Now what we need is a software that allows to load VST plugins, There is Nuendo Surround Edition which is great.
Now the possibilites are HUGE, you can use any professional plugin you want, this will include Voxengo Pristine Space to do convolution ! We are going to redirect WDM sounds from software like Foobar, Zoom Player, BsPlayer to an Asio application that allows to load any VST plugin. Now to do better and overall with any software (so this will include DVDs), you need a card that can do internal routing, such as ESi or Audiotraks with the great Directwire tool !ĭirectwire allows to redirect digital audio sound from one application to another. Īnother great software is ACXO, working in Asio mode : You can choose the cutoff frequencie, type of filtering, gain. You can use a foobar plugin that allows to do filtering. You can use FIR filters, professional quality tools and plugins.įiltering on stero sounds with any decent card : You can use a specifi amp for each way, in particular a very powerfull amp for the low frequencies.Įverything is done before any Digital-Analog conversion. The speakers are not "slowed down" by the components of the filter. There is no loss between amps and speakers, no interaction between the speakers. Settings are quite easy and overall instantaneous (which is not that easy if you use passive filters). It is better using a video refresh rate that is a multiple of the chosen speed. If Aduio speed was not changed, put reclock on 24 fps. If Audio speed was already changed, put reclock on 25 fps. You can easily notice if the DVD has a corrected sound or not : natural of the voices and soundtracks allow to judge. When put to DVD using 25 frames par seconds, if the change of speed is not taken in consideration, there is a kind of shift to the high frequencies, a little bit as the doppler effect. It also allows to correct the "Pal Speed-up" problem : movies for the Cinema are recorded using 24 frames per secondes. It allows to synchronize video and sound based on the video card clock. ZoomPlayer allows to use Reclock as an audio render. You your own matrix coefficients, if you use 5.1 just put 1 on the diagonal, if you use 4.1, 1 on the diagonal exept for the 2nd column (0.7071, 0, 0.7071, 0, 0) : this will send the central speaker to the front speakers. Remove Auto Gain and Auto Matrix as they bring dynamics compression. ZoomPlayer, filter properties, AC3Filter : I chose AC3 filter for the moment because it offers a lot of options. the most important thing is to remove dynamics compression and to avoid clipping (AC3 filter for example plays too loud). Zoom Player Pro, DVD mode, Player Options :Īs we are decoding sound with the computer, the choice of the codec and its settings are very important.
What you need is Zoom Player Pro : you can choose the video codec you want, the audio codec you want, audio and video render.Īmong all the codecs available : Cyberlink PowerDVD, Intervideo WinDVD and AC3Filter.
If the sound volume tou want is too low (-X db), its digital code will encroach the code of the sound and there will be quality loss. As the sound card DACs are working at least in 24 bits, you can reduce sound volume a lot before having digital loss. Using a power amp directly on the sound card, volume is set in the sound car panel. Just use Foobar with the Kernel Streaming output (or Asio, plugin needed). If you don't want to process sound you can choose any pro sound card you want otherwise stick to Esi. The choice of the card depends on what you want to do and in particular filtering/Room treatment or not. We are not talking of consumer sound cards here even the best Creative sound cards. Of course, as the sound card is doing more job, it needs to be a good quality sound card.
My PC replaces CD player, DVD player, preamp and filters, this is more complicated but much more interesting. To play DVD's just choose the digital output in the player settings.Īctually this is not that kind of use I am interested in. When you got a decent sound card, you just need to use Foobar with Kernel Streaming (Foobar2000 > Preferences > Output > Kernel Streaming), chose your soundcard in "Go to Settings". An AV amp receiving resampled DTS will play a kind of rose noise. You can also read DTS CD-Audio that use 44.1Khz. Having a 44.1 Khz compatible sound card allows not to spoil CD-Audio LPCM, it just pass it through the card without resampling. Most of the cheap cards only support 48 Khz and so they resample every 44.1 Khz signal to 48 Khz. You just need a good sound card that supports 44.1 Khz without resampling. The most common manner is to use the computer as a digital source and to use an external DAC (most of the time an AV Amp). There are two manners to use the computer as a source :