I measured the -15V voltage regulator IC6 that is connected to C40, which seems to be ok. Any other components I should perhaps check?

Dillen wrote:

MKS is probably not the worst choice here, but I really would have chosen tantals for the two in the remote receiver amplifier.
B&O chose to use tantals here for a reason.

Thanks Martin, very helpful. I'll order some tantals to replace the old ones on the various boards. 

Dillen wrote:

Very nice.
MKS is probably not the worst choice here, but I really would have chosen tantals for the two in the remote receiver amplifier.
B&O chose to use tantals here for a reason.
We talked about tantalum capacitors vs. electrolytics in a thread here some time ago, but I can't seem to find it right now.

EDIT:
Found it

link

Martin

WOW!  Thanks a lot for that Martin!  However I always fitted tantals where tantals where used before except for the signal path where I would replace them with films and I will certainly rectify that.  But to add you your outstanding tantal application 101, I do not hesitate to replace other type of capacitors around IC's and controllers with tantals to keep those chips healthy and stable (depending on their purpose of course).  I've seen a lot of people here replacing tantals on the FM circuit boards of the reputable BM4400 with electrolytics and I believe this is a bad pratice.  Thanks again!

Quick update: I finally found some time to work on the Beomaster and continued with the replacement of the reservoir caps. As I don't have a 3D printer I had to come up with another way to secure the capacitors (the new caps are considerably smaller compared to the old ones). At my local hardware store I found some thin walled PP tubing that fit in the cap holders rather nicely. Here are the 4 sleeves cut to size.

New vs. old

Here are the new caps installed in the chassis.

Looks great. Nice work.

-sonavor

The plan is now to connect all boards and do a power up test. However, it looks like someone made an 'improvement' to the preamplifier and tone control board. First of all the filter out and filter in RCAs have been bypassed with jumper wires on the preamp board connector.  

From the RCA panel a cable is connected to the tone control board (I assume with the purpose of a PRE-IN without the need of U-cables).  

Here's the connection to the backside of the tone control board (P24).