Hi all, new to the forum here. I am currently getting everything together/setup for installing a sound system in my old W123 Mercedes. I have a McIntosh MX406 HU, Soundstream Reference 604 Amp, and have a variety some old-school MB Quart premium speakers and crossovers incoming. I'm am refurbing everything before install.
Everything works on the Soundstream amp and it is clean inside (except for some discolration around the power chokes, but amp has been bench-tested). However, I am going to be re-capping it. I am having trouble finding replacement caps for the 4 big power caps that are rated at 1000uF and 50VDC. They are currently Nichicon VS-series (cannot find datasheet regarding these anywhere) and 20mm diameter x 15mm height. The big issue is the height! I can go a little taller than 15mm, but not much as there is no clearance beyond ~19mm. I cannot find any caps to fit these specs - all seem to be 20mm, 25mm, or 31.5mm tall which will be too tall. Does anyone know of a current cap that will fit these physical restraints for this purpose?
Thanks,
Allen
Everything works on the Soundstream amp and it is clean inside (except for some discolration around the power chokes, but amp has been bench-tested). However, I am going to be re-capping it. I am having trouble finding replacement caps for the 4 big power caps that are rated at 1000uF and 50VDC. They are currently Nichicon VS-series (cannot find datasheet regarding these anywhere) and 20mm diameter x 15mm height. The big issue is the height! I can go a little taller than 15mm, but not much as there is no clearance beyond ~19mm. I cannot find any caps to fit these specs - all seem to be 20mm, 25mm, or 31.5mm tall which will be too tall. Does anyone know of a current cap that will fit these physical restraints for this purpose?
Thanks,
Allen
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Recapping is typically pointless unless you know that there is a problem with the capacitors. Check their value. If they're within tolerance and not leaking electrolyte, replacing them will make no difference.
Nichicon are good, replacements may not be same high quality.
Agree with rayma, and Perry, no need to replace unless really essential.
If you do need to, see 35V series, they should be good enough in a 12V circuit.
Agree with rayma, and Perry, no need to replace unless really essential.
If you do need to, see 35V series, they should be good enough in a 12V circuit.
2200uF/63V is 18mm dia and 31.5mm long from Keltron, which is a Sprague licensee in India.
Circuit permitting, fit two sideways, in place of 4?
They look OK in the photo, just bear this tip in mind if you have a problem like this somewhere else.
Circuit permitting, fit two sideways, in place of 4?
They look OK in the photo, just bear this tip in mind if you have a problem like this somewhere else.
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I have a 1986 Nakamich PA300ll that has been working very well with the original Nichicon capacitors, again, not worth the time and risk of damage.
The MB Quart crossovers might have some capacitors with drifting values however, I would focus more on those. And finding some better tweeters than the MB Quart…
The MB Quart crossovers might have some capacitors with drifting values however, I would focus more on those. And finding some better tweeters than the MB Quart…
I'd like to know how many perfectly good capacitors were replaced with 'capacitor plague' capacitors which will end up causing damage where there was no risk of damage.
If you are convinced that the capacitors are at fault, get a capacitance meter, the graphic types are really low in price.
And check them in circuit, too much risk in removing and putting parts in place. Can damage tracks, for one.
The amp is high powered, I don't think it will be safe to use at full output, so do not worry about the opinion of internet posters...low ESR caps are needed in switching supplies, above 200 kHz, not in analog audio circuits.
Most of those people know little about circuit design and parts selection.
There was indeed a capacitor plague, somebody stole an experimental formula, and it was used in Taiwanese and Chinese electrolytic capacitors, not in Japanese parts (as far as I know), so please leave all the caps in place until you have a fault.
Another thing is that they may need time to reform if the unit was not in use, so let it run for a week at an hour or two daily, see after that.
And check them in circuit, too much risk in removing and putting parts in place. Can damage tracks, for one.
The amp is high powered, I don't think it will be safe to use at full output, so do not worry about the opinion of internet posters...low ESR caps are needed in switching supplies, above 200 kHz, not in analog audio circuits.
Most of those people know little about circuit design and parts selection.
There was indeed a capacitor plague, somebody stole an experimental formula, and it was used in Taiwanese and Chinese electrolytic capacitors, not in Japanese parts (as far as I know), so please leave all the caps in place until you have a fault.
Another thing is that they may need time to reform if the unit was not in use, so let it run for a week at an hour or two daily, see after that.
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Wow, thanks for all the quick replys on this. It is not my intent to hash the old replace/not replace debate. I was simply providing a little background on what I was currently working on as an introduction, being my first post.
I will say that this is a 30year old amp w/ electrolytics and my viewpoint is to replace the caps in this particular instance as a preventative measure. Yes they may measure fine now, but that does not mean I couldn't have an issue a few years down the road (no pun intended). I feel I would be better served to replace caps now while everything is out and I'm making sure everything is up to snuff before install. This would simply be to mitigate any potential future issue / prolong the MTBF. By the time I would have them out to accurately measure, my opinion is that I may as well replace with new at that point.
I could possibly lay caps down if needed, but in that case I may just leave those alone at that point. Nichicons are reputable and this is not a case of capacitor-plague hysteria (which these would not be under that anyways).
As a side note on my project (to get slightly off-topic), this is kind of a budget build/simple install and (somewhat) contemporary build. I will have <$1000 into everything when done, including probable under seat powered sub to fill in a little of the lows considering the size constraints in the factory speakers. I am not building custom speaker boxes, etc, but trying to keep it clean, simple, and mostly original looking.
Thanks,
Allen
I will say that this is a 30year old amp w/ electrolytics and my viewpoint is to replace the caps in this particular instance as a preventative measure. Yes they may measure fine now, but that does not mean I couldn't have an issue a few years down the road (no pun intended). I feel I would be better served to replace caps now while everything is out and I'm making sure everything is up to snuff before install. This would simply be to mitigate any potential future issue / prolong the MTBF. By the time I would have them out to accurately measure, my opinion is that I may as well replace with new at that point.
I could possibly lay caps down if needed, but in that case I may just leave those alone at that point. Nichicons are reputable and this is not a case of capacitor-plague hysteria (which these would not be under that anyways).
As a side note on my project (to get slightly off-topic), this is kind of a budget build/simple install and (somewhat) contemporary build. I will have <$1000 into everything when done, including probable under seat powered sub to fill in a little of the lows considering the size constraints in the factory speakers. I am not building custom speaker boxes, etc, but trying to keep it clean, simple, and mostly original looking.
Thanks,
Allen
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There are studies of temperature and working voltage affecting capacitor life.
I have measured less than 5% error on Japanese electrolytic capacitors in a Mitsubishi PLC made in 1992, test was done with a proper capacitance meter in 2018.
The spec is +/- 20%, FYI.
If they stand up to continuous use for more than 20 years in harsh conditions, I got my money's worth.
And I can safely say that they will last a lot longer in a less harsh environment.
So, that depends where you live, whether you park the car in the sun, and so on.
Be aware that several series are made, in different temperature ratings, and different expected life.
Choose them as per the senior members' advice, and your constraints.
I still say leave them alone until essential, you cannot use it at full load in a saloon car.
I have measured less than 5% error on Japanese electrolytic capacitors in a Mitsubishi PLC made in 1992, test was done with a proper capacitance meter in 2018.
The spec is +/- 20%, FYI.
If they stand up to continuous use for more than 20 years in harsh conditions, I got my money's worth.
And I can safely say that they will last a lot longer in a less harsh environment.
So, that depends where you live, whether you park the car in the sun, and so on.
Be aware that several series are made, in different temperature ratings, and different expected life.
Choose them as per the senior members' advice, and your constraints.
I still say leave them alone until essential, you cannot use it at full load in a saloon car.