

 

[ajlelectronics]

The cone is stiff and moves as one piece against the suspension. Therefore I can't see how a layer of tissue would hurt it, as long as the suspension wasn't affected.

 

[richie00boy]

Adding fibreglass will change the weight, which will change the bass response. Being polypropylene it maybe won't stick very well anyway.

Also, the cones don't move as a pure piston, they flex with more nodes depending on frequency.

As already mentioned the Monacor drivers will have different parameters and a different sound. But they may be an ok substitute, worth a gamble at 60 quid.

 

[Wozzaaah]

Even before they cracked I suspect the sound would have changed gradually as the cones hardened

I cannot see that re-coning by anyone but the original manufacturers would come close to the original frequency and efficiency

Wilmslow have been around for decades and as they mention the missions the monacor ones have to be worth a try and £60 is a lot less than a decent quality pair of new speakers

the ear would be a lot more tolerant about changing the woofers than any of the other drive units

I've found a couple of posts where people say they aren't happy with the Monacor ones or that they're not compatible with the crossover.

The cone is stiff and moves as one piece against the suspension. Therefore I can't see how a layer of tissue would hurt it, as long as the suspension wasn't affected.

I have thought about brushing some sort of resin on the back of the cone to try and extend their life but I'm not sure what would be good to try as it's going to be a one-shot thing.

 

[octo0072000]

just try some clear high modulus silicone on the back of the cracks just a thin layer cant be any worse than they are now

 

[the snooper]

The cone is stiff and moves as one piece against the suspension. Therefore I can't see how a layer of tissue would hurt it, as long as the suspension wasn't affected.

It would sound terrible, you could compare it to tapping a 4 inch piece of wood then same in steel, it would be totally different

 

[Kayos]

I tried some monocor drivers in a car, they went binwards

Look on Europe audio, Dayton Audio reference will be my choice for the next install

 

[ajlelectronics]

It would sound terrible, you could compare it to tapping a 4 inch piece of wood then same in steel, it would be totally different

Not the same. The cone is a device that moves air. Stiff is better, which is why upmarket drivers use Kevlar rather than paper. The cone moves in a linear fashion, in and out against the suspension, under command of the voice coil. Therefore I fail to see how it would be a bad move.

 

[the snooper]

The woofers on my trusty old Mission 733s are disintegrating, you can no longer get any original parts for them but I've found a pair of suitable replacements made by Monacor.
Even though they're badly cracked as shown they still sound great so....do you think the Monacor drivers would make much of a difference to the overall sound and at £60 for a pair would it be worth it?
I've seen people that can re-cone them though to be honest I expect that would cost more than the Monacor ones.
I'd hate to throw them away but at the same time I'd hate to throw £60 at them and be disappointed with the result.
I bought them new back in the 90s and at the moment they still sound every bit as good as they did when I bought them but it's only a matter of time before the cones fall apart completely.
View attachment 81410

Don't think I would entertain that replacement you have listed they have listed sensetivity in volts at 1 mtr it's usually 1 watt at 1 meter and they are not very efficient at only 88 db

 

[the snooper]

Not the same. The cone is a device that moves air. Stiff is better, which is why upmarket drivers use Kevlar rather than paper. The cone moves in a linear fashion, in and out against the suspension, under command of the voice coil. Therefore I fail to see how it would be a bad move.

Because the material still has to transmit the sound to the air in the first place

 

[ajlelectronics]

Because the material still has to transmit the sound to the air in the first place

It does that by moving the air though!

 

[Welderpaul]

Wow, they are old! I had a pair when I was a spotty 18 year old. I remember buying them from Richer Sounds and bringing them back home on the bus.

Mine were black ash. All the rage.