Mission M71i Moding

[bull041161]

Hi can any one tell me what mods i can do to improve the sound of my mission speakers

[critofur]

It will be helpful if you send pictures of the insides of the speaker cabinets and measurements of the speakers.

Pictures of the speakers are always nice, though probably not as helpful as seeing the insides.

[ashok]

I don't know what components you have in your crossover.
I upgraded (?) the crossover in my Mission 701's .

All coils with a solid core ( ferrite or otherwise) were replaced with air core coils that I wound myself. For this you will need to remove the original coils and measure them.
Use a software like "inductor.exe" which you can download free from the web , to design your coil. Look for 'Calsod demo' download. It usually comes as an additional free download.

Replace all capacitors with film caps. If they are very large value caps and need to be electrolytic then get something that is better ....like Black Gates ? Anything less than or around 20uF can be all film types. More is possible but can cost a lot. depends on what you want to spend and 'if' large film values will make a difference . In mine I replaced all capacitors with Solen film caps.
I did not change the two resistors on it. I couldn't get anything 'supposed' to be better !

Did it make a difference ? Worth every penny I spent on it!

After that you could stiffen up the box with internal braces front to back and side to side. You can also use damping bitumen panels on the walls. You need to be careful about introducing more material in to the box as it will reduce box volume and change the vent tuning. Some additional stuffing could possibly compensate for that. Better still would be to stuff up the vent and use a sub. Measure the driver Fc and Qtc with stuffed up duct to design the proper eq for the LPF for the subwoofer.

I added the braces but not the damping panels. The speaker sounds very much better with the mods. I forgot to mention that I rewired the crossover and made it a bi-wireable unit ( tweeter and woofer have different terminals).
Cheers.

[Puffin]

http://www.superfi.co.uk/index.cfm/p...roduct_ID/1264

This is what they look like. I would suggest you look at upgrading the crossover components. Are they bi-wireable?

[gabanyayaya]

what I did to my mission was I change to all the Elytonne non polar caps to some Wima and Solen then bypass with Russian PIOs. I rewire back with CAT5. You can also reinforce the basket of the drivers with some heavy duty adhesive to reduce vibration and to add some strength between the basket and the magnets. It change a whole character of the speaker....and eliminate those 'British sound'......try it....

[bull041161]

Hi thanks for replys that helps alot any body any ideas as how much it would cost Also what differance in sound do you get from these mods

[ashok]

If you have the faintest idea how much it will cost then surely no one else does ( for your crossover )!

The only way you can know is to open up your speaker and take out the crossover board and post the photograph here. Then maybe others could give you a reasonably good idea how much it will cost.

Without that it will be a shot in the dark. A guesstimate could be
$20 to $200 ! Depends what needs to be changed and what the values are. Depends on brands too.