Hi all,
I sure wish I could read more of this awsome website - I can only read English. 🙁 I have spent a lot of time using language translators when I visit here and I really love this site.
On to my question... I have 4 pairs of DSS-930 speakers. A few of them have died in the past and each time, I was lucky enough to find a simple 500mA fuse had blown. This time is not the case. I have the Service manual but it is a poor photocopy I bought from another website devoted to Philips/Marantz. When I replace the fuse, it immediately blows when powered up. Does anyone have an idea what may be the weak link on these speakers since I have a common problem of popping the fuses located at 1406 and 1407 of the interface/power supply?
One clue about the possible cause for my frequent fuse popping may be that I leave the speaker power switches always on and use a light switch to toggle the wall outlets.
Thanks so much in advance and again for this website. 😀
Ask Movieman, he knows all there is to know about DSS speakers.
I´m sure he can help you 8)
Hi,
People see mee as a DSS-expert, dunno why, but ok... I'll give it a try...
I've never had or heard of such a problem in a DSS. Since your fuse blows each time, my guess is that there's a short-circuit somewhere, your (diode)rectifierbridge or the voltageregulators might be defective on the board...
You might check those or just replace them and of course the 4 capacitors, they could be worn out.
Good luck. 😉
He knows you know 😛 (Marillion)
Thanks Remi and thank you m0vieman for the hints. I will give it a try and let you know the outcome.
In the meantime, I guess I will just have to settle for the 7 remaining speakers for 2-channel playback 😈
Apart from what movieman suggests, I would also check the voltage regulators on the same pcb.
In many cases their terminals are loose.
If so, you may need to replace them (just to be sure) Loose terminals could harm the regulators, you might be lucky. Then just fasten the regulators and replace the fuses.
positions are: 4707 , 4708, 4709. (optional 4710)
Anyway : check the regulator terminals in all your DSS speakers.
You could also take out all of these regulators and see if your fuses survive. If so : bridge rectifier 4604..4607 and caps 2415 + 2418 are okay. Please keep in mind to discharge these caps afterwards.
Good luck , and please let us know if it works.
Wow herman! I am now getting very optimistic that a fix is possible. I will get back with my findings.
Hi again,
What did you mean by saying "they died" and what did you do with the defective DSS? What was the exact problem?
In 99 out of 100 cases a malfunctioning DSS is caused by bad solderspots of the chinchconnectors on the interfaceboard. Often the hexinverter (SMD IC on the same board) is broken.
Greetz. 😉
It was two or three different speakers exhibiting the same problem. I would turn on the light switch that goes to the outlets for the speakers and I noticed that one speaker had no lights on in the front LED - the speaker was "dead" - no sound at all. The first time this happened, I just poked around a bit with an ohmmeter and found that a fuse located at 1406 or 1407 on the interface/pwr supply was bad. These are the little cylindrical black 500mA ones. I jumpered the fuse and the speaker worked fine. So I then ordered a bag of them from Mouser.com to fix it right. The second and third time (different speakers), I headed straight for those fuses and sure enough, same problem. What I don't quite understand is if the fuses are just getting old and possibly corroding/deteriorating internally causing them to blow or if some other component is wandering from its specification and causing the fuses to blow. I hope that helps explain a little better.
LOL @ Herman!
Jumpering fuses is not a wise thing to do. You know those parts have a certain purpose... 😯
Greetz. 😉
Well, I just informed you, in case you're gonne try anything funny, like for example a lawsuite or worse a Jerry Springer visitation LOL. 😀
Greetz. 😉
😀 😛
no luck so far. I removed the regulators and my fuses still blow. After testing every component on the board (no apparent problems), I changed the caps 2415,2416,2417,2418 - no luck. Then I replaced the diodes in the bridge rectifier - no luck. I then replaced the 4 voltage regulators with new ones anyway. I tried to test all of the tiny surface mount caps and resistors on the underside but that is very tedious and I'm not sure if I can say they are all perfect given that I did not remove them for testing. Then I replaced the hex inverter and the quad op-amp ICs on the bottom of the board - again no luck.
another thing i tried was to simply swap out the whole power supply interface board from a good speaker. it worked so I do know that my problem lies in this interface and not beyond it like say in the transformer.
any other ideas before I go find a professional electronics shop?
Thanks again for all of your ideas. I was very hopeful and I had fun trying to fix this but now I think I am tired of poking and hoping.
Cheers!
