Yes, I know it should be non-polarized.
I think I will use this:
http://www.elfa.se/elfa-bin/dyndok.pl?lang=no&dok=2012665.htm?_65_471_29
I think I will use this:
http://www.elfa.se/elfa-bin/dyndok.pl?lang=no&dok=2012665.htm?_65_471_29
Hannes, does it really need to be at least 10 µF?
What if I go smaller, what if I go bigger than that?
Calculate it. Z= 1/(2*pi*f*C)
The cap impedance impedance (Zc) forms a potential divider with the load impedance. As the frequency is lowered, Zc can become large enough to audibly affect the frequency and phase response.
Google a reactance calculator to get a feel for Zc at (say) 50Hz and see how this affects your load impedance (your amplifier Zin).
If I May...
Why do you want to replace the output cap? Is there something wrong with it? A coupling cap in that application will have little, if any influence on final sound if it is properly sized. A 10 uF cap into a 10k input impedance will give a 1.6 Hz roll-off frequency, which will keep any voltage drop across the cap to an extremely low value. If there is no voltage drop, there can be no influence on sound. (Woops - I better go put on my flame proof suit, I'm sure many here will disagree )
Substituting a lager value probably will give you nothing, a smaller value will raise the high pass frequency, which could possibly adversly affect sound.
Mike
Why do you want to replace the output cap? Is there something wrong with it? A coupling cap in that application will have little, if any influence on final sound if it is properly sized. A 10 uF cap into a 10k input impedance will give a 1.6 Hz roll-off frequency, which will keep any voltage drop across the cap to an extremely low value. If there is no voltage drop, there can be no influence on sound. (Woops - I better go put on my flame proof suit, I'm sure many here will disagree
)Substituting a lager value probably will give you nothing, a smaller value will raise the high pass frequency, which could possibly adversly affect sound.
Mike
I see no reason for a phono section to have a response to 1.6 Hz. That enables woofer pumping
You may want to try this.....
Coupling Capacitor Calculator by V-Cap
.
You may want to try this.....
Coupling Capacitor Calculator by V-Cap
.
The LF response of the circuit is already limited by a small coupling cap between the gain stages.
From the link I posted:
The higher the capacitor value, the more material in the signal path. The more material in the signal path, well, you know where this is going... the less transparent the signal becomes. When it comes to output coupling caps, less is more, as long as you've achieved a reasonable -3db point.
The higher the capacitor value, the more material in the signal path. The more material in the signal path, well, you know where this is going... the less transparent the signal becomes. When it comes to output coupling caps, less is more, as long as you've achieved a reasonable -3db point.
Maybe the designer of the preamp has reasons for staggering the high-pass poles the way he has?
Thank you very much, guys. 
Glad to read things are similar to what I did expect and
was hoping.
Currently I have a 10 µF M-cap with two ERO KP1832 (not sure, most probably 37 nF) parallel.
Did the calculation and with 5K R of my pre amp the -3 db point is more than sufficient, whether
I stay with 10 µf or I go for 5 µF. On the other hand there might happen some slight roll off in
the 30 - 40 Hz area with the smaller value.
I was guessing if a metal foil type like a KPSn or KP would do any better. The downside would
be it's size and I'd need to go for a smaller value. While knowing about this now I will certainly
stay close to 10 µF. Perhaps two 4.7 or three 3.3 µF KP type might be a worthwhile choice.
I will have to rummage around my spare box.
BTW, did anyone try Os-Cons in analogue circuits? I have some left and would like to give them
a try in the Ono MC section. 220 µF would suit for coupling.
@ BigE: Bear in mind most well sounding capacitors are physically large.
Glad to read things are similar to what I did expect andwas hoping.
Currently I have a 10 µF M-cap with two ERO KP1832 (not sure, most probably 37 nF) parallel.
Did the calculation and with 5K R of my pre amp the -3 db point is more than sufficient, whether
I stay with 10 µf or I go for 5 µF. On the other hand there might happen some slight roll off in
the 30 - 40 Hz area with the smaller value.
I was guessing if a metal foil type like a KPSn or KP would do any better. The downside would
be it's size and I'd need to go for a smaller value. While knowing about this now I will certainly
stay close to 10 µF. Perhaps two 4.7 or three 3.3 µF KP type might be a worthwhile choice.
I will have to rummage around my spare box.
BTW, did anyone try Os-Cons in analogue circuits? I have some left and would like to give them
a try in the Ono MC section. 220 µF would suit for coupling.
@ BigE: Bear in mind most well sounding capacitors are physically large.
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And if you're just figuring this out, perhaps you should let those that know (about the Pearl and coupling caps) give the advice....
To summarize:
The Pearl already has a rumble filter (.2uF/100k ) between the stages (it would be bad design to have it at the output--the filter would change depending on the load?!?)
10uF and the input impedance of the next stage (10k, 50k, 100k) will form a basic high pass filter.
You can use a big polypro (like the pearl PCB), non-polarized electro or polarized electro (if you know what you're doing)
Nelson likes to use Elna Silmic II electro caps as large value coupling caps (Pearl2, active xover, ...) The ouput of the Pearl will be at about half the supply, ~14V dc. In almost all cases any stage after the Pearl will be lower that that (most 0V dc). So you want the negative of the electro facing the output.
See my Pearl 1.5:
http://www.diyaudio.com/forums/anal...l2-pcb-but-havent-started-yet-pearl1-5-a.html
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