1820m cap replacement

[JDC2389]

Hey everyone, I have an 1820m and I really want to get rid of a lot of these pesky cheap caps that cause problems. There is a bit of information and an electrical engineer who has posted some tips for replacing caps on this other forum http://www.productionforums.com/view...p=79951#p79951 (this one has a parts list) http://www.productionforums.com/view...10846&start=45 (classd has some interesting input on what to get) I took a bunch of pictures, some of them are too blurry but these should help http://imgur.com/a/pFfFc ok so, I would really appreciate some ideas for caps I should get/improvements that could be made, my dad and I are going to work on this box and get it in order.

[999999999]

Re: 1820m cap replacement

So I don't have to read the whole linked topic, these caps are in the power subcircuits not audio path coupling caps, correct? If so, I'd just get replacements of the appropriate ratings, diameter and lead pitch to match the available space, something like Panasonic FM series from Digikey.

The following link should take you to their selection boxes to pick the specs:
http://search.digikey.com/us/en/cat/...c%20FM&stock=1

If the order stays under 8 oz weight you can use the cheaper USPS shipping option. In other words if the order is over 8 oz but under 16 oz, it can be cheaper shipping to split it up into two orders. Either way shipping takes about the same time (+/- 1 day).

Take some of the tips "classd" wrote in the topic with a grain of salt, the ideas about solder, soldering, and desoldering issues aren't necessarily true without some other problem which is really unrelated. The right technique with any tool counts and will work or the tools (and solder, etc) wouldn't exist. Replacing only a few caps could be done even with century old tools and solder.

[999999999]

Re: 1820m cap replacement

As for other improvements, what did you have in mind? The sky is the limit on something like this, every other year some chip or other component comes along with slightly better specs. Some would be drop in replacements (solder in) and others might need separate daughter boards to adapt them.

For example there's the power regulator ICs, swapping in something with lower noise specs is a theoretical improvement - though you may not hear any audible difference. It seems to have a row of opamps at the analog outputs, swapping those might also help and is more likely to make a small audible difference. Is that difference an improvement? Sometimes yes, sometimes no. There's dozens of tiny electrolytic caps around what I assumed above were the opamps and the DAC chips, all of those could be replaced with higher spec electrolytics or if the circuit requirements don't need a high uF capacitance value, perhaps polymer or film capacitors instead of electrolytic. The cost and time for this will keep rising.

Overall I'm inclined to suggest that you leave the design as-is except replacing some of the electrolytic caps already known to be potentially problematic.