Hey everyone. So naw my Mission 770
from back in the day will have new woffers. The tweeters, i will have a go at cleaning out old ferrofluid if not capable of doing this well suggestions are welcome. A full clean up of the cabs
Age related scuffs nothing deep.
How shall I go forward with my new task? I've had a look inside and the foam in good nik, very dense and firm. Interior panels have got about 5mm thick black dampening pannels stuck on. I need help on
1 best way to make exterior shine
2 the tweeters, clean or replace
3 crossover back into spec
4 interior wireing change for high quality
5 your suggestions and experience
Thanks
from back in the day will have new woffers. The tweeters, i will have a go at cleaning out old ferrofluid if not capable of doing this well suggestions are welcome. A full clean up of the cabs
Age related scuffs nothing deep.
How shall I go forward with my new task? I've had a look inside and the foam in good nik, very dense and firm. Interior panels have got about 5mm thick black dampening pannels stuck on. I need help on
1 best way to make exterior shine
2 the tweeters, clean or replace
3 crossover back into spec
4 interior wireing change for high quality
5 your suggestions and experience
Thanks
Never refurbed a set of Missions but in the spirit of open discussion on the forum the following springs to mind!
#2: If you can find tweeters then personally I would replace them. Keep the old ones, though. just in case you prefer them over the new ones!
#3: Wouldn't think that anything needed doing unless there are any electrolytic capacitors: maybe change them as they don't age well.
#4: Good idea but asking for specific advice on speaker cables is probably going to open a huge can of worms as cable discussion nearly always does. I just put the same cable IN cabinets as I run from the amp TO the cabinets - works for me!
#2: If you can find tweeters then personally I would replace them. Keep the old ones, though. just in case you prefer them over the new ones!
#3: Wouldn't think that anything needed doing unless there are any electrolytic capacitors: maybe change them as they don't age well.
#4: Good idea but asking for specific advice on speaker cables is probably going to open a huge can of worms as cable discussion nearly always does. I just put the same cable IN cabinets as I run from the amp TO the cabinets - works for me!
Re #1: I presume, Barry, that your original late 1970s Mission 770 speakers are clad in real wood veneer. If so, is the finish oiled or varnished?
Re #2: I read that the 25mm SEAS soft-dome tweeter was shown to dip away by about 4-5dB above 5kHz to produce a slightly muted treble. So yours may be performing as designed.
Re #3: I agree with robski regarding the possibility of replacing bipolar electrolytic capacitors in the crossover.
Re #4: Do not use heavy gauge speaker cable internally as its weight may put undue strain on the driver terminals.
Re #2: I read that the 25mm SEAS soft-dome tweeter was shown to dip away by about 4-5dB above 5kHz to produce a slightly muted treble. So yours may be performing as designed.
Re #3: I agree with robski regarding the possibility of replacing bipolar electrolytic capacitors in the crossover.
Re #4: Do not use heavy gauge speaker cable internally as its weight may put undue strain on the driver terminals.
I've found this image of the original Mission 770 crossovers that was supplied by member slipmyster.
The tan coloured single capacitor at the top is a film type which does not degrade over time.
If your capacitor looks like this there's no need to replace it, but you may be tempted to upgrade it.
The tan coloured single capacitor at the top is a film type which does not degrade over time.
If your capacitor looks like this there's no need to replace it, but you may be tempted to upgrade it.
Thanks guys. . The original internal wiring is thick and heavy. When I took the woffer out the driver terminals where all loose. Hope the woofers from the 737r terminals are ok. Keep it simple and don't do what doesn't have to be.
Sorry Galu. I will take photos of the originals and post them. They are just like the photo above, thay look very dry if you get what I mean. I will take pics now.
Thay look rough, I been using them in my room being dragged arround. .very bad.
I'm sure abit of elbow grease with your help on what to use and the like thay should be fine. I think!
I'm sure abit of elbow grease with your help on what to use and the like thay should be fine. I think!
Attachments
Thinking about the interior wireing, I had to replace my old original driver because the terminals had been over stressed.
The tweeters stopped working a while ago. I extended the cable that run to the tweeter and connected it to a small 2way kenwood speaker from a little middy system 6ohm's thay are so its a bad tweeter. Thay sound ok but I want the original sound back. .have you ever listen to them Galu?
The tweeters stopped working a while ago. I extended the cable that run to the tweeter and connected it to a small 2way kenwood speaker from a little middy system 6ohm's thay are so its a bad tweeter. Thay sound ok but I want the original sound back. .have you ever listen to them Galu?
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Thanks for the memories -
The Mission 737R were the speakers in my first Real Hifi alongside a Sansui AUG30x amp and Philips CD Player CD360 and later adding an AR EB01 turntable. Bought from Sevenoaks Hifi in Brighton UK using their Magic Matrix sales from the late 1980’s. (Note at this point in time I was earning £2.79 per hour).
Sorry to derail the thread, please resume normal service.
The Mission 737R were the speakers in my first Real Hifi alongside a Sansui AUG30x amp and Philips CD Player CD360 and later adding an AR EB01 turntable. Bought from Sevenoaks Hifi in Brighton UK using their Magic Matrix sales from the late 1980’s. (Note at this point in time I was earning £2.79 per hour).
Sorry to derail the thread, please resume normal service.
No worries Ugg 10. 737r drivers were as of what I've read the last and final evolution of the originals that would have been maybe 4/5 years later. Thay must have been great to kick back and have a listen too.
I like my vintage gear. Starting to collect again. .im nearly 50 so remembering reading all the "what Hifi" mags. But that would have been the 80's I prefer the gear before then the good old stuff!
I like my vintage gear. Starting to collect again. .im nearly 50 so remembering reading all the "what Hifi" mags. But that would have been the 80's I prefer the gear before then the good old stuff!
Thanks for the pics.
I wouldn't try sanding as you may go through the thin wood veneer before removing deep scratches.
One suggestion is to prepare the surface with medium grade wire wool dampened with methylated spirits and, when dry, apply a beeswax finish.
That wasn't quite clear in your introductory post. Did you hope that replacing ferrofluid would coax them back into action? Are you up to spending on a suitable pair of replacements?
I'm afraid not, Barry.
Memories indeed!
I once had the Mordaunt-Short MS10 and QED A240CD combination offered on that Sevenoaks mix and match list.
And surprisingly good the combo sounded too!
You haven't said if the tweeters are actually producing sound. If not, replacing the ferrofluid is unlikely to coax them back to life.
Would you be interested in substitute tweeters? If so, please measure the faceplate diameter of your current tweeters.
I believe the original SEAS 25 mm dome tweeters were 6 ohm and we may be able to locate an alternative that suits your budget.
O.k. Gallu. Budget wize I want to raise it by selling 2 thorens td150 mk1 and mk2 turntables full working order but I have to go further in detail about the mk2, also have for parts, Pioneer SA606 amp. power switch broken but does work, SQ is distortion. Sansui R50 parts, its a mess inside but you have sound.