Hi everyone,
New here and looking for schematics for my most recent purchase, a soundstream ref. 404s. I had no luck googling for it.
Hoping to find the cousin of a friend of somebody's sister that has it lying around in the bottom of a drawer somewhere. PDF will do though.
Also advice wanted on recapping and what to look for in replacement capacitors. For my Rubicon amps I ordered mostly Nichicon FG, KW and KT series and Panasonic FC and FM. Was that a wise thing to do or is there more to a good match with a certain amplifier?
New here and looking for schematics for my most recent purchase, a soundstream ref. 404s. I had no luck googling for it.
Hoping to find the cousin of a friend of somebody's sister that has it lying around in the bottom of a drawer somewhere. PDF will do though.
Also advice wanted on recapping and what to look for in replacement capacitors. For my Rubicon amps I ordered mostly Nichicon FG, KW and KT series and Panasonic FC and FM. Was that a wise thing to do or is there more to a good match with a certain amplifier?
See if these help.
Do you have a reason to replace the capacitors? Confirmed out of tolerance? Leaking electrolyte?
Do you have a reason to replace the capacitors? Confirmed out of tolerance? Leaking electrolyte?
Thanks! That was fast.
On the board of one of my amps there was something of a greyish, brown spray around one of the capacitors. Not sure if it actually came out of the cap but then somebody recommended me replacing them anyway since the amp is approaching 30 years.
What's your opinion?
On the board of one of my amps there was something of a greyish, brown spray around one of the capacitors. Not sure if it actually came out of the cap but then somebody recommended me replacing them anyway since the amp is approaching 30 years.
What's your opinion?
In general, I replace capacitors that have leaked, have a history of leaking or are out of tolerance. I don't do full recaps unless the owner knows that it's generally pointless and is willing to pay the time and money for me to do it. For the average amplifiers, it's absolutely pointless.
If the amp is going into storage and has caps to be replaced before being stored, I'll make sure the amp works (if that's important at the time) but will not replace (reinstall new) capacitors that were defective or expected to leak. The bad caps can be pulled and the locations marked (no cap installed) or the replacement capacitor's leads can just barely be inserted into the board and soldered in (leaving the full length of the leads above the board). I don't expect another capacitor plague but why risk it by installing caps that are just going to sit on a shelf and age?
To me, replacing perfectly good caps makes no sense. Replacing old caps because they're old with capacitors that are going to sit on a shelf and age makes no sense, especially if the owner believes old caps are bad.
One more thing, if the amp is to be sold, of course, leaking caps need to be removed, but if there are no caps causing damage, an amp collector may want the amp as original as possible and if there is work to be done, they may want to do it themselves to make sure it was done properly. They may have a specific make/model of capacitor that they want in various locations (audio, power...) and will have to redo any work that had previously be done. They especially don't want a board that some hack has damaged multiple vias on because the caps were hard to remove. It's also possible that the person replacing the caps didn't clean the board of electrolyte well enough (can be difficult) and those shiny new caps are hiding an area of the board were damage is ongoing.
Too much opinion?
If the amp is going into storage and has caps to be replaced before being stored, I'll make sure the amp works (if that's important at the time) but will not replace (reinstall new) capacitors that were defective or expected to leak. The bad caps can be pulled and the locations marked (no cap installed) or the replacement capacitor's leads can just barely be inserted into the board and soldered in (leaving the full length of the leads above the board). I don't expect another capacitor plague but why risk it by installing caps that are just going to sit on a shelf and age?
To me, replacing perfectly good caps makes no sense. Replacing old caps because they're old with capacitors that are going to sit on a shelf and age makes no sense, especially if the owner believes old caps are bad.
One more thing, if the amp is to be sold, of course, leaking caps need to be removed, but if there are no caps causing damage, an amp collector may want the amp as original as possible and if there is work to be done, they may want to do it themselves to make sure it was done properly. They may have a specific make/model of capacitor that they want in various locations (audio, power...) and will have to redo any work that had previously be done. They especially don't want a board that some hack has damaged multiple vias on because the caps were hard to remove. It's also possible that the person replacing the caps didn't clean the board of electrolyte well enough (can be difficult) and those shiny new caps are hiding an area of the board were damage is ongoing.
Too much opinion?
Wait, did you just call me a hack? 😉
What you're saying sounds sensible.
What about faulty capacitors? Is it okay to measure them while on the board?
What you're saying sounds sensible.
What about faulty capacitors? Is it okay to measure them while on the board?
Measuring in the circuit is typically unreliable.
You should never damage vias (if that's what you're referring to). You can add new solder, desolder and then add new solder again, then desolder one terminal at a time by heating one pad and rocking the cap away from it. Alternate terminals/pads until the cap it out.
ChipQuik is an alternative that can help. Whth ChipQuik, you would do as above but when you add new solder the second time it would be the ChipQuik.
For snap-mount caps, you will need to push the terminal away from the walls of the via then desolder. Either of the above techniques will work.
While I haven't done it often, for smaller caps, some people simply rock the cap back and forth to break the terminals loose inside the cap then pull the cap off of its leads. This is sometimes a viable solution when there is a huge trace or copper pour on the top of the board and it's very nearly impossible to get enough heat through the via to heat all of the solder. Others should comment if they have used this method of removing caps and their success/failure rates.
You should never damage vias (if that's what you're referring to). You can add new solder, desolder and then add new solder again, then desolder one terminal at a time by heating one pad and rocking the cap away from it. Alternate terminals/pads until the cap it out.
ChipQuik is an alternative that can help. Whth ChipQuik, you would do as above but when you add new solder the second time it would be the ChipQuik.
For snap-mount caps, you will need to push the terminal away from the walls of the via then desolder. Either of the above techniques will work.
While I haven't done it often, for smaller caps, some people simply rock the cap back and forth to break the terminals loose inside the cap then pull the cap off of its leads. This is sometimes a viable solution when there is a huge trace or copper pour on the top of the board and it's very nearly impossible to get enough heat through the via to heat all of the solder. Others should comment if they have used this method of removing caps and their success/failure rates.