Subwoofer

Subwoofers are very powerful cock vibrators... at low frequencies, they can massage your dick!

I have a 300 watt 8" car subwoofer that I often masturbate with. The subwoofer is powered by a car subwoofer amplifier under my bed, powered by a 12v power supply. The amp comes with a "bass knob" or volume control, which allows me to control the intensity of vibrations.

Usually, I lie down and let my subwoofer rest on my crotch (the subwoofer is out of the box so it's a lot quieter and discreet). Then I play some bass-heavy tracks and let it play until I finish.

Ideally, my subwoofer plays below 25hz, which allows it to move a lot. It also keeps things more quiet since low bass doesn't travel far (I have roomates). Also my amp cuts out all high frequencies. I've been doing this for 5 years with no issues and never been caught.