This circuit has a gain of 6 dB for low frequencies from 85 Hz and can be used in a mini subwoofer. The circuit is from a Radio Electronics from March 1990.
The circuit shown in the figure is suggested by National Semiconductor and makes use of an...
This circuit, suitable for tube equipment, was found in an old documentation. It uses a high...
This circuit is part of an integrated circuit tester published in an article in Radio Electronics...