PSU capacitor replacement for Marantz MA-500 mono amps

[SimontY]

Hi all,

In one of my Marantz MA500 mono-block power amps, the original caps have started to bulge and leak slightly.

They are Elna for Audio, 71V 10,000uF 55m Height x 30mm Diameter.

The voltage rails measure 62V or so.

Can anyone suggest a good quality replacement? I'd like to keep it under £15 per cap (i.e. <£60 total to make both amps the same).

Someone can sell me some Cornell Dubiler 12,000uF / 80V for £8 each that will fit with a little drilling/persuasion.

I've been looking around and see that Kendeil, BHC/Aerovox, BC components, Siemens Sikorel, Elna Cerafine or Silmic all come recommended by various people. But finding caps the size and voltage I need that will actually fit and be cheap enough seems an impossible task.

So I'm asking for your advice.

Thanks,
Simon

 

[jaycee]

Cornell Dubilier is a good make, and that's a good price. They should work very well.

A simple mod would be to get some good quality 100-470nF capacitors and solder those across the large electrolytics to improve high frequency response, but the marantz probably already has this.

 

[SimontY]

Cornell Dubilier is a good make, and that's a good price. They should work very well.

A simple mod would be to get some good quality 100-470nF capacitors and solder those across the large electrolytics to improve high frequency response, but the marantz probably already has this.

Thanks for your helpful reply. I did search about the Cornell caps and now, of course, I realise I misspelled

 

[SimontY]

Cornell Dubilier is a good make, and that's a good price. They should work very well.

A simple mod would be to get some good quality 100-470nF capacitors and solder those across the large electrolytics to improve high frequency response, but the marantz probably already has this.

Thanks for your helpful reply. I did search about the Cornell caps and now, of course, I realise I misspelled Dubilier. No wonder not much came up.

I may well go with this option, as the price seems quite good. I'd not be happy about using such a small bypass cap, but might opt for something a bit larger, depending on what can be shoehorned in!

Cheers,
Simon

 

[jaycee]

The idea of the small bypass caps is that they are good at high frequency, where electrolytics generally suck.

If you REALLY wanted to go at it, youd have the big caps, a small electrolytic say 220uF-470uF, and then the 100nF-470nF capacitors, but that is pushing it for space. In this situation, putting some high quality 470nF capacitors across the terminals of the big electrolytics works very well, and is easy to do in a tight space.

 

[auriches]

The idea of the small bypass caps is that they are good at high frequency, where electrolytics generally suck.

If you REALLY wanted to go at it, youd have the big caps, a small electrolytic say 220uF-470uF, and then the 100nF-470nF capacitors, but that is pushing it for space. In this situation, putting some high quality 470nF capacitors across the terminals of the big electrolytics works very well, and is easy to do in a tight space.

Hi,

how often is this done in commercial amps by the manufacturers? i see a lot of diy'ers recommending this compulsory but in lots of the gear that i've opened up, this isn't often done? is this simply a cost issue?

i've also read here in another thread that >100u should be used?

what's everyone's comment on this?

sorry for asking noob questions...

 

[SimontY]

Hi,

how often is this done in commercial amps by the manufacturers? i see a lot of diy'ers recommending this compulsory but in lots of the gear that i've opened up, this isn't often done? is this simply a cost issue?

i've also read here in another thread that >100u should be used?

what's everyone's comment on this?

sorry for asking noob questions...

It appeared to be done in my Roksan Caspian and I believe it's done with larger caps in the Marantz PM66ki. I'm sure it's done in other commercial amps too.

Simon