22 April, 2010

Digital video/audio formats?

I recently acquired myself a hybrid Hi-Fi HD surround receiver to try and organize all my A/V-cables, and also to enhance my listening experience both with music and film.

Honestly, I didn't actually expect to notice any difference between Dolby Digital/DTS surround sound, and the new formats Dolby TrueHD and DTS HD.

But I certainly did.

Dolby Digital (or "DD") was the first fully digitized stream-standard for movie-surround. This means that the audio-track on the DVD/DVR/BD medium is digitally recorded and encoded (analogue soundwaves, converted into computer-data, further reducing distortion and noise).

  • DD uses the AC3 (Audio Codec 3) codec to compress 5.1 surround channels of sound at varying sample-rates of up to 48KHz.
  • DD formats are usually noted as "DD 2.0" or "DD 5.1" on specs (covers,etc.).

Dolby TrueHD (or "DTHD") is the first Dolby-implementation of a high-definition sound codec. Dolby based the DTHD codec on Meridian Lossless Packaging technology, making it a lossless format (meaning, it doesn't compress the audio-data, but stores it fullrange). Because of this, DTHD can handle up to 24Bit 96KHz audio, at an 18MBit/s transfer-rate, over 14 channels. A true High-Definition multi-channel system.

In conclusion, I think HD formats are for enthusiasts. If you aren't an audiophile (like me), chances are you won't even notice any differences. Unless you have a reasonably up-2-date Hi-Fi system with HDMI inputs or at least digital coax/optical inputs.

To put it in other words:

If Dolby Digital "is like going to the cinema"
Dolby TrueHD "IS the cinema"