Impedance Question?

Why would they not use a higher value capacitor if that improves the sound and provides more pairing options?

1: Cost, the larger uF the more expensive.
2: Size, the larger uF the more real-estate it takes up.
3: The sound deterioration the larger uF you go.

Cheers George


 

Yes that’s if the coupling cap is 5uF that I used as a hypothetical.
If it's 1uf the -3dB is at 16hz. or .47uf the -3db at 32hz

Cheers George

You say your amp this 10kohm, this is the 10000 in the formula, and the 5 is the 5uf cap I said should be the minimum for -3db at 3.18hz bass rolloff.

Cheers George 

Before anyone corrects me on pie, I’m an Aussie we love our beer, meat pie’s/ with blood.

Cheers George

(2 pie x 10kohm x 5uf)

6.28 x 10000 x 5 to the minus 6, = then 1/x (reciprocal) the answer
which equals -3db @ 3.18hz

Cheers George

The Dared apparently has a low input impedance.

Yes as you stated 100ohms in your previous post, which will drive any poweramp.

But being a tube it will be capacitor coupled, and if that cap is not big enough in uF, that 100ohms output impedance can start to rise in the bass and increase that 100ohms, and if it rises enough, into a 10kohm amp you could get bass rolloff.

The cap needs to be at least 5uF into 10kohm, to be rolling off the bass -3db at 3hz which just starting to rolloff at 20hz

This is why direct coupling is so good, no cap to **** things up and to colour the sound.
Best cap is no cap.

Cheers George

toddverrone554 posts09-29-2017 11:50amQuick and dirty answer: you want the amp to have an input impedance at least 10x the output impedance of the pre.

This is a good simple answer.

Cheers George