Hi all,I'm a noobie here and don't seem to get much from other Forums so I thought I'd give this one a go.I'm trying to put together a circuit for a Subwoofer controller that consists of the following.
Ist an op-amp buffer stage,then a 24db Linkwitz Reily lowpass filter set at 40 hz,then a gain stage.The signal then goes thru a 12db Linkwitz Reily High pass filter at 7 hz to a Linkwitz Transform and bridge stage to drive a pair of mono amps.
The Linkwitz Reily website gives details of a similar controller for use with his Thor subwoofer (
https://www.linkwitzlab.com/thor-orion.htm) but he doesn't use a highpass filter to remove subsonics,where should this stage be best put?And also, two resistors normaly added to an op-amp makes a gain stage,I'd like to make this variable,so could the two resistors be replaced by a Pot?
I did build a basic circuit with just the buffer,24 db lowpass and Linkwitz Transform.It worked in my car and indoors and sounded amazing but I felt it needed more gain to drive the amplifier properly.I went back to Linkwitz's site and discovered I hadn't added the gain stage.Without knowing how much gain to add and not being good at Math,I found the basic building block of a gain stage and decided to use a pot instead of resistors, now I'm thinking that when I've found the correct level I can substitute the pot(after measuring with me meter) with the correct resistors.
What do you think of my description? Is the Highpass filter and Gain stage in the right order?
Many Thanks Y'all. Mikee55