When speakers distort sound it's unpleasant:
- High notes sound harsh.
- Low notes sound boomy.
- Voices sound indistinct or unnatural.
Most people begin to hear some distortion at quite low levels and the bigger the room the louder the volume required to fill it. Unfortunately, as the volume is increased the more likely it is that a speaker starts introducing distortion.
The best models in this test for loud undistorted sound at a distance of two metres are the Yamaha YSP-4000, Yamaha YAS-71 and TEAC, and the worst is the Samsung. The Samsung starts to distort when the sound isn't much louder than a loud conversation (69dB), but the better ones can be very loud (89dB) before distortion begins.
The listening panel was impressed with the Yamaha YSP-4000 because it can project sound so it appears to come from an area much wider than its physical size. They also like its clarity and even response across frequencies. Unfortunately, it is let down by its subwoofer, which lacks power. The Sony also impressed most listeners, but one panellist found the bass a little too intrusive. It scored well in technical tests and would also be a practical solution if you're looking for a piece of furniture on which to put your TV.
The panel was not impressed with the Samsung, Yamaha YAS-71B and TEAC because they don't provide a surround sound experience. The Samsung bass is boomy even when turned down, and the TEAC has a noticeable hum when it's on. The panellists described them as almost mono or lacking in a sense of space.
The Denon models sit somewhere in the middle. Their sound is clear and they provide some separation in stereo mode, but they're not nearly as good as a 5.1 surround sound system - see Setting up a sound bar.
Loud isn't everything
If the sound bar is not providing a balanced and accurate representation of the recording in the first place, distortion will only detract from an already poor listening experience.
Although the technical testing includes lots of measurements, such as channel separation and frequency response, it cannot measure a subjective response. Our panel was looking to be surrounded by sound, warmth and clarity; if they were left flat, they marked accordingly. See how we test.