Crossover suggestions

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Rebuilding or building new boxes for a pair of missions 760I

Looking to upgrade the crossover parts, any suggestions?

speaker build with missions | Ill try to remember always

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upgraded parts

Upgraded parts can indeed make a difference. IME I found that in most speaker line ups that use the same drivers throughout the line, the lower priced models most often have lesser quality parts in order to hit the intended price point (and I think also so there is more of a difference than just bass and max SPL as you move up the line)....

Most will suggest that you change all the in series caps with a quality film cap, especially to the tweeter. It can effect the output level of the tweeter so you might have to tweek the value of the in series resistor to match the original level. I have also found that the in series resistor can make just as much of an improvement. Metal film or wirewound are usually what I look to.

I have found that replacing the in series coil to the woofer with flat wire coils will improve the midrange substantially. Have to be more carefull with the coil as they will have different DCR values with the same inductance. If you are off to far on the DCR the level will change which is not easily correctable.

Good luck.
 
Unless I missed something, the mission 760i wasn't exactly high end in the first place, the drivers will be cheap and low quality in comparison with the level of crossover components being recommended here by other members.

jjrenman - I'm sorry I'm not entirely understanding what you're saying, is it that the same drivers are used in high end and low end speakers within the same manufacturers? Also can you link to some examples of the flat wire coils you're suggesting? I would agree that a film cap is better than what's here, but I'd seriously question if the tweeter in this unit is worth the investment.

salsalyatorereda - i wouldn't bother because of the time and effort you've put into making cabinets, considering the cost/work/reward ratio, buying relatively cheap drivers would perform many times better than what you have.
 
"nannoo",

Ratio of parts cost has nothing to do with it. Just like your audio system is a "chain" that is only as good as it's weekest link so it is within the "chain" of parts within the speaker. We are simply sugesting upgrades because the weekness in this particular speaker is in the x-over parts. Some very well regarded high end speakers in the past have used very inexpensive drivers with very good x-over parts!

As far as using the same drivers I am refering to a specific "line" from the same maker. With Mission you will notice that the MX and SX lines use different drivers but within the SX line you will notice that there will often be a smaller model that use fewer of the same drivers and in a smaller cabinet. It is my experience that the x-over parts in the most expensive speaker within that same line will have better x-over components in it.

I do not accept that the tweeter here is not worth a better capacitor. I've heard to many speakers with excellent sound where the maker had put more money into x-overs than drivers. I've even heard Mission speakers, using the same tweeter in the higher models, that have a much better sound from the same tweeter.... BTW do you think speaker wire makes a difference? If so than why would it not make a difference on the inside of the speaker? Let alone the quality of the rest of the parts.

As far as flat wire coils go both Parts Connexion and Parts Express carry them.

Lastly, I have read your post many many times and still can not figure out why you claim the mission drivers are cheap so don't bother and then you turn around and tell him to go get some relatively cheap drivers that would work better? So which is it cheap drivers will or won't work better?
 
urgh, this is getting boring.
The mission speakers were £120 in uk in 1993. At a real push that puts them at about £200 in modern day terms, That means cost price for the speakers would have been around £50. That can be split into labour, packaging, electrical components and cabinets.

This isn't rocket science. they were very cheap drivers, and they will never sound 'amazing'. You could maybe get a little improvement from a better cap, but I really doubt it's worth it, spending £4+ on a capacitor for a driver that cost the equivalent of £7 just makes no sense.

The whole point of DIY is meant to be to cut out the additional costs whilst also tailoring to your own sound.

Yes speakers in the same product line use the same drivers, and the larger speakers may get slightly nicer crossovers, for a multitude of reasons. this doesn't mean that a cheap speaker is going to have amazing drive units in it, or that a cheap speaker has really high quality drivers like in a high-end speaker.

So, in short, for a relatively small investment, with care taken over driver selection and crossover parts, you could expect a huge increase in performance. because 'cheap' drivers will still be better made than in the old missions.

What exactly is your experience in this industry?
You sound like a blag artist to me.

Speaker wire makes a very small difference, for gods sake please don't start another subjectivist/objectivist debate.

Next you'll be telling me to upgrade my £1 digital cable in my £5000 system...
 
Give it a rest.

I've been in the industry for over thirty years.... Selling, manufacturing, installations, modifications, 2 ch or multi cahnnel, simple rooms all the way up to multi million dollar theaters so if I sound like I have some experience it is because I do. I personally have experience trying many different levels of parts in speaker brands from an entry level Polk audio all the way up to B+W's and nearly everything in between. In many of the cases the changes were presented in listening sessions to a group of listeners so that the sound differences could be discussed.

It is not so much boring as it is frustrating to defend why parts quality can make a such a difference to someone who states "speaker wire makes a small difference" and no, I am not going to suggest you change your digitle cable to something very expensive, if what you have sounds great then sit down and put on some music.... Some of the best wire I have is from liquidation bins. Pretty cheap unless you include the hundreds of hours spent listening to the different types, constructions etc. BTW I am often amazed that some of the most expensive equipment in the world is actually not that good.

Your blanket statement about any new cheap driver is better than old cheap drivers is absurd. In fact it is company's like Mission that use there engineering and manufacturing spend to get cheap drivers to sound good.

In closing I actual envy you. I often wish that I could not here the differences in so many of the little things that do make a distinct difference. Think of all the time I could have spent enjoying the music which, in the end, is the only reason I deal with all the equipment and junk to begin with. I do not know what level of performance you can get to with the mission drivers but I am by far and away not the only one that has experienced substantial improvements by doing parts upgrades and the whole point on a DIY site is to dare I say it "Do it yourself".

PS- As to being a blag artist, if my "self gain by using clever talk" is to give myself a raging headache than I have succeded in gaining indeed!
 
jjrenman,

You don't sound like you have experience, you sound clueless. You provide no factual evidence to back up your statements despite multiples requests.

Of course the cabinet makes a difference, and a well made/designed cabinet will blow away a badly made one, and a company like mission should know there driver units well enough to build a pretty 'ideal' cabinet for them in the first place, so why DIY a new cabinet for them?...

Positives:
You could end up with a speaker that competes with speakers costing twice as much

Negatives:
All the driver data is likely unavailable, and testing it as a DIY noob is difficult, costly and time consuming.
Adjusting the design to get the best performance possible out of the mission drivers will be difficult. It is unlikely that the improvement in sound quality will be the same as the potential available.
If you're going to invest the time into making cabinets from scratch it would make sense to find drivers that work with your design, and achieve an improvement in performance over what you have.

I explained to you why I believe the drivers in the missions would have been cheap. This doesn't prevent them from sounding good, it pretty much makes it a physical impossibility that they could ever sound amazing. Especially when you consider manufacturing methods, accuracy, consistency, compexity of design (in relation to manufactured form) etc etc etc.

I never said 'any cheap driver'. I said a carefully chosen driver. The Tang Band W5-876SE for example, available on parts express for just $19, should blow the existing woofer away for SQ.

Of course upgrading the capacitor could sound different or even better, I never said it wouldn't, i said I wouldn't bother, and you've given me no reason to change that statement.

I asked you not to start a speaker-wire debate, but you have anyway, so please tell me how you have heard the difference between directional and non-directional wire, tell me how you can hear the difference between any two digital cables you care to choose as an example.
 
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1) I'm just giving my opinion on my experience with speaker upgrades.

2) IME as a consummate DIY'r it takes far more experience, knowledge and test equipment to design a proper crossover than it does to improve the quality of the parts so why not see how far upgraded parts will take you. IMO the experience gained in doing so is invaluable for, when the time comes, someone is ready to upgrade a driver as the original poster suggests that he will eventually do.

3) Not sure what facts I can give you as most of what I have been talking about comes from decades of selling, repairing, manufacturing and upgrading speaker systems. If the OP wanted the "facts" behind speakers I would have referred him to some of the texts I have found most use full such as "Loudspeaker Design Cookbook" by Dickason or "Acoustical Engineering" by Olson.

4) Not debating wires, in fact I was supporting you in the fact that not all wire has to be expensive to sound good. BTW since music is A/C there is not a direction to it, more of a push pull kind of thing. Wires with arrows on them are usually referring to what end the shield is attached to.

5) I do not wish to debate wire differences and you have asked me not to debate wire differences so I will ignore your question about digital cables however if you want to start a new thread in the "Digital audio" section I will be more than happy to share my experiences and opinions with you.
 
Sometimes changing electrolytics for polyprops makes a big difference, other times it does nothing and i've even heard a few people say it sounded worse, but you'll never know if you don't try.
The budget Mission m70 responded very well to a polyrop cap upgrade when I tried it. With the AR18 there was no difference.
 
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