Help needed: 16 LED sound reactive setup not bright enough!

Hey,

Just finished a project with 16 LEDs (8 green, 8 blue) wired in parallel groups of 4 x 4 in series, attached to a TiP31c transistor and to the PC's 12v line from a Molex. The audio signal comes from the onboard HD audio header on the motherboard (Asus P5QL Pro).

The setup works ideally then in Always-on mode (wired a 3-position switch with always on, off and sound-reactive mode). The lights are ultra bright and the illumination is awesome.

The problem: when in sound activated mode, the LEDs only emit a faint flicker, if anything. The 4 LEDs closest to the power source are just a hint brighter than the others, but about 20% of the maximum brightness in always-on mode.
Also I noticed that if I crank up the volume in VLC player to 200%, the lights actually get dimmer and start to just flicker sporadically.

The LEDs are 3v, 20mA (http://www.dhgate.com/led-5mm-1-5v-...ultra/p-ff80808139bf02420139f43643ba34ef.html)

So any suggestions on what to try to turn this thing into a real light show? (preferably without any major changes as it is already secured into the PC case...)

Thanks!

 

Hey, thanks for the reply

Here's a sketch I made prior to building the setup. I know it's not the best but it was just for guidance so I wouldn't get lost while building it

I'd not like to get an amp as this was meant to be a cheap weekend project. Also, there is no resistance to the LED-s, they run on 3v, so no resistor needed...