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previous: Sheldon Dingwall "or is of a jFet/mosfet input desig... -- 3/12/2004 1:36 PM

Re: Fernandez Sustainer -buildable?

3/13/2004 6:30 AM
eth	Re: Fernandez Sustainer -buildable? Sheldon, O.K.! I think your problem will be solved by putting resistors to ground on the input and output of this pre-amp. The pop is the sound of a capacitor, on either the input side or the output side of the pre-amp. Stick an ohm meter on the input of this circuit and on the output, I'm betting one of these spots does not show a reading. (maybe some jumping around of numbers- a capacitor is charging on the meters test current) I'm assuming alot hear, but ... input/output capacitors are used to isolate the d.c. voltage of the pre-amps bias voltage and idle voltage. A signal passes through a capacitor because it is a.c. The pop comes from that short period of time when the switch is transfering. If the external world end of the capacitor is not grounded through even a very high value resistor, it will charge up to whatever the bias or idle voltage is. ... Then upon full contact connection, that charge is discharged into your 100 watt marshall, turned up all the way to ten. ouch. So anyway, hopefully I can be useful... I'm crap at explaining. I'll get better though. And I'd be psyched if this helps, which it will, so get out your soldering iron!!!! later, Eth

3/13/2004 6:30 AM

eth

Re: Fernandez Sustainer -buildable?

Sheldon,

O.K.! I think your problem will be solved by putting resistors to ground on the input and output of this pre-amp. The pop is the sound of a capacitor, on either the input side or the output side of the pre-amp.

Stick an ohm meter on the input of this circuit and on the output, I'm betting one of these spots does not show a reading. (maybe some jumping around of numbers- a capacitor is charging on the meters test current)

I'm assuming alot hear, but ...

input/output capacitors are used to isolate the d.c. voltage of the pre-amps bias voltage and idle voltage. A signal passes through a capacitor because it is a.c. The pop comes from that short period of time when the switch is transfering. If the external world end of the capacitor is not grounded through even a very high value resistor, it will charge up to whatever the bias or idle voltage is. ... Then upon full contact connection, that charge is discharged into your 100 watt marshall, turned up all the way to ten.

ouch.

So anyway, hopefully I can be useful... I'm crap at explaining. I'll get better though. And I'd be psyched if this helps, which it will, so get out your soldering iron!!!!

later, Eth

Replies:

Dave Stephens Why on earth wold anyone want to ma... -- 3/13/2004 12:01 PM