Audio Degradation with 3.5mm to Toslink? [Archive]

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Fr3@k3r

10-07-07, 05:28 AM

Mpegger

10-07-07, 07:20 AM

Yes, there will be audio degradation because the 3.5mm headphone jack is a regular analog stereo jack. You most definetly wont get 5.1 from a standard analog stereo jack, and the only stand alone units I remember that would take a stereo analog signal and convert it to a digital stereo signal, were more expensive then just getting a cheap-o PCI sound card that has a digital (coaxial or optical [Toslink]) output.

Oh and dont forget, unless the sound card supports Dolby Digital Live or DTS Connect, it wont output multi-channel audio either, just regular stereo, from the digital output. Only exception to that rule is when your playing back a DVD and merely pass the audio stream straight to your reciever to decode.

Theres a few options for sounds cards with digital outputs on NewEgg for $24 (not including shipping). But again, the output will just be a regular stereo signal only. If your receiver has multi-channel inputs, you could use one of those sound card with 3.5mm stereo jacks to RCA plugs adapter to connect your computer to your reciever.

Fr3@k3r

10-07-07, 07:41 AM

http://www.newegg.com/Product/Product.aspx?Item=N82E16829156001

and or

http://www.newegg.com/Product/Product.aspx?Item=N82E16829271001

whats your recommendation?

Mpegger

10-07-07, 07:53 AM

Thats a tough choice. I dont think you can go wrong with either card. I think the nod is usually given to the Auzentech cards because of thier upgradability. Change out the opamps, and the sound will improve. But if you plan on sticking with just a digital signal, then this wont matter as the opamps would only affect the analog outputs.

Fr3@k3r

10-07-07, 09:46 PM

yeah well ill have to make sure i have an open PCI slot on my server.. right now i dont think i do.. lol..

anyways thanks for the help

Sir Barton

10-07-07, 10:01 PM

You can go here (http://www.national.com/pf/LM/LM4562.html) to the National Semiconductor website and order free samples of the LM4562 opamps in an MDIP package. I ordered 3 for my Audiotrak card. Those LM4562s are all the rage on head-fi. The only catch with the opamps is that you still pay for shipping :(. By swapping the opamps, you can change the sound signature.

Mr. Roboto

10-07-07, 10:04 PM

im having trouble understanding why you need to tuse a 3.5mm jack at all...doesn't your onboard have a coax out at least?

Like I said in your other thread, both of those cards are overkill for just passing through 5.1 signals. Get an audigy 1 or something in the classies for cheap if your board doesn't have on on board coax.

Fr3@k3r

10-07-07, 10:54 PM

im having trouble understanding why you need to tuse a 3.5mm jack at all...doesn't your onboard have a coax out at least?

My motherboard isnt a high end, in fact its a low end board as shown in my sig for the HTPC

Like I said in your other thread, both of those cards are overkill for just passing through 5.1 signals. Get an audigy 1 or something in the classies for cheap if your board doesn't have on on board coax.

Well unless you have another Idea for getting Dolby Dital 5.1 or DTS i dont see how I can do it. My motherboard has simple Realtec Audio insert with Out, In and Mic lines and thats it.

http://www.msicomputer.com/product/p_spec.asp?model=K9N4_Ultra-F&class=mb

theres my motherboard.

Mr. Roboto

10-07-07, 10:59 PM

Well unless you have another Idea for getting Dolby Dital 5.1 or DTS i dont see how I can do it. My motherboard has simple Realtec Audio insert with Out, In and Mic lines and thats it.

Like I said, get a cheap card, like an audigy 1, and just use it to pass through DD/DTS. Thats what I have in my HTPC and it sounds great!

Fr3@k3r

10-07-07, 11:03 PM

Like I said, get a cheap card, like an audigy 1, and just use it to pass through DD/DTS. Thats what I have in my HTPC and it sounds great!

how exactly does that work?

edit..

what about this sound card?

http://www.newegg.com/Product/Product.aspx?Item=N82E16829120103

and here's the review

http://techgage.com/article/chaintech_av-710_71_sound_card/

Mr. Roboto

10-07-07, 11:24 PM

how exactly does that work?

edit..

what about this sound card?

http://www.newegg.com/Product/Product.aspx?Item=N82E16829120103

and here's the review

http://techgage.com/article/chaintech_av-710_71_sound_card/

That's actually a popular choice for an inexpensive sound card. When you're using the coax or toslink out on a sound card to play a 5.1 source, they card just passes through the signal to the receiver. Because of this, it doesn't do any sounds processing, so there's no real difference between a 20 dollar, and 80 dollar card.

Fr3@k3r

10-07-07, 11:33 PM

rightio, so this should be me choice.. not to see if i have any PCI slots open LOL

Mpegger

10-08-07, 06:14 AM

That's actually a popular choice for an inexpensive sound card. When you're using the coax or toslink out on a sound card to play a 5.1 source, they card just passes through the signal to the receiver. Because of this, it doesn't do any sounds processing, so there's no real difference between a 20 dollar, and 80 dollar card.

Except that the pass through will only work on a pre-encoded DD or DTS track, and not on any multi-channel sound the computer may output.

For example, playback of music through WinAmp, WMP, or any other music playback software will be in stereo only. Even if you have some type of plug-in to output to multiple speakers, the digital output will only pass through a standard stereo PCM signal. It would be up to your reciever and whatever sound modes it supports to have multi-channel sound.

Same would go for any regular TV signals you record from the TV or cable box (not including those HD channels that have multi-channel sound). It would still be a normal stereo signal outputing from your computer to the reciever.

Lets not forget that if the sound card only supports 2 channels to begin with, it will never output anything more then that.

But you do make a good point about not needing anything more then that, so long as the reciever handles all the multi-channel aspect with its built in sound modes, such as Dolby Pro-Logic IIx, DTS Neo:6, or some other built in formats (Hall, Concert, etc).

Fr3@k3r

10-08-07, 06:17 AM

just so you guys know and im getting full info

http://www.sonystyle.com/webapp/wcs/stores/servlet/ProductDisplay?catalogId=10551&storeId=10151&langId=-1&productId=8198552921665061593

thats the receiver..

So with that Chaintech i will get 5.1 sound right?

Mpegger

10-08-07, 06:25 AM

Again, depends on your needs. Only viewing TV/DVDs with your HTPC? Go with the cheap sound card with a digital output and let the reciever handle the decoding and multi-channel sound processing.

Are you gonna do any gaming that would require or be best with multi-channel sound? You'd need a DDLive or DTSConnect card.

But seeing as how you have a dedicated machine for that, I would guess your strictly viewing TV/DVDs on your HTPC.

Fr3@k3r

10-08-07, 06:35 AM

its mainly for Video, Music and Recorded TV Shows.. I dont do pc gaming very much anymore and like you noticed its on a difference machine all together

Jon

10-09-07, 09:05 AM

I have the Chaintech card and it will be fine for your intended purposes. I used it for a while on an interim HTPC board that did not have optical SPDIF onboard. That Chaintech is also about the cheapest solution available that does not alter frequencies of supported audio formats. Many older soundboard codecs (i.e. pre-HD Realteks) will convert, for example, a 44KHz DTS track to 48KHz before sending it to the external receiver. The same goes for a 44KHz PCM WAV file on a CD.

Mpegger

10-09-07, 09:27 AM

Jon

10-09-07, 10:10 AM

Ummm... unless the card is decoding the DTS track, converting the sample rate, and then re-encoding the tracks back into a DTS format, its not doing any converting of any DTS or DD(AC3) tracks.

Your probably thinking about PCM audio. Its just a regular uncompressed ditigal audio stream, much like a wav file, that is used when streaming audio from one component to another.

Older Realtek (850 and below) and even a lot of the Creative cards (e.g. Audigy2, other than the NX) output only 48KHz. The audio isn't being converted or decoded, it's being resampled.

In other words, it's not true pass-through. The drivers used are forcing a resampling of the bit stream before putting it to the receiver. Plenty of testing done on it at Hydrogen Audio and AVS forums.

It appears the hardware may be capable of sending unmodified sample rates, but the drivers that are produced don't allow it.

Mpegger

10-09-07, 10:43 AM

I know about the resampling issue with playback streams. But again, unless the hardware is internally decoding the DTS/AC3 stream (which is a type of compressed audio much like a zip file, ogg, mp3, wma, etc etc etc), upconverting the sample rate, then recompressing the end result back into the same format it was prior and sending it on its way to the external decoder (reciever), then there is no resampling being done of a DTS/AC3 stream being passed through the hardware to the receiver. If that were the case, forms of DDLive and DTSConnect would have been possible through software hacks to enable the hardware to encode multi-channel wavs or DirectX streams a looooong time ago, not to mention software hacks to enable the hardware to decode a DTS/AC3 stream internally so there would be no need for software decoding.

Again, what your talking about is normal, uncompressed audio streams being played back through the sound hardware. An mp3 file being played through WinAmp is just have the audio stream reconstructed by the software decoder, then sent to the sound card. A wma file being played back through WMP, is having the same process occur. The mp3 and wma file is merely a mathematical representation of the original audio samples. The sound card wouldnt know what to do with it unless there was something (a decoder) to interpret the file and feed the sound card a standard audio stream in a standard format. DTS/AC3 work the same way.

Jon

10-09-07, 12:02 PM

What I'm saying is that if you put in an audio disc containing 44.1KHz DTS tracks and set it for digital passthrough on a card that I'm describing, the receiver will receive that as a 48KHz DTS stream. You're going to have to explain, in detail, how that is to be considered normal.

Fr3@k3r

10-09-07, 01:08 PM

jesus i didnt expect this to become an all out war on freaking audio..

i just wanted 5.1 sound from my HTPC to my Receiver..

Jon

10-09-07, 01:56 PM

jesus i didnt expect this to become an all out war on freaking audio..

i just wanted 5.1 sound from my HTPC to my Receiver..

Get the Chaintech.

Mpegger

10-10-07, 04:59 AM

jesus i didnt expect this to become an all out war on freaking audio..

i just wanted 5.1 sound from my HTPC to my Receiver..

Get the Chaintech.

No war. Just peace! :beer:

Get the Chaintech.

I just like to make sure you fully understand what your getting. Remember, it will allow DTS/AC3 (Dolby Digital) pass through from any DVD movies your playing to your reciever. It will be up to your reciever to decode the audio and provide the 5.1 sound.

Any computer audio, which will include any TV you are watching (unless its a HDTV channel that provides a 5.1 audio stream) will only output a stereo PCM signal to your reciever. It will again be up to your reciever to provide a 5.1 audio field from the 2 channel stereo.

And as far as the DTS Audio CDs, I didnt even know they still existed. DVD Audio seemed (to me at least) vanish almost as soon as it was introduced, and afaik, the Audigy line (2 and 4 I think), were the only ones capable to playing back the audio natively. I read up abit on DTS Audio CDs and it seems to have its own formats that are encapsulated within a DTS container. Much like a video and audio stream can be contained in a avi stream, the DTS stream could be acting as nothing more then a audio container. It could actually have uncompressed audio streams within the DTS container, as well as compressed audio streams. If the person playing back the audio stream didnt realize what type of audio information was contained within the stream (I highly doubt they missed that), it could have resulted in the resampled audio, of what they thought sould not have been capable of being resampled, even though it in fact was. I'm up in the air with that one as I never dealt with DTS (or DVD) Audio CDs. The DTS/AC3 streams I've been talking about in this thread, have been those on a standard DVD movie. No sound card sould be capable of altering those streams when in pass-through mode, as that would mean the card is capable of decoding and re-encoding those formats in real-time.

Joeteck

10-12-07, 01:07 PM

well im having a dilemma..

I have to use the on-board sound for my HTPC because i have no space or money right now for a new sound card.

I also am using the HDMI from my 2600XT and it will be going to my new Receiver..

the receiver is HDMI pass through and accepts the audio through a Toslink cable..

my onboard sound is a 3.5mm jack..

SOOOOO

Will i get any audio degradation with a 3.5mm to Toslink cable? and with i still get my 5.1 sound?

I was in the same boat as you, but I wanted 5.1 audio for playing games. So I did loads of research and got this (http://www.newegg.com/Product/Product.aspx?Item=N82E16829271002) one. I wanted to get the 8788 c-media chipset as it offered more of what I needed for DDL & DDC, plus is 192Khz, a big plus if you're reciever can handle it. I'm going Toslink to my Pioneer receiver and I can't believe how awesome it sounds. I also have a 10" 240 Watt sub... What more interesting is the Creative only outputs Digital in 2 channel....

And if you did go from your 3.5mm to the receiver it would be Dolby pro logic... (analog)