crossover burned out tweeters burned out, after a party and 4 hours later and some 😱 drunk dude whacking up my amp to full . so the problem began the mid frequency was not working bought some from ebay months later cause they are very rare any way bought some put them in and well they were also missing the mid freq, so after months of looking and lost music listning time i got tired of trying to do things on the cheap😡 so i ended up buying some new crossovers from the company that took over mission they cost £58 each....i installed them and great the mid the bass freq all back now im installing new tweeters DT-284s but i have to insert a resistor for these tweeters to turn the volume down slightly i know they are 2R2 but i dont know if the watts matter i have some 2R2 3 watts does any one know if these are the right ones are the watts to low ??????????? 
need advice please
need advice please
Is good to use at home (3W). Those are not good speakers (xovers) for parties. If pumping more juice 4x (parallel/series) the resistors, or at least use a 5W or 10W. Also the 7W on the mids and woofers are a little on the low side. You can have peaks more close to 200W (transitories). Thats why the all thing blows, because of that more power that components (caps/resistors) designed for home use don't accept.
upgrade resistors and 2R2 3 watt for mission 753
hi Inductor thanks for your reply it is becoming clear now how rubbish these crossovers are for when you want to push your speakers i was playing money for nothing by dire straits turned up for that great guitar intro and then the music kicked in loud, i had my amp pumping out at three quarters volume a strong amp half way is loud on my other speakers, but any way all i could do was worry about damaging the crossovers i couldent enjoy the music i turned em down thats not right..... until i got these mission753s i have never worried about it i had some great wharfdales had great bass mid and top and a ajustment knob for frequency control on each speaker never worried about turning them up....
if i upgrade as you suggested the coffin type 7watts resistors to what ever say 10watts or more will the coils and caps etc be okay can they handle it at higher power and if i upgrade them would i also upgrade the 2R2 3 watt resistor for the tweeters from the 3watts to some thing higher 5 watts 7 watts ???? my knowledge is restricted so your advice i value thanks 
hi Inductor thanks for your reply it is becoming clear now how rubbish these crossovers are for when you want to push your speakers i was playing money for nothing by dire straits turned up for that great guitar intro and then the music kicked in loud, i had my amp pumping out at three quarters volume a strong amp half way is loud on my other speakers, but any way all i could do was worry about damaging the crossovers i couldent enjoy the music i turned em down thats not right..... until i got these mission753s i have never worried about it i had some great wharfdales had great bass mid and top and a ajustment knob for frequency control on each speaker never worried about turning them up....
if i upgrade as you suggested the coffin type 7watts resistors to what ever say 10watts or more will the coils and caps etc be okay can they handle it at higher power and if i upgrade them would i also upgrade the 2R2 3 watt resistor for the tweeters from the 3watts to some thing higher 5 watts 7 watts ???? my knowledge is restricted so your advice i value thanks
The problem here is time, because we are working on the limits of the speakers. After you solve one problem we need to find the next weakest link. So I already spend a lot of time checking for this speakers some time ago and did a few power simulations. Let's say you can get without the resistors (new designed xover) then we need to check for good components and for the drivers max power, at the same time checking the overall design of the original xover for were the peaks to append in power/component simulation one by one. Is not impossible, but many hours of work. A good speaker (parties) should never have low power resistors in line with woofers, much less components that fail in xover or low power drivers. In a way the xover is also protecting the drivers for wrong frequencies and too much power.
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should i change my speakers
thanks inductor hmmm it could go on and on maybe then do you think because of what i want louder more responsive bass that i should look at buying different speakers with better crossovers do you know of a good speaker like this....dont get me wrong i like easy listning at low volumes but it seems that my missions 753s at low volume tend to loose responsivnes performance in the bass iss poor ??????
thanks inductor hmmm it could go on and on maybe then do you think because of what i want louder more responsive bass that i should look at buying different speakers with better crossovers do you know of a good speaker like this....dont get me wrong i like easy listning at low volumes but it seems that my missions 753s at low volume tend to loose responsivnes performance in the bass iss poor ??????
Follow-up, pls make sure that your xover is the same as this one.
Mission 753 xover
Check your components (one by one) to be on the safe side. (please state your country for when shopping for parts) The 3W resistors are ok for testing on the tweeters for now. That's not an issue. I assume you are testing already, report also for final tweeter xover stage and issues you have now. You can use also a variable L-pad. Buy 2x50Watts (or 100). This will work fine whatever you leave it on (variable L-pad) or substitute it with resistors R1/R2. I take it from you that the tweeter MONACOR DT-284S - 4 is a little on the bright side, please confirm.
Mission 753 xover
Check your components (one by one) to be on the safe side. (please state your country for when shopping for parts) The 3W resistors are ok for testing on the tweeters for now. That's not an issue. I assume you are testing already, report also for final tweeter xover stage and issues you have now. You can use also a variable L-pad. Buy 2x50Watts (or 100). This will work fine whatever you leave it on (variable L-pad) or substitute it with resistors R1/R2. I take it from you that the tweeter MONACOR DT-284S - 4 is a little on the bright side, please confirm.
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hi okay i have purchased new crossovers for my 753s and installed them and i have put in the 284 tweeters and yes the DT 284s are on the bright side.. i already have put a 2R2 3 watt resistor in..and i think it is still a little on the bright side or maybe just a little louder than they should be, what do you suggest i replace the 2R2 3 watt resistor with ???? im nearly there they sound great maybe im not used to them sounding so bright? they sound very responsive now and even the bass seems more punchy
What I would do/test. A variable L-pad can give you the right amount of output on the tweeter assuming that everything else is ok (crossover point/phase correct what might not be the case because you changed tweeters). So on the tweeter leave the initial factory (1+1R) parallel resistors. Instead of your 2R2/3W resistor connect the new variable L-pad to the tweeter, like this one (if you leave them, on the speaker, buy a pair then). Buy a 4Ohm (tweeter) version for the MONACOR DT-284S-04, if you find one.
Parts-Express.com:L-Pad 50W Mono 1" Shaft 8 Ohm | tweeters tweeter pad PA network mounting midrange L-Pads l-pad l pad Crossovers ads 8 ohm
On the woofers if you want more bass/sub, bypass the 2R2 resistor for a more 3dB output (that's almost double the power) or adjust according with a smaller R power resistor (having in mind that the Mid is not changing).
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L pad 50 watt
hi well i had in mind this volume control idea i think i will do this question though why 8 ohms 50 watts the tweeter spec is max 100 watt and its a 4 ohm rated (where do i find the 2R2 for Bass i didnt understand this)
hi well i had in mind this volume control idea i think i will do this question though why 8 ohms 50 watts the tweeter spec is max 100 watt and its a 4 ohm rated (where do i find the 2R2 for Bass i didnt understand this)
I don't know if it's there or not (on the woofer line), you have to find it yourself, it's showing on the xover schematic.
The tweeter will never get so much power, you can use either (50/100W) in a safe away.
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Mission 753 mod for bi-amping
I'm looking at bi-amping my Mission 753's, but there doesn't seem much point when one set of terminals only drives the tweeter. Has anyone tried switching the mid-range drivers onto the same terminals as the tweeter? This would give a more equal power split, but the fact that Mission designed the speakers with the split going between the tweeter and the other four drivers makes me hesitate.
Mission 753 xover
I'm looking at bi-amping my Mission 753's, but there doesn't seem much point when one set of terminals only drives the tweeter. Has anyone tried switching the mid-range drivers onto the same terminals as the tweeter? This would give a more equal power split, but the fact that Mission designed the speakers with the split going between the tweeter and the other four drivers makes me hesitate.
Mission 753 xover
I don't know the reason or a "good reason", just disconnect the cables to the binding posts (from the mid) and connect to the tweeter.
I suspect that the main reason for the biwiring option is just to make more room on the backplate for a bigger crossover. It makes no real sense if you have reasonably fat cables with low DC resistance so your bass stays tight. 😀
It's interesting to follow what happens at loud parties, or when fast tape spooling without mute is applied in studios.
First the tweeter blows and goes open circuit. 😱
Then the tweeter filter is undamped and goes resonant with high current. This fries the 3-7W wirewound input resistor. Actually not too worrying, because it has acted as a fuse and protected the amp from outrageous ~3kHz currents that might take the amp transistors outside their safe operating area. 😎
I have seen these Mission 753 speakers. They have some nice qualities. IMO, the nicest way to mute a loud replacement tweeter is to increase the input resistor and add a Zobel across it, say 7.5R + 1uF for a typical 8 ohm tweeter. Gives better impedance than an attenuator across the tweeter.
It's interesting to follow what happens at loud parties, or when fast tape spooling without mute is applied in studios.
First the tweeter blows and goes open circuit. 😱
Then the tweeter filter is undamped and goes resonant with high current. This fries the 3-7W wirewound input resistor. Actually not too worrying, because it has acted as a fuse and protected the amp from outrageous ~3kHz currents that might take the amp transistors outside their safe operating area. 😎
I have seen these Mission 753 speakers. They have some nice qualities. IMO, the nicest way to mute a loud replacement tweeter is to increase the input resistor and add a Zobel across it, say 7.5R + 1uF for a typical 8 ohm tweeter. Gives better impedance than an attenuator across the tweeter.
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