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Mission 770s hack job on crossover

Audi0

Audi0

Super Member
I just bought some mission 770s freedoms with the matching stands and the crossover has been toyed with on the tweeter side. You can see that somebodys messed with the cap that looks like a piece of candy. I dont know what they were trying to acomplish. All it did was remove low freq cutoff to tweeter. Anyone have the wiring schematic? Both have the same issue.

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Tweeters work thankfully. Look carefully at the pics 2 different glue jobs. The white glue and the old yellow glue. This has been modified heavily.
 
Started reading this in translate. Same speaker different looking crossover

forum.zelfbouwaudio.nl/viewtopic.php?t=23107

file-1.jpg
 
There are a few version's of the 770 freedom crossovers some more complicated than other's.
Glad your tweeters oare ok. Hope you get it sorted there a nice speaker.
:beerchug:
 
boza said:
There are a few version's of the 770 freedom crossovers some more complicated than other's.
Glad your tweeters oare ok. Hope you get it sorted there a nice speaker.
:beerchug:
Click to expand...

You don' have a schematic of any of those versions do you? Pic at least? Did abit of googling and came up with not the info im looking for. Mine are the grey hammered finish versions with seas tweets.
 
No sorry i don't.
I know there isnt a lot of information on the crossovers.
Have you looked on the diy audio forum you may find something on there.
 
Ok so I'm going to dissamble 1 speaker. And write down the finding for the crossover. It's looks like though I was wrong about the cap and tweeter thing. It's 12uf to the tweeter if the caps were hooked up right. Seems like a high value though.

I don' know if anyone can give me a yes or no if it looks right once on paper.
 
Audi0 said:
Ok so I'm going to dissamble 1 speaker. And write down the finding for the crossover. It's looks like though I was wrong about the cap and tweeter thing. It's 12uf to the tweeter if the caps were hooked up right. Seems like a high value though.

I don' know if anyone can give me a yes or no if it looks right once on paper.
Click to expand...

The cap in my 770 mk2 is a 10uf so yours may be right at that.
Are yours the 770 or the 737 renaissance with the hammere'd front panal ?.
 
It looks to be 2 capacitors in parallel. Why is that a problem? Also, the other cap has a resistor in series with it. It looks like the cap was replaced, and the resistor was added to adjust ESR. Again, not an issue.
 
StimpyWan said:
It looks to be 2 capacitors in parallel. Why is that a problem? Also, the other cap has a resistor in series with it. It looks like the cap was replaced, and the resistor was added to adjust ESR. Again, not an issue.
Click to expand...

I mistook the yellow box as a resistor as it was labeled 2r.
 
Not a proper schematic by far can anyone decode it for me? I don't got an inductance tester so inductors are labeled ind. Here it is the diagram and what is changed.
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They look like a early version of the 770 freedom. Yours look like they still use the seas tweeters which are very good.
There doesn't seem to be anything on the internet about them.
Have you sean the article on the 770 on audio4maniacs.
Sorry i don't know how to copy link's but if you serch
Mission 770 audio4maniacs.
You may find some information there.
 
I like boza's suggestion, to check out a Mission forum. You definitely need a Mission fan, that knows the history of the speakers. I even looked on eBay, at 2 different sets of 770 crossovers, and they didn't match each other, or yours. So, short of running into a Mission Guru, I'm not sure what to suggest? Is Mission still in business? If so, maybe they can help?

Also, looking at the 2 schematics you drew, they seem to match, unless I'm missing something? So, what's truly at issue? Confusion that the 2 speakers are different internally, or that they sound dissimilar? If truth be told, mismatched speakers isn't an unknown thing. Manufacturing changes during a production run was common. So, pairs of speakers were sometimes 'odd'. That was 'normal', in my experience.
 
boza said:
They look like a early version of the 770 freedom. Yours look like they still use the seas tweeters which are very good.
There doesn't seem to be anything on the internet about them.
Have you sean the article on the 770 on audio4maniacs.
Sorry i don't know how to copy link's but if you serch
Mission 770 audio4maniacs.
You may find some information there.
Click to expand...

Is this it???

http://www.audio4maniacs.co.uk/blog-article-mission770.html
 
StimpyWan said:
I like boza's suggestion, to check out a Mission forum. You definitely need a Mission fan, that knows the history of the speakers. I even looked on eBay, at 2 different sets of 770 crossovers, and they didn't match each other, or yours. So, short of running into a Mission Guru, I'm not sure what to suggest? Is Mission still in business? If so, maybe they can help?

Also, looking at the 2 schematics you drew, they seem to match, unless I'm missing something? So, what's truly at issue? Confusion that the 2 speakers are different internally, or that they sound dissimilar? If truth be told, mismatched speakers isn't an unknown thing. Manufacturing changes during a production run was common. So, pairs of speakers were sometimes 'odd'. That was 'normal', in my experience.
Click to expand...

I guess I will try a mission forum. Theres a fan club somewhere? Already contacted mission customer support. Those 2 pics was to show what it looked like and the other with red circles are the potential changes. I could remove the suspected changes. The only thing I dont' understand is the changed circuit. It's circled on the pic. Also looking for some sort of ok to due the corrections if it makes sense as my knowledge of crossovers is limited.
 
Audi0 said:
I guess I will try a mission forum. Theres a fan club somewhere? Already contacted mission customer support. Those 2 pics was to show what it looked like and the other with red circles are the potential changes. I could remove the suspected changes. The only thing I dont' understand is the changed circuit. It's circled on the pic. Also looking for some sort of ok to due the corrections if it makes sense as my knowledge of crossovers is limited.
Click to expand...

If the 2 crossovers match, even with the changes, I'm not sure it's wise to remove any parts. That could degrade performance or maybe lead to driver damage. Short of finding an official crossover schematic, the best you may be able to do is match the modded crossover to the unmodded crossover. Both speakers should at least continue to sound the same as such.

One other idea, check with Falcon Acoustics. It's a U.K. parts supplier. They often sell upgrade kits for the more popular British speakers. Maybe they have a kit? If not, they still may know the parts layout for the 770S model.
 
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