First of all a hello, having recently bought my Polaris!

Whilst it's in great cosmetic condition for its age, a problem with Voice 2 has just developed. As I have little test equipment I swapped chips around between synth voice circuits to find that the CEM3372 chip in Voice 2 was defective. When I put a good chip in the circuit that didn't work either so I think I have a defective chip and a problem in the surrounding circuit. By checking voltages around the pins of the CEM3372 and comparing these with a functioning Voice there are significant differences on pins 17 and 12 i.e. the VCF out / VCA in across one of the 2.2 uF electrolytic capacitors. Consequently I suspect a faulty 2.2 uF cap and plan to replace that tomorrow to see if that does the trick.

Does anyone else have any experience of this kind of problem?

The synth is just shy of 30 years old so I'm wondering what the best advice is regarding replacement of electrolytic caps? I suspect they maybe due to give some problems in the synth voice circuits as I've noticed some slight tuning stability issues along with a slight portamento sometimes ...

If a cap goes can it damage the CEM3372? I'm guessing it can because it looks like that may have happened here! The CEM's are relatively expensive to replace (£35 each on eBay) so I'm wondering if I should re-cap soon ... 

Does anyone know of a good source of CEM3372 chips? I've read that some of the more recent revisions deliver different sound qualities to the older revisions, to the extent that they are not interchangeable. Is there anything in that?

Regards

Mike