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Posted By: sauniq finding Computer bitrate/sampling rates. - 08/07/10 06:43 PM
HI.

The sound output from the headphone jack to my preamp using a jact to rca connection sounds really good, almost compareable to my cd player. I was thinking about upgrading my cd player but because my computer sounds so good, i need to know what the conversion etc is on the pc just to satisfy my curiosity.

I am looking for some adivce on how to find out what the output of audio is on my HP Pavillion Laptop, the model is a DV6 1120.

I have exausted all attempts to find out about this machine.
Posted By: fredk Re: finding Computer bitrate/sampling rates. - 08/07/10 07:00 PM
What OS are you running? For XP everything goes through Kmixer and is down/up sampled to 16 bit 44,100 Hz.
Posted By: sauniq Re: finding Computer bitrate/sampling rates. - 08/08/10 04:24 PM
I us windows vista 64 bit. It has an IDT(intergrated device technology) program called audio manager where you control the settings; change the device output, altersound output etc.

Thanks for the reply.
Posted By: fredk Re: finding Computer bitrate/sampling rates. - 08/08/10 04:33 PM
In Vista you can bypass the internal sampler, but I don't know how easy/obvious this is. There are a couple of people here who probably know.

Honestly, I don't think you can hear the difference. In blind testing, even High bit rate MP3s were indistinguishable from full bit rate recordings.
Posted By: sauniq Re: finding Computer bitrate/sampling rates. - 08/08/10 05:41 PM
I have heard that opinion by lots of well respected people, and I appreciate the comment.

hope google helps me with findout out how to by pass the sampler.
Posted By: jmone Re: finding Computer bitrate/sampling rates. - 08/08/10 09:01 PM
Vista onwards has a Audio Renderer called WASAPI Exclusive that bypasses all the mixers (keeps the resultion, bit depth, and channel configuration matched to the audio stream being played). DirectSound (the defualt) will remix everthing based on the setting you set in the Audio Control Panel.
Posted By: sauniq Re: finding Computer bitrate/sampling rates. - 08/09/10 01:21 AM
This WASAPIthat by passes the mixers, how or where do I find this?
Posted By: fredk Re: finding Computer bitrate/sampling rates. - 08/09/10 02:02 AM
That may be the default behavior in Vista. It would certainly make sense.
The WASAPI must be requested by the client application. If the player program doesn't support it, you won't get it. That said, the mixer in Vista/7 is excellent, and isn't something you should worry about degrading the sound quality. The WASAPI was provided after much whining by "enthusiasts". It was Microsoft's original intent to always round sound through the mixer.
Posted By: jmone Re: finding Computer bitrate/sampling rates. - 08/09/10 08:22 AM
WASAPI has a heap of benefits that may or may not be appropriate for you. As mentioned, you need your client application to support the selection of the Audio Renderer for the Audio / Video playback section you want. Other options include the default DirectSound Mixer and ASIO (which WASAPI is replacing).
I certainly prefer WASAPI over DirectSound and there really is no reason why you would not use it even if you don’t "hear" any difference. Apart from eliminating another resampler in the output chain, you get the benefit of the dynamic channel output configuration you get with WASAPI.
Say you set you PC to match your 5.1 speaker config and you play a 2ch Audio track:
1) DirectSound: will resample it and then output a 5.1 signal where 3.1 of the channels are blank. This will hamper any post processing by your receiver as it thinks it has 5.1 (not 2.0 channels)
2) WASAPI: will not resample the Audio but will also change the sound cards output to match the number of channels, now your Receiver is getting 2.0 channels
The same goes when you start outputting Video. The Audio section can be a mix of 2.0, 5.1 etc and it is important to get the output correct. You can not do this with natively with Direct Sound but it works out of the box with WASAPI.
I will give you that, the "present, yet silent" channels are an annoyance.
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