Howto: ABX Test for surround sound (Prologic) with mp3
Reply #3 – 2004-02-03 12:56:06
Questions: 1. Which software do we need? If you have a working hardware setup like this ... Source audio from CD / DVD movie audio prologic encoded -> PC playback -> soundcard digital/line out -> Amp digital/line in -> processing to 5.1 surround -> playback through 5.1 speaker system ... you can simply use ABX software like foobar2000's abx tool or ABC/HR You need to encode the test samples, e.g. using recommended lame settings/compile (-> sticky thread in mp3 section). Foobar2000 handles decoding/replaygain etc. for ABXing (semi-)automatically; if you want to use ABC/HR or WinABX you need to decode to .wav manually before you can start testing. If there's a software that can do the same as hardware prologic decoders, even better. I this case we could create test samples that can be used by everyone with a 5.1 speaker setup. Does anyone know/have such a software?2. What about the hardware? see above3. Where do we get "clean" samples from? If I understand correctly, prologic II works with every stereo source, but it would be nice to have some prologic encoded source. So - if anyone has a dvd with such an audio stream - provide a sample, please.4. How's the test to be done? With a hardware setup comparable to the one described above, just use the ABX software as usual (details see FAQ)...use S/PDIF or 6channel analog? For soundcard -> amp s/pdif if digital inputs/outputs are available. If I understand correctly, signal sent from soundcard to amp is 2 channel, it becomes 6 channel after prologic decoding by the amp, no?..enable or disable (for DPLII maybe) soundcard settings (very difficult to setup - spent some houre infront of it and it still doesn't work as I want it to)? What soundcard settings are you talking about? - Generally, in my understanding, the signal should reach the amp as pure as possible...use headphones or speakers? Prologic is designed for use with 5.1 speakers system, so using headphones for testing will be quite pointless IMO.