BoSoZ C1, C2 film caps

[2Bak]

Should the C1 and C2 film caps in line stage be exactly 10uF?
Could I experiment with lower capacitances at C1, C2, e.g. 4,7uf, 680 v MCAP Supremes? If so should I change anything else?

Thanks
Jan Bak Madsen

 

[mpopovics]

4u7 caps

You can paralel two caps. On that way you get close to 10uF value.
But you can play with lower values too.

BR,

 

[ralf]

sounds diffrent with lower capacitance?

Hi, i?m building my bosoz too.
i used 10uF Siemens MKV (very expensive)

It would be interesting, if someone has experiences in differences in Sound, when using smaller Coupling-Capacitors.???

Ralf

 

[GRollins]

Smaller caps will cause the low end to roll off at higher and higher frequencies. It's up to you how far you will want to take it.

Grey

 

[Peter Daniel]

...and it's also dependant on the input impedance of the amp conected to the preamp (and a cap itself).

For a 6dB per octave high pass filter:
F= 1 / 2 x Pi x R x C where
F= -3dB frequency in Hz, R=amp inp resistance in ohms
C=Capacitance in Farads, Pi=3.1415926

You do the math and another mystery in DIY solved😉

 

[Nelson Pass]

You must add the resistance of the Drain resistors of
the Mosfets going off to the positive supply to the input
impedance of the amp to get the exact value of R.

 

[Super_BQ]

C1 & C2

I used Solen polypropylene caps 10uF rated at 400V for my BoSoZ. They were not expensive and thought the upgrade was worth while. Electrolytics can be nasty in the signal paths.

BQ