Caiman passive output mod revealed

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Originally Posted by MartinT

Since the circuit is completed via your preamp's input circuit you could leave yourself open to large thumps when you play music and the muting relay disengages, charging the capacitors all of a sudden.

This happened to me with some Elna Silmics (which I suspect are leaky) and my power amp went into protection shutdown!

In any case, you shouldn't need such a large value as the corner frequency will be unnecessarily low.

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Ok thanks, I'll stay away from values above 47uF in that case. I just noticed that Parts Connexion had some BG NX series at 6.3V at a reasonable price but the lowest value is 220uF, so I thought I'd double check before I wasted my money. I'm glad I did.

Cheers. :)

My passive mod with Superreg in place of 7805.

http://i73.photobucket.com/albums/i2...sex/Fog003.jpg

Hi!

As I'm not a pro in electronics and try to avoid mistakes ... I have three questions to the experts here:
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1)
As it is not always possible to supply caps with 47µf, is it better to go for caps with smaller values (33µf, 22µf, ...) of higher ones ( 100µf)?
Where would you say is the highest/lowest possible value?
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2)
Someone already mentioned in the thread that any type capable of handling more than 2,5v would be ok. Can this be confirmed?
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3)
When using the passive output mod, does it still make sense to upgrade BOTH regs (eg. with muratas)? Or is the replacement of one of the regs 'obsolete' as there is no output opamp to supply?

Thanks, cheers and happy cap-hunting!
cz

1. - 33uF or 22uF will do. The lower you go, the less bass will be had.
2. - 6.3V minimum.
3. - just upgrade the 5V reg.

Thanks Stan, now I know what to hunt for ... ;-)
Cheers, cz

Elna Silmic II - 47uF 10V

• Clean, low distortion. Not the most transparent. Light bass. Leaky - caused power amp to go into protection!

Nichicon Muse bipolar - 47uF 16V

• Nice clean mid, very clean, slightly light bass

Nichicon Muse KZ - 47uF 25V

• Very promising, delicate and clean midrange, extended detailed treble, extended but neutral bass

Rubycon CE bipolar 47uF 16V

• Good clean midrange, less forward than KZ, full bass but not quite as extended

So far it's between the KZ and the Rubycon so I'll put more hours on them both. More caps to come...

Is it really neccessary to use 47uf. In other passive mods I have done I have used nothing bigger than 4.7uf?

It all depends on the input impedance of the next stage, be that preamp or integrated.

Quote:

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Originally Posted by Peter Galbavy

tried a pair of Capxon (?) ones

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Capxon are nasty Chinese capacitors with a poor reputation for leaking and blowing their safety vents. Avoid.

Quote:

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Originally Posted by Puffin

Is it really neccessary to use 47uf. In other passive mods I have done I have used nothing bigger than 4.7uf?

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In the Caiman 10uF is the lowest I recommend.