D
Demolitionman
New member
Hi All,
I've been a fervent reader of this forum for many years & thanks to many of you,I have picked up a vast amount of very interesting & invaluable information & tips from you guys.So here I am..with a problem I'm having with my new project.
I've an AKG C411L mic without the power pack/preamp,so decided to build one of my own...easier said than done! Here is why....
The buffer circuit given below is part of a mic preamp which works very well with the Panasonic WM61A electret mics. However,when I connect the AKG 411 it generates some sort of "Pumping or motoboating effect,yet it is working apart from from this problem.
I've rewired/modified the mic as follows;
Pin.1-shield
Pin.2-Signal input to buffer
Pin.3-bias/suply to mic
As you can see from diagram 2,the original wiring;
Pin.1-Shield
Pin2+3 tied....to signal out
The preamp is running on a well designed psu @ +/-12v dc
Is ther something I've overlooked at component level or is that I've the mic wires wrong? Can someone give me some clue or advice at least as to what I might be doing wrong?
Thanks
I've been a fervent reader of this forum for many years & thanks to many of you,I have picked up a vast amount of very interesting & invaluable information & tips from you guys.So here I am..with a problem I'm having with my new project.
I've an AKG C411L mic without the power pack/preamp,so decided to build one of my own...easier said than done! Here is why....
The buffer circuit given below is part of a mic preamp which works very well with the Panasonic WM61A electret mics. However,when I connect the AKG 411 it generates some sort of "Pumping or motoboating effect,yet it is working apart from from this problem.
I've rewired/modified the mic as follows;
Pin.1-shield
Pin.2-Signal input to buffer
Pin.3-bias/suply to mic
As you can see from diagram 2,the original wiring;
Pin.1-Shield
Pin2+3 tied....to signal out
The preamp is running on a well designed psu @ +/-12v dc
Is ther something I've overlooked at component level or is that I've the mic wires wrong? Can someone give me some clue or advice at least as to what I might be doing wrong?
Thanks
