# External / Internal DAC cd player streamer Htpc bitstream?



## nickb (Mar 21, 2013)

Folks, I have had something on my mind that has bothered me for the last 12 months now and despite endless searching have no answer as yet.

I have a pretty decent system. Kef 205/2 fronts Kef 204/2 centre, rotel 1572 processor, b&w rears, emotivia expr 5 amp etc. 

Everything sounds good right, but I feel there's a even more SQ to be had.

Going back to the source I have a pc (amongst other components) connected to AVR via hdmi on back of ati rad-eon graphics card. This card is able to process and bitstream 5.1 audio. I bit-stream audio to AVR so that dac's in AVR process the sound. I figure that the AVR's dacs are a better sound than the graphics cards sound processor primarily due to price i.e the processor costing 10 times as much.

Anyway, I figure the weak link in my system to be the Source, in this case the grapics cards sound processor. I therefore looked to upgrade to a really good sound card. However, After searching the net, I have found that the bitstreaming source has no impact on quality. i.e. I could bitstream from $10 card and $1000 card to processor and as the processor's dacs are processing the sound, no difference in sound quality can be expected. Surely this can not be right?

I am very confused about the whole thing. If this where true, this would mean you are better off spending $1k's on processor and $1 on source equipment provided it is able to bitstream. ? 

Lets say you brought a Blu ray player for $10 that could bitstream, then you brought a $1000 player that could also bitstream. By the theory above both would sound identical when bitstreaming to AVR is this correct?

Again, you can get the rotel cd player or streamer for arguments sake at a fairly big price. All units Processor/cd player/streamer use the same dacs so they would sound the same right? But if you where able to bitstream both streamer and cd player to AVR and use the AVR's dacs the cd player/streamer would be a complete waste of money if you get me. On the other side of it, if you where using the cd player/ streamers dacs the processor would merely be a volume knob as such and all dac's redundant.

Guys, I don't know if I am brain dead here but would appreciate the expertise of someone who understands this.

Many thanks


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## AudiocRaver (Jun 6, 2012)

This is an area where the theoretical and the real world can be quite different.

Your assessments as stated sound correct, if you are bitstreaming and all other factors are equal, put the money where the DACs are. Real world - the AVR as a volume control involves digital signal processing that should be high quality, but volume is a pretty simple DSP function and if you are already paying for good DACs, that processing will surely be handled well, too. Discussions of DSP quality among well-known brands seems to be pretty rare, so probably not an issue.

Bit streaming at the source end involves chipset, pll jitter, audio drivers and buffers and the way the operating system, other drivers, interrupts and the like all work together. A motherboard that says it can bitstream may or may not be able to do so with pristine perfection when all these factors are combined.


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## nickb (Mar 21, 2013)

Thanks for your input.

So in short, bitstream source does vary in quality.

Having spoke to a reputable hi fi dealer he has also confirmed this to be the case.

So if one where after audio perfection from a PC source (bitstream music) it would seem that there is no real solution High Fidelity wise to this problem?

Thanks


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## AudiocRaver (Jun 6, 2012)

There are media players that claim to do better at this. On the hardware side, not sure what options are available.


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## AudiocRaver (Jun 6, 2012)

A quick followup:

There are several "high-end" audio players that claim to deliver super audio performance:
Audirvana
Channel D (Mac only)
JPlay

Claims of superiority are pretty hard to prove.

jRiver, XBMC, foobar2000... the list goes on... almost all have capability to play from uncompressed files in memory, which bypasses pretty much all but the interface to get out of the computer.

For anything using USB, an interface with "Asynchronous USB" design and driver is touted to be the ideal link for perfecting audio transfer out of a computer.


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## RTS100x5 (Sep 12, 2009)

Ive been using my 5.1 analog sound card now for some time as it definately has a superior SQ vs HDMI > AVR decoding process... My sound card is no longer available except on Ebay , however this HT CLARO has the same option to upgrade the OPAMPS. I used the BURSON AUDIO discreets and they made a believer out of me...
Now with JRIVER audio configured using ASIO output format so Im getting 5.1 @ 96k / 24 bit analog.... Im also running a VST plugin (IZOTOPE-OZONE 5)..... The sound Q is fantastic vs AVR processing so Im encouraging you to look in that direction for SQ utopia....See you there :wave:

Here is the HT CLARO w 7.1 analog 

http://www.newegg.com/Product/Product.aspx?Item=N82E16829271005

Here is the BURSON OPAMP page (great reading as well) 

http://bursonaudio.com/DIY_HD_Opamp.htm


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