One solid way to improve in-car audio quality is to install an amplifier, but many people don't want their cars heavily modified. Blaupunkt's THA 555 is a plug-and-play amplifier that can be installed by anyone who's handy with tools and doesn't mind getting a little dirty. The THA 555 is a digital amplifier putting out 55 watts through each of its four channels, with an extra subwoofer channel pumping 200 watts. But the beauty of this amp is that, with one of Blaupunkt's model-specific wiring harnesses, you can fit it into a car with very little effort.
We had Blaupunkt show us the installation procedure in our Car Tech Testing Lab. The installer pulled the stereo out of the dashboard, unplugged the wiring harness, and replugged it and the stereo into Blaupunkt's cable. A third end of that cable lead out to the THA 555. After slipping the stereo back into place, we turned it on and were treated to an immediate improvement in our car audio, even though it was playing through our Testing Lab's six basic speakers. The THA 555 features controls on its back plate for fine-tuning the audio quality. It has a lower power draw than most amps, so much so that Tesla chose an amp from this line for its all-electric Tesla Roadster, because it would have less impact on the car's range. The unit itself is fairly light and small, at 1.6 inches thick and 14 inches long. This size makes it possible to install the unit under a seat or behind the glove box.