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A German site has released details of how they repaired a set of Mission 753 Loudspeakers that were sporting a blown tweeter. 

Visitors to Justblair.co.uk frequently contact me for advice on how to deal with blown tweeters on the Mission 753 Speakers, it seems that the tweeters are the least resilient to party type abuse!

As the speaker is about 15 years old now, unsurprisingly the tweeters are no longer available as replacement parts.  This leaves the owner with two choices, either find a specialist who can rewind the melted voice coils or find an alternate part that will play nice with the bass drivers and crossover. 

When asked to repair a set of Mission 753’s Hifi Selbstbau took a methodical approach to find drivers that would make a good match to the speakers. 

They started by testing the circuits that were there, in the process realising that the high frequency circuit was behaving in a pretty hazardous manner with the blown tweeters in place. 

The closest match that they found to the Mission 753 drivers (A peerless made driver) was the DT-284S  from Monacor which they reckon may even improve upon the sound of the Mission 753 speakers.

A small change to the crossover was also required adding a 2R2 in series resistor to replace the 0.5R value that is already there.  This is to reduce the volume slightly on the Monacor driver.

The driver of course does not match the mounting for the original Peerless driver, but only a  little surgery to the mounting plate was required. The result (seen above) looks very much like an original manufacturer part.

If you own a broken Mission 753 Speaker or are just plain interested in knowing more about this classic design, I would thoroughly recommend aiming your browser at this article, There is loads of info there on the speakers…

Mission 753 Tweeter Replacement