Anyone Knows Where Can I Buy an Adjustable Capacitor?

[spaceman5]

I see..

Hopefully one day someone will have a nice idea how to make variable capacitors in similar size to fixed capacitors.
By using a new structure or newer materials..

 

[MarcelvdG]

What application have you got in mind and of what order of magnitude should the capacitance be?

 

[spaceman5]

The things I want to start with is Equalizer.

After that, any kind of sound improvement