Repair active subwoofers - Weird cap value and size

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Hello everybody, I just joined this forum as it is now of my interest to learn more about electronics and especially audio gear.
I'm also active in some other forum on DIY synth making and posted these questions on another more general forum.
Please let me know if it is not the place to post and ask for this kind of help and input, I'll delete the thread.

I underwent the dismantling of a set of two subs: the Nova IN 15 SUB.
It is composed of an active sub with an amplifying module inside and I started to open this module after the sub started to me unresponsive to incoming signal.

What I discovered is not so unusual: a bunch of pretty bad, blown caps.

Now I wanted to start this repair by switching these bad caps to new caps but I stumbled upon some weird values and size.

They are big 25mmx50mm 2200uF 125V electrolytic caps.
I found out that this value of caps could not be found in 125V (really odd rating) and the only ones available in 200V are 10mm larger so would not fit on the board.

I have not investigated yet what their role is on the board, if it is power supply related or audio filtering related so I thought some of you guys would have a better guess than me.

I could theoretically solder bigger caps and glue the crap out of them on the board, but i'd rather not do that on such vibrating and sensitive equipment.

I emailed the manufacturers but they refused to send the schematics or a service manuel to me and just proposed that I ship the unit (expensive process i believe).

So, do some of you already stumbled across this kind of odd value?
Could these caps be replaced with other more common value?

Thanks a lot for you help and your time,

best,

JJanus
 

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Hello everybody, I just joined this forum as it is now of my interest to learn more about electronics and especially audio gear.
I'm also active in some other forum on DIY synth making and posted these questions on another more general forum.
Please let me know if it is not the place to post and ask for this kind of help and input, I'll delete the thread.

I underwent the dismantling of a set of two subs: the Nova IN 15 SUB.
It is composed of an active sub with an amplifying module inside and I started to open this module after the sub started to me unresponsive to incoming signal.

What I discovered is not so unusual: a bunch of pretty bad, blown caps.

Now I wanted to start this repair by switching these bad caps to new caps but I stumbled upon some weird values and size.

They are big 25mmx50mm 2200uF 125V electrolytic caps.
I found out that this value of caps could not be found in 125V (really odd rating) and the only ones available in 200V are 10mm larger so would not fit on the board.

I have not investigated yet what their role is on the board, if it is power supply related or audio filtering related so I thought some of you guys would have a better guess than me.

I could theoretically solder bigger caps and glue the crap out of them on the board, but i'd rather not do that on such vibrating and sensitive equipment.

I emailed the manufacturers but they refused to send the schematics or a service manuel to me and just proposed that I ship the unit (expensive process i believe).

So, do some of you already stumbled across this kind of odd value?
Could these caps be replaced with other more common value?

Thanks a lot for you help and your time,

best,

JJanus
of cours you can use it same capacity and save voltage to use and you can add short wires for fitting it
 
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What kind of caps? If electrolytic, their exact value rarely matters and by a wide margin. Best to err on the up side in capacitance and voltage. But that should be easy with more modern caps.

But take care about polarities or if non-polarized caps are in there.
 
To get a general idea of how such a supply is constructed, take a look at the schematic of a Behringer NU3000, which can be found online.
Based on the location of the caps on the circuit board and their value, I think they smooth the voltage on the power rails at the secondary side of the SMPS transformer. These must be designed for SMPS power supplies, as their low ESR is important. For a good life expectancy, a 105 deg C rating is preferred. It's a 1000 W / 8 ohm amplifier, probably running in bridge-tied-load mode, which means that the power supply voltages will be around + and - 70 Vdc.
 
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Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.