Spica TC-50i crossover recap values

[Lucas the cat]

I’ve recently been able to setup my ancient stereo after eleven years of storage, and found my Spica speakers sounded poor. I’ve removed the crossovers and found these readings on the electrolytic capacitors installed.

Here are my readings, with labeled value first, speaker A then speaker B:
C1 - Labeled 4.7mfd, 8.2mfd and 6.25mfd
C2 - Labeled 4.7mfd, 5.94mfd and 8.54mfd
C4 - Labeled 40mfd, 46.5mfd and 46.2mfd
C7 - Labeled 3.1mfd, 5.5mfd and 3.65mfd
C8 - Labeled 4.7mfd, 9.47mfd and 6.18mfd

Can anyone suggest better values for a H4.0-11 board since none of these values seem usable?

[AllenB]

It might be best to start with the original values. 4.7uF is easy to find, 39uF will do for C4, and 3.3uF would be a good start for C7.

[Lucas the cat]

Thanks for the suggestion, but the original builder/designer/manufacturer was a clever individual who reportedly mixed and matched the tolerances to suit his purposes, as the label had a 10% or 20% tolerance. My readings are obviously past some of those values, so I'm off the map as far as what the designer was after.

At this point I plan to install replacement polypropylenes with the labeled values and and sort out the repercussions.

[tinitus]

found this site

Spica TC-50 Crossover Schematics | Repair, by the Spica Enthusiast

[Lucas the cat]

Had to relocate capacitor C5 to make room for the 40mfd C4 capacitor. Added 1 ohm to the summed woofer notch filter and .5 ohm to tweeter filter. Attached is a picture of the front side of the board.

The initial impression is it sounds likes speakers, no longer like running a rifle brush into my ear, which is good. Before the recap they sounded terrible. Nice to have the speakers back in service.

[bassnkeys]

Question.
I need to recap my TC-50's. John Bau said that the caps were installed after measuring and did not necessarily match the exact value printed on them by the manufacturer. If mine are old but still working will they measure the same value as when installed by Spica?
Thanks.

[Lucas the cat]

Mine measured way out of labeled value with a Fluke 189 DC multimeter. I ended up punting and replacing them by equivalent labeled value polypropylene Dayton capacitors from Parts Express. With the size of the circuit board it was very easy. Search my name without spaces and you will find a thread on another board with my notes.

Before they made everything sound bad, mostly unlistenable. After the recap I like them a lot, and find myself listening to a lot of music for details I hadn't heard before. (I have an old system and went through the whole setup cleaning all connections too. I don't have any other systems to compare to, so my results are highly subjective.)