Are Mundorfs better ?

[Alvolake]

2 of the 4 output caps on my 8 year old amp are swollen so I´m going to change them. I can get 10,000uF, 50v 105º Jackon ´lytics just down the road but a mate recommends I buy some Mundorf m-Lytic AG 63v which cost 4 times as much. It´s a Class A amp so gets pretty hot and the quiescent current is 46v . How much more is 63v than 50v in terms of real world longevity ?

 

[reddish75]

Are they screw terminals or snapin's?

Also quiescent current 46v? Current's not measured in volts, what do you mean by this?

If the amplifier is the A21se as in your profile I would guess the 46v is the d.c voltage your powersupply is making when the amplifier is idling. The 10000uf cap's will be the powersupply resivoir capacitors not output capacitors which if true would make 20000uf output capacitors per channel something never seen in a commercial amplifier.

My advice take, it to a shop to get the repair done before it gets ruined, as no offence but reading your first post, you don't know much about electronics.

 

[Alvolake]

No offence taken, chaps. You are quite right i am not even a beginner at electronics. I am simply repeating what my engineer mate said to me in Spanish. The "quiescent" bit was mine, he actually said "voltage at rest" in Spanish which I now realise means when idling. It is indeed an A21SE and the caps are the type which have two leads about a centimetre apart which thread through the board to be soldered. There are 2 large caps on each board, one is a "filter" -the ones that definitely look swollen and badly treated - and the other is the output cap or so I understood and they are all of the same make and value, namely Eurocaps 10,000uF, 50v, 85º. Shall I fit the Panasonics or go for the Mundorfs - I have to send away for 4 of either of them so it´ll be the Jackons meanwhile.

many thanks for your replies ( and concern).

P.S. I don´t mind forking out for the Mundorfs if they are better even if only from a security/life point of view. By the time they get here (Canary I)slands) , costs (transport and duties) will be more, relatively speaking, then their actual cost.

 

[reddish75]

Panasonic Tsha, found here http://uk.mouser.com/ProductDetail/Panasonic-Electronic-Components/ECO-S1JA103EA/?qs=sGAEpiMZZMtZ1n0r9vR22RSFeKT%2fCuZ6wqTwgzC2iWo%3d, great work horse industry standard caps rated at 105oc 63v, better to go for 63v rather than 50v as there is supposed to be a + 10% gap between rated voltage and actual voltage, however with varying mains voltages your dc rails can be upto ~ 2-3 volts higher than specified also some company's sale close to the wind on their component ratings.

If there are output capacitors, I haven't looked at the schematic for a long time with that amp and it hasn't already got them instruct your tech to install 0.1uf wima mks2 or mks4 poly caps accross the pins of the output caps.

Make sure you specify when your tech knows exactly what you want also get him to check and adjust the bias current while its in for repair ( this should be a given but often doesn't happen).

Also just a thought if there are more poor quality Jelly bean capacitors in there maybe it'll be prudent to get them all replaced, in this case the panasonic fm/fc/fr range are the ones to go for.

 

[bmtell]

If it was me I'd go for the Panasonics and see if 63v 105 deg ones would fit. The 50v 85 deg ones will work happily though.

 

[i_should_coco]

I've always liked he TS-HA.

 

[Alvolake]

I don´t have the schematic- it´s not in the manual, unlike my old A48II, and we don´t know what the bias current should read. I´ll have to phone Suggies tomorrow.

 

[zucco]

Panasonic Tsha, found here http://uk.mouser.com/ProductDetail/Panasonic-Electronic-Components/ECO-S1JA103EA/?qs=sGAEpiMZZMtZ1n0r9vR22RSFeKT%2fCuZ6wqTwgzC2iWo%3d, great work horse industry standard caps rated at 105oc 63v, better to go for 63v rather than 50v as there is supposed to be a + 10% gap between rated voltage and actual voltage, however with varying mains voltages your dc rails can be upto ~ 2-3 volts higher than specified also some company's sale close to the wind on their component ratings.If there are output capacitors, I haven't looked at the schematic for a long time with that amp and it hasn't already got them instruct your tech to install 0.1uf wima mks2 or mks4 poly caps accross the pins of the output caps.

Make sure you specify when your tech knows exactly what you want also get him to check and adjust the bias current while its in for repair ( this should be a given but often doesn't happen).

Also just a thought if there are more poor quality Jelly bean capacitors in there maybe it'll be prudent to get them all replaced, in this case the panasonic fm/fc/fr range are the ones to go for.

Very good advice! FMs very well spec'd, poly by-passes always worthwhile, also I've had fantastic results upgrading my Avondale amps with Mcaps.

 

[Alvolake]

By Mcaps , do you mean Mundorf caps ?

 

[Alvolake]

Panasonic Tsha, found here http://uk.mouser.com/ProductDetail/Panasonic-Electronic-Components/ECO-S1JA103EA/?qs=sGAEpiMZZMtZ1n0r9vR22RSFeKT%2fCuZ6wqTwgzC2iWo%3d, great work horse industry standard caps rated at 105oc 63v, better to go for 63v rather than 50v as there is supposed to be a + 10% gap between rated voltage and actual voltage, however with varying mains voltages your dc rails can be upto ~ 2-3 volts higher than specified also some company's sale close to the wind on their component ratings.If there are output capacitors, I haven't looked at the schematic for a long time with that amp and it hasn't already got them instruct your tech to install 0.1uf wima mks2 or mks4 poly caps accross the pins of the output caps.

Make sure you specify when your tech knows exactly what you want also get him to check and adjust the bias current while its in for repair ( this should be a given but often doesn't happen).

Also just a thought if there are more poor quality Jelly bean capacitors in there maybe it'll be prudent to get them all replaced, in this case the panasonic fm/fc/fr range are the ones to go for.

It took a while but the Panasonic TS-HA caps are now in place. All seems to be in order and quiet. This weekend I´ll give it a whirl.

Can someone explain the bit about placing 0.1uF wimas across the output caps pins. I happen to have a couple of o.1uF FT2 Russian teflon caps right now - might they do, assuming I can make them fit ?

 

[taff]

I'm sure someone more knowledgeable will comment but I think bypassing with a small cap lets more detail through without bypassing totally therefore risking DC going to the speakers.. also cheaper than using ££ caps for output caps to get a good clean output (I think.. happy to be corrected!)

 

[reddish75]

The reason we bypass large electrolytic capacitors with film caps such as wima's etc is that the large capacitors cannot handle radio/high frequency noise, without this 'filter' it just passes this onto the next part of the circuit, the film capacitors give this 'noise' an alternative route thus filtering this noise out.

That's the best I can explain it half cocked.