RasmusOe wrote:
I have a question regarding replacemnet of capacitors.
Would any capacitor with the right capacitance, voltage rates and heat rates be good enough? Are there other factors i have to consider?
You can run into some heated arguments on the audio forums when it comes to capacitor replacement. These 400x series turntables are all around 40+ years old. There are a number of electrolytic type capacitors that are likely near the end of their life. However, in my repairs, most of the capacitors tested out good. I still usually replace them though because I already have the units open for restoration and I don't want to go back in later. On the small, red, teardrop type capacitors (the tantalums), only a couple of those were out of tolerance. Beoworld member Menahem and some others like replacing those smaller value caps with WIMA polyester caps (non-polar). Other Beoworld members will argue the tantalums should be left alone or (if out of tolerance), replaced with new tantalums. You will find arguments for both options. When in doubt, you can't go wrong by replacing the old component with a new equivalent. The original engineers knew what they were doing so matching what they originally chose is always a good choice I think. On these 400x turntables though, I do like changing the smaller caps out with non-polar WIMA polyesters.
About voltage and polarity - You can't go down in voltage rating but you can go up. I generally try to match the existing voltage rating if I can. The tantalums and most of the electrolytic capacitors are polarized so you have to mount those in the correct direction. Be careful though, a few electrolytic caps in the circuit might be non-polar type so the replacement must also be non-polar.
Other factors about the electrolytic replacement capacitors are the characteristics of the type. Manufacturers sell special, audio rated caps as well as caps for other characteristics. In the Beogram 4002 turntable, none of the caps are in the audio signal path. The turntable audio signal goes from the cartridge and out of the turntable through a muting relay. No other circuitry is involved unless you have a Beogram 6000 with the on-board RIAA amplifier. For my 4002 restorations I didn't use any audio quality electrolytic caps (unless they were a good fit physically). I used some Nichicon (BT, PW, etc) and Panasonic FM types looking for high reliability and low impedance.
Another factor in the restoration is the physical size of the replacement component.