dred

Didn't try to scare him ... the 20 hz thing was just an example I have built quite allot of enclosures for car and home use but never feel the need to post them on the internet, i'm more of the lurking kind thats why my postcount is subzero BTW: sonotube lenght = speed of sound : frequency Hope that is of any help grtz.

Find your sub's res. freq. and tune the tube to it. "At 20 Hz, the wavelength is about 55 feet, and this is where a 14 foot tube will resonate."

Something like this? Specs TT2250D CLASS D Monoblock Power Amplifier Max Power (1 ohm) : 2250w x 1 RMS Power (2 ohms) : 1500w x 1 RMS Power (4 ohms) : 800w x 1 Signal-to-Noise Ratio : 100dB Frequency Response : 20Hz-20kHz Illuminated Logo Frequency Response 20 Hz to 250Hz 2 Amps can be strapped together for double the power Remote Level Control Built-In Continuously Variable Low Pass Crossover 24 dB/Octave Continuously Variable Bass Boost 0-18 dB Chrome Plated Connector Dimensions: : 19-9/16"L x2-1/4"H x 11-3/4"W otherwise a pic would be handy oh btw i prefer Lurker over n00b grtz.

http://ampguts.realmofexcursion.com/O2_Audio_OAD3000.1/ or http://www.lightav.com/car/planet/titanclassd.html grtz.