Function of Input Capacitor on Orange Rocker 30

[JammyDodger]

Hey All,


Here is a portion of a schematic for an Orange Rocker 30. It seems unusual that there is a capacitor (C27, 0.22uF) at the input. Can anyone tell me what that does?
Is it acting as a highpass filter?

[sluckey]

It simply blocks dcv from coming into the amp or going from the amp to whatever is plugged into the input jack.

[pompeiisneaks]

Doesn't it also perform a bit of a high pass filter? I think it's going to be a non issue for guitar but if you plugged a bass in it would be a bit trebly.

I used an RC high pass filter calculator and it gave like 0.72 Hz or near 0 Hz. http://www.learningaboutelectronics.com ... ulator.php

Or is this not the right kind of setup with the Cap going to the 1M grid leak before the tube?

~Phil

[mhuss]

22nF and 1M has a -3db point of < 1hz, so it's pretty much just for DC.

[pompeiisneaks]

22nF and 1M has a -3db point of < 1hz, so it's pretty much just for DC.

Oh yeah I just had to google the bass guitar frequency range and found I'm up in the night, it goes from maybe 40Hz up, i.e. no impact

Nothing to see here, move along :O

~Phil

[bepone]

constructor for this amp for sure has some construction also with transistor amps. here it is not necessary, cap looks too high value