Caiman passive output mod revealed

[leo]

Oscons tend to be DC leaky especially the polymer based variety so I'd be cautious using them for coupling, work nice decoupling digital IC's or XO's though.

[Reid Malenfant]

How much worse are they than any standard wet electrolyte electrolytic? I mean they all leak to a certain extent though we should be talking micro Amperes in reality.

Do you happen to know how much worse the solid electrolytics (SEP) are by chance? 10%? 100%? Sorry, i gots to know

Cheers in advance Leo

[MartinT]

Obviously down to personal taste but I've tried both Nichicon FG and SilmicII, I prefer the grey Rubycons over both those .
Its worth trying these different types out yourself though

Agreed, Leo, I also prefer the grey Rubycon CE types, which are still in circuit.

[Gazjam]

Still think the Clarity Caps will better all of those,but YMMV.

Those are next on the list Ali
Hopefully by then curiosity will stop getting the better of me!

[Gazjam]

Agreed, Leo, I also prefer the grey Rubycon CE types, which are still in circuit.

Tried to source some of these, bloomin hard to find!
Are they not being made any more?

I remember there was a group buy from the States to get them for upgrading the opamp board...but that was a while ago.

[Ali Tait]

Aye,at least they are cheap,I've got the SCR's in now,which cost more than the dac!

[Gazjam]

What no Sanyo Os-cons? Actually i'm being serious, Os-cons should sound better than the above as they have a solid electrolyte rather than liquid. Super low ESR over a really wide bandwidth & though it's not relevant a massive ripple current capability.

By the way, don't bother checking out the 47uf 25V KZ Attachment 2457 Go straight for the 50V version as this will give you better performance due to lower losses

Hey Mark,
your comment about the voltage got me thinking...

As there didn't seem to be any concensus about voltages (as opposed to uf) for the caps for this application, and believe me I checked(!), I guess I tried a variety of values as they were just a few pence to buy.

Your comment though about 50v giving better performance due to lower losses...does this apply across the board with all opamps in this case or just the Sanyo solid electrolyte ones you spoke of?

Always keen to learn about this stuff! ...

Going by the different choices of cap made here, I guess like most hifi stuff it comes down to the individuals ears!
Is there a general concensus though about "best voltage" for caps for the passive output mod for the dac?

ta.

[Gazjam]

DP

[Reid Malenfant]

Hi Gaz, it applies to all electrolytics & to a certain extent non electrolytic capacitors The higher the voltage rating of the capacitor the less losses you'll get, less DC leakage current & you'll find that 99% of the time that capacitor ESR (equivalent series resistance) is lower as well.

In a way it's pretty obvious, a capacitor that is designed to have a maximum of say 25V accross it is manufactured to have a leakage current within certain limits. If you substituted one of lets say 4 times the voltage rating but kept the maximum voltage accross it at 25V or less then you'll get much less current leakage as that cap should have been designed to leak about the same as the 25V cap but at 100V

Give it 25V & the leakage current should be 1/4 of the 25V cap...

I'd like to point out that all capacitors should be "formed" or in the case of an older cap, "reformed". This involves something as simple as a regulated power supply set at the maximum voltage of the capacitor & a high value resistor or current regulation to gradually charge the capacitor up before you ever use it. Obviously discharge through another resistor before fitting it into a circuit

Doing this should give you maximum capacitor performance by reducing leakage currents

[Ali Tait]

Easily the best I've tried,but then I'm enjoying the Audio Note coppers in the AN dac too.