Hi Everyone, I have bought an older NAD C272 and I want to replace the old capacitor (10000uf 80V) that has 4 pcs in total but there is space for 6 pcs on the motherboard, anyone who can see if it would be a good idea to put 6 10000uf 80v in it? think this one type 383LX103M080A082 Cornell Dubilier Electronics (CDE) | Capacitors | DigiKey
Is the capacitor good? or is there a better type for the purpose? I have not been able to find others that can be used. max Dim.35mm height max 95-100mm
attaches service chart link
NAD C272 - Manual - Stereo Power Amplifier - HiFi Engine
Is the capacitor good? or is there a better type for the purpose? I have not been able to find others that can be used. max Dim.35mm height max 95-100mm
attaches service chart link
NAD C272 - Manual - Stereo Power Amplifier - HiFi Engine
Attachments
In early production NAD used JH (Jianghai) CD294 series 10,000uF 80V capacitors, white in color. They were poor quality and failed often. I had to replace them in my C372 because they shorted and blew the line fuse. I would recommend that the JH white capacitors be replaced on sight.
But from your picture your amp has updated capacitors that may not need replacing. Do they measure in spec for capacitance and ESR?
Certainly you can add a third pair of 10,000uF capacitors but I wouldn't expect a large improvement. The bass might get a little firmer with the extra capacitance.
The CDE capacitors you found are good components and would be suitable for use in the C272.
But from your picture your amp has updated capacitors that may not need replacing. Do they measure in spec for capacitance and ESR?
Certainly you can add a third pair of 10,000uF capacitors but I wouldn't expect a large improvement. The bass might get a little firmer with the extra capacitance.
The CDE capacitors you found are good components and would be suitable for use in the C272.
Hi Bill_P,
I do not have the necessary knowledge whether the capacitors are ok or not, just read that there were several amplifiers where they were broken, so i think better safe than sorry
they are not so expensive they capacitor anyway.
I will try to mount 6x10000uf which I linked to in the first post, now that space for the 2 extra has been allocated on the board.
Thanks for your help.
Do you have any other ideas that could improve your amplifier?
I do not have the necessary knowledge whether the capacitors are ok or not, just read that there were several amplifiers where they were broken, so i think better safe than sorry
they are not so expensive they capacitor anyway.I will try to mount 6x10000uf which I linked to in the first post, now that space for the 2 extra has been allocated on the board.
Thanks for your help.
Do you have any other ideas that could improve your amplifier?
The thing is, these units are not old old. In consumer power amps that were in regular domestic use (rather than being thrashed like PA amps), these big filter caps tend to last a very long time, and recapping rarely is needed before they're 25-30 years old - garbage parts obviously excepted. If NAD got burned on the first run, it is to be hoped that they were smart enough to switch to some substantially better-quality caps. 6 vs. 4 caps is also falling into diminishing returns territory... 2x 20000 µF is a more than decent amount of capacitance to begin with.
As a rough indication, I would
a) listen for audible hum out of the speakers
b) connect a multimeter with a low-voltage AC mode to the main + and - supplies (e.g. on the big caps) and a central ground point somewhere. (Ideally you have something to clip your ground lead onto, so that one-handed probing of +B/-B points can be carried out without undue risk of shorting something.) @ no output: <1 Vrms = good, >3 Vrms = bad.
As a rough indication, I would
a) listen for audible hum out of the speakers
b) connect a multimeter with a low-voltage AC mode to the main + and - supplies (e.g. on the big caps) and a central ground point somewhere. (Ideally you have something to clip your ground lead onto, so that one-handed probing of +B/-B points can be carried out without undue risk of shorting something.) @ no output: <1 Vrms = good, >3 Vrms = bad.
hi, i ordered the parts from digikey and in just 2 days the parts were delivered USA-Denmark pretty well anyway
I have changed the parts in Nad C272 today and it is quite easy as it is module built, I have replaced the 4 pieces 10000uf with 6 new ones so now there are 60000uf against 40000uf so all slots are filled now, I also have changed a larger part of the other capacitor though not all as I do not have everyone at home, but it plays fine now and there is less noise than before so now it would like to work some years again.
Otherwise, any modification that could get the sound a class up on it?
I have changed the parts in Nad C272 today and it is quite easy as it is module built, I have replaced the 4 pieces 10000uf with 6 new ones so now there are 60000uf against 40000uf so all slots are filled now, I also have changed a larger part of the other capacitor though not all as I do not have everyone at home, but it plays fine now and there is less noise than before so now it would like to work some years again.
Otherwise, any modification that could get the sound a class up on it?
I'd be concerned about the greater in-rush current pull now that you have increased capacitance by 20,000uf. It is a common upgrade in the NAD 214 to add two extra filter caps in the empty slots on the board (which populate the almost identical 216), but in that case, you are only increasing capacitance by 4700uf X2. I have the C270 which is very similar to the C272 and just stuck with four main filter caps. I also chose Cornell Dubillier.
Did you choose 4x10000uf/80v?
I have a Nad 216 with 4x12000uf/80v (nippon smh-series) and have been working fine for 2 yrs now. There it’s about 19000uf over original.
While I see no problem with more filtering, it does beg a question...
Have you gentlemen considered the extra strain on the power supply, particularly rectifier bridges and transformers when turning these modified systems on?
That first couple of cycles of AC is pretty heavy and by doubling or quadrupling the capacitor load you are doubling or quadrupling that initial inrush of current. I'm not saying it will, but it could shorten the life of your bridge and transformer quite noticeably.
I agree with you. I recommend staying with 40,000uf of total filtering and not upping that to 60,000uf.
My take is: 8 ohm loads: one pair of caps would be fine, 4 ohm loads: 2 pairs, 2 ohms: 3 pairs. Bunging more in that needed isn't intelligent or thrifty, with the possible exception of being able to use lower ripple-current rated caps if you have more of them, but that doesn't mean you need the extra capacitance. Usually 10mF is plenty for an 8 ohm amp.
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