Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems G68 power supply failures - Please report

Just received my XP power supply from Farnell.

I have not opened the G68, so not sure about the state of the various caps (tech note TN32) As my current power supply hasn't really failed (see story above) I probably should not have to replace them, but as the G68 is opened up anyway, I might as well.

Any suggestions on the make and type of the caps ?

What board is the 'GOEA PCB' ?

I'm tempted to do the same as my 2005 G68 PSU must be living on borrowed time. Is it the XP Power ECM40UT31 you've gone for. I was toying with idea of fitting the slighly more powerful XP Power ECM60UT31 in the hope that it would run so a little cooler

Anybody ?

I'm currently planning a replace in my opened G68 with Panasonic 105c caps I have ordered, to come today or tmr. For the power side you can really take regular caps, no need for Nichicon Muse, etc. I think in there are Jamicon rated at 85c.

The board I cannot tell, would need to check with my G68 at home (all cards currently in a carton)

I found in my G68ADV a "R"GOAE_2 and that is the digital out card for non SL DSP speakers.

When I exchange the caps on my analogue audio card I will stick with Nichicon caps, the ones Meridian does use in production:

http://www.nichicon.co.jp/english/index.html

Thank you Andreas. That is a big help.

Saves me a lot of downtime. Now I can order the correct parts and get my friend to install the replacement caps at his workstation, the proper way.

Sure, anytime. I also noticed in some pictures the shift from golden to later more greenish looking Nichicon ones. If you dive through the Nichicon section of audio caps, there can be even headroom for better ones than from factory. Nichicon has per audio cap line a PDF online, that shows the possible up-grade path. To me the ones on the analogue card I have look more like golden "standard" ones, not even "Fine-gold" or "Muse" series. So pick the best to needed spec

My caps are still overdue, drives me nuts. So I'm spending the time on PCB cleaning of colophony rests somebody left

Btw, it could be an idea to start in a different thread a list of G68 card names and specs....

My caps came...finally. As my G68 was stripped, it took me just a couple of minutes to solder them in. You really need to take the main board out to work properly, which I did.



My audio problem is not cured, but after a bit more testing I still have that analogue card more and more under suspect. The G68 runs with the new caps as fast as before on IR commands, if not felt even a bit faster. You can really fly through menus. Really nice, a good feeling to see all new and to work out so nice.

Now I need to get a few more caps for the other cards mentioned. A pity that Meridian did leave so little space between sections / card slots. A lot of nicer caps, like Nichicon KZ / KA / FG are thicker to spec, if I read the data sheets correctly and during re-assembly, one feels how tigh the G68 is with 10mil caps. I guess 12 or 15mil caps will not fit in anymore at all, too thick We'll see....

Since Friday close after the "re-caping" my G68 has made it back to an all time high in sound quality I have not had before. After the disappointing re-assembly of the cards without screwing all back panels in ( a good decision), it was not any different than before as written in the post above, so I decided to take out the cards once more and try more points on my list.

So far I can say the PSU and cap swapping did bring the machine back to live, to speed, not to sound....but maybe I'm wrong.

So the next two points on my agenda were to change the refit procedure of cards and to tape on of the two bigger 10x20mm caps I found under suspect on the audio out card, that had a a very small scratch in the shrink foil from the legs of the processor card above it. It is actually quite annoying to refit cards, as Meridian preferred not to shave off legs of capacitors and resistors looking through the card's bottom hooking into the parts of the card below.

That changed it all. I cannot tell, if it was the card refit procedure according to technotes or the cap taping, or at the end the power caps needing time to come to life, but all is stable and just plain awesome since late last Friday and yesterday and today I just let it flow, can't get enough. Details, bass, liquid Meridian sound as desired. My 561 can get back on the back up shelve.

Personally I assume the following. The scratch in the power cap came from a former service, due to the little space between cards. So a small short between the caps aluminum housing and some legs/pins of the processor card above it can have irritated the processor card or the analogue output card. Maybe all three points were the reason. I cannot tell. However after the third day I feel confident to say that my G68 is cured for just 70 Euros spent.

I may continue to tune the analogue card with different caps. Will report back once I find something of significance in sound.

I replaced my PSU after a couple loud pops and a non responsive display. The sound also became 'thin' every now and then and I found the G68 ran pretty hot. Measured as per the wiki and noticed the voltages were off.

I ordered a new one from Farnell (I already had an XP unit, so ordered same), came in next day! Lots of screws but quite easy to install.
I tested first with 5.0V but found the volume now slow in response. Tweaked it up to the recommended 5.2V and everything worked like a charm. Great sound and the unit now runs cooler.

Easy fix, 50 euro in parts, and all back up and running, better than before. Happy camper here. Thanks for all the hints and tips on the forum and wikie, I would never have started without it...

Same thing with my G61R. Processor would work for a short while and then reboot itself, sometimes the relays would click away for a while before stopping. Upped the 5v pot to 5.2v and I'm back in business. Ordered a replacement PSU from Farnell and will fit that tomorrow.

Big thanks to Chris JC for helping me out last night

I've got a 3-4 years old G68ADV from one of my old clients, not working. Checked out this thread and decided to fix them using my repair guy. So, couple of questions.

The tech note advises to change several caps., a few of them don't look good in my case, but the rest of them are not blown. What do you think, should I nevertheless replace them all?

What kind of PSU from XP power will be the best to fit in the unit in terms of easy mount to existing holes? I'm looking at ECM60UT31, but it's slightly bigger than the original one.

Could you please point me to the wiki page that people are talking about earlier in this thread?

Thanks a lot!
Oleg