Do hdmi to hdmi+optical converters do a good job at cleanly transferring the digital audio to receiver?

Coyle

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May 15, 2020
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I have an htpc setup that I've just been running the 3.5mm audio jack from the pc to my surround sound systems av rca inputs; it doesn't have hdmi in, but it does have optical input; just wondering how well these work; are they comparable to using a motherboard with s/pdif onboard? Thanks.
 

Muadib

Lifer
May 30, 2000
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Optical works great! You can get Dolby digital sound over it, while the 3.5mm jack will only give you stereo. I'm pretty sure spidif will only give you stereo too.
 

Dranoche

Senior member
Jul 6, 2009
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You're going digital to digital so it should work fine, and the same as an optical line direct from the source. Assuming there aren't any hdmi handshake issues with the converter/splitter.
 

mikeford

Diamond Member
Jan 27, 2001
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I suspect the splitter may work better than onboard or via a sound card spdif optical or coax. My own experience is that driver support is VERY weak in terms of licensing any of the "good" sound formats, often really only doing stereo or just pass thru from the DVD player.
 

Coyle

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May 15, 2020
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I suspect the splitter may work better than onboard or via a sound card spdif optical or coax. My own experience is that driver support is VERY weak in terms of licensing any of the "good" sound formats, often really only doing stereo or just pass thru from the DVD player.

Perhaps there is something I'm not understanding; I was under the impression that running the digital audio straight from the motherboard to my receiver that would then process the signal, it has dolby pro logic, etc. It's not onboard optical or a sound card; is just a bracket that connects right to the motherboard's spdif header, is this:
91nedXFQfcL._AC_SL1500_.jpg
 

mikeford

Diamond Member
Jan 27, 2001
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Pass thru should work fine, whatever your DVD drive supports, more or less goes out the spdif that same as it does for analog outputs. What rarely happens is the motherboard maker paying the license fees for encoders to the various formats. So your 7 channel receiver, and 7 channel (DTS or whatever) onboard sound chip, only works in stereo. Same is true for most non crazy expensive sound cards, chip supports all sorts of modes and formats, driver does not with no possible upgrade.

Dolby Pro Logic might work, as it is a pure analog signal, ie tricks done to and decoded from a stereo analog signal passed between devices, vs digital formats.

No harm in trying it, maybe works fine for your needs, or even if it doesn't actually work, it still may be ok.
 

Coyle

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Sure, I mean it sounds good now with just a little dell 3010 connected to rca, streaming sounds pretty good. The dolby is digital: " Dolby Digital, Dolby Pro Logic II, DTS, and proprietary Sony surround options"
"This system incorporates with Dolby* Digital and Dolby Pro Logic (II) adaptive matrix surround decoder and the DTS** Digital Surround System." I know is old tech but I think either way it'll sound good. The motherboard has DTS Sound Unbound which is a surround feature...well, guess I should just go put it together and hook it up, then will know.
 

AnitaPeterson

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Apr 24, 2001
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I have that exact setup motherboard > bracket > receiver replicated across several HTPCs in my house. The SPDIF coaxial (RCA) will output multi-channel sound to the receiver, according to whatever media/codec you're using; it's only the optical output that's restricted to stereo.
 

Dranoche

Senior member
Jul 6, 2009
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TOSLINK optical and digital coaxial with RCA, at least on consumer-level hardware, both use the S/PDIF standard. S/PDIF only supports 2-channel uncompressed audio. For surround sound it has to use compressed formats. Any potential physical bandwidth differences between optical and coax don't matter as the standard being used is the restriction.
 

Coyle

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May 15, 2020
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I have that exact setup motherboard > bracket > receiver replicated across several HTPCs in my house. The SPDIF coaxial (RCA) will output multi-channel sound to the receiver, according to whatever media/codec you're using; it's only the optical output that's restricted to stereo.
So, would you suggest using the digital coaxial instead of the optical?
I've edited this post as my initial impressions were that the digital was sharp; either it got better overnight--I like to listen to audiobook lectures before going to sleep and the voice audio was really unpleasant so I went into the mobos software and turned off a bunch of the enhancement features and then the voice sounded normal. Next day either I had gotten used to the new sharper digital sound, turning off those enhancements worked or whatever it sounds much better now; even with the digital optical I find that I get better sound to the rear speakers using AFD Multi over Prologic etc.
 
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Dranoche

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Digital coaxial and optical TOSLINK will both be carrying same signal. Over a longer distance there is technically potential for the coaxial cable to pick up noise. You had previously asked about what RCA cables to use if going with coaxial. You can technically use a traditional RCA audio cable in place of a coaxial cable but it probably does not meet the spec for coaxial and may have some issues.
 

Coyle

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May 15, 2020
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I'm getting used to it now; wasn't accustomed to the sharpness of digital, but really it's more of a clarity issue; everything is sharper, the bass levels more distinguishable, just overall so much better, just took a while to get used to the difference; initially voices sounded harsher but now--and I see that the other night when I played around with the mobo's audio software I guess I got it right, thought I'd turned off all special effects but in fact I turned the sound profile from balanced to extreme, bass boost, and removed theater to none, etc; funny what one can do when half asleep, just wanted the lecturer's voice to sound right. Seeing that it's working so well now I don't want to mess with it; there are many steps involved in changing over from one type of audio to another--syncing up between windows and the mobo's software; I got a good optical cable and it's only 1.5' with 90' angles so straight across from htpc to receiver. In the beginning I was having some kind of problem getting the toslink to connect and hooked up the monster cable and heard audio; but then figured out the toslink just needed to be pressed further into the htpc bracket to connect; this is the toslink cable I got, with this 90' adapter for the other side. Here are the monster cables I have:monster cable.jpgmonster cable 2.jpg
 

Dranoche

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TOSLINK connectors aren't always great. Sometimes they just don't want to go in, and once they're in sometimes they still feel loose. That said, never had one pop out on its own. Always seem to have random RCA plugs that want to lose grip on the terminal. Too bad BNC connectors aren't a thing on consumer level hardware.
 

Coyle

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May 15, 2020
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I hooked up the coaxial rca cable, it worked ok, is 4' and pretty well shielded (CL3) and 75-Ohm on the video cable; so is this the same then as a digital coaxial cable?
 

funboy6942

Lifer
Nov 13, 2001
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Get something like this and dont look back ;) (click me)

61jK9Z4udxL._AC_SL1200_.jpg

Then pair it with this....(click me)

71x55GmOuvL._AC_SL1200_.jpg

And with them 2, and a older AV receiver with or without hdmi, for you can have it all just go right to your tv, and your golden for ANYTHING that you should ever need to hook up. I have everything going to the top pic switch, then to the bottom, the spdif going to my old sony. I then also have a spdif from my tv going to my old, non hdmi btw, Sony in the 2nd jack so my smart crap (amazon, Vudu, etc) can be decoded into 5.1 with it.

And if you want to hook headphones to all that, get a 15 foot or longer rca stereo cord, then a male rca to 3.5mm female, and plug you phones to it, and flip the switch.
 

Coyle

Member
May 15, 2020
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I decided against going with the hdmi splitter for a few reasons; I just got a nice new monitor and don't like the idea of something--especially with a power source--in the way of the hdmi cable going from my receiver to monitor; secondly, it's an additional clump of hardware/wires, that lastly I didn't need since all my streaming goes thru an htpc and I just built a new one that was able to include a spdif output.
I haven't tried the digital coaxial again as now that I've played around with the software (nice thing about it all being Asus, the software and hardware play nice together) I've got a pretty nice sound, I think that slight echo sound might've been the room equalizer settings, different areas of the software have it, one states rooms like I tried living room, and another area had settings like theater etc. I selected none for both of those and a 3rd equalizer setting I selected Vocal; in another setting selected balanced, and deactivated reverb all-together. Being a gaming motherboard the audio setup is probably more geared for games, but it's good now.
I will give the coaxial another go later on; but for right now it's working nicely so feel like letting it be for now.
 

Coyle

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May 15, 2020
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Have tried the digital coax and am preferring it; sound is warmer, bass not as dominant--for some reason the optical really does a number on the bass; I've never heard my sub hit such low end bass before which is nice when watching a movie that it's intended to have; but it washed over into the vocals and everywhere. I also gave the RCA a go using the onboard audio and was very disappointed after having gotten used to digital now.