lcr thx 750

**nickjob1** · **11-01-08, 12:28 AM**

HELP!!!
Cranked up my system a little too much and now my thx 750 rears have no tweeter noise. Couldn't find anyone to work on them and M&K out of business. Wasn't sure if the tweeters were fried or something else. Took up upon myself to further investigate. Found a capacitor on the crossover board with the top blown off. Seems the whole board is Elytone parts, or they manufactured the whole board. The capacitor blown up is labeled 12 uf +/- 10% 50V NP by Elytone.
Question is: Can I replace this capacitor and be back into rear tweeter sound, or do I also have tweeters to replace. Also, can't find the exact capacitor rating of 50V, only 63V. Will that have any effects.
Thanks for the info, want to get back up and running
Nick

**drdoan** · **11-01-08, 12:59 PM**

Nick, you can use the 63v cap as long as the capacity is the same (12uf) and it is non polar. You can check the tweeters by first using an ohm meter to see of the reading between the speakers' leads is around 8 ohms or so. If that is ok, try intermittently touching the leads of the speaker with a AA battery to hear if any clicks come out of the speaker. If all goes well, try applying audio to the speaker and listen for proper sound. Hope this helps, Dennis

**thxgoon** · **11-01-08, 01:41 PM**

M&K is back in business though not distributing in the US yet. I had a similar problem about a year ago and contacted the new company. They were very helpfull and seemed willing to work on the old products.

http://www.mksoundsystem.com/

**nickjob1** · **11-03-08, 08:12 AM**

Dennis:
Thanks for the info. I'll give that a try.
Regards,
Nick

**nickjob1** · **11-15-08, 01:26 AM**

Dennis:
Changed out one speaker with the new capacitor, plugged it in, works fine. Said this is great!
Went to change out the other speaker, found this one not blown up like the other, but replaced it anyway. No luck. So I did the check on the tweeter with the meter, nothing. Did the test with the battery, nothing. Looks like I need a new tweeter.
No luck finding anything on the web with the label on the tweeter. Z11 MK TV 4 ohm----------990524.
This is a pain trying to get a replacement. Great speakers, but what a pain to find anything M&K replacement.
Thanks for the help.
Regards,
Nick

**thxgoon** · **11-15-08, 10:46 PM**

Have you tried writing the company?

**Aaron Gilbert** · **11-16-08, 12:54 AM**

To my knowledge, those tweeters are not yet available from the new company. My company has been trying to get a hold of them for about a year now. They do keep promising to support the older products, however, and much of their new product line looks identical to the old. So there's hope.

nickjob1, where did you purchase the LCR750s? If it was from a Magnolia Home Theater, I might be able to help you out.

**nickjob1** · **11-17-08, 03:52 PM**

I purchased them at a local home theater store that is now also out of business.

Advertisement