HDMI isilencer

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Shopping for HDMI or thunderbolt cables is a minefield these days! You read the fine print and discover the "HDMI cable" is only rated for a lower bit rate. Or you find a thunderbolt cable is only rated for displayport use. Or you get the properly rated one (allegedly) and the quality is on the edge enough that it crosses that threshold and fails soon.

Subwoofer speaker wires? I would absolutely use at least 16AWG unshielded wire for that. Bass frequencies pushed out of a power amp for a subwoofer carry some current! RCA cables not so much. (If we're talking about the speaker cables and not the line level connection to the subwoofer amp input.)
 
Subwoofer speaker wires? I would absolutely use at least 16AWG unshielded wire for that. Bass frequencies pushed out of a power amp for a subwoofer carry some current! RCA cables not so much. (If we're talking about the speaker cables and not the line level connection to the subwoofer amp input.)
Line level is what I was referring to. Self powered subs. Without shielding you're subject to pick up interference.
Some subs have provisions to have speaker cable input on the line level. (well not the better ones).
Some subs with two line level inputs you can allegedly utilize both to deliver more signal to the sub (haven't tried it).

Although I think the output from my sub is adequate, I've sometimes thought about running a Y cable from the AVR's dual sub outs. Internally on my AVR they tied together so IDK what difference it would make, if any, not having knowledge of the circuitry in the AVR.
 
Line level is what I was referring to. Self powered subs. Without shielding you're subject to pick up interference.
You can also use balancing adapters and make the long runs with balanced cables (XLR for this example).
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Note that you may see some low frequency rolloff, but this can be compensated with correction at either end (if your AVR/pre-pro and/or subwoofers support it).
 
LOL... Be careful, Unlike other streamers, Kaleidescape does stream completely uncompressed files said to be the equal of 4k Bluray or whatever is the best available at the time. It requires very dedicated gear and is quite expensive. If your a huge home theater movie buff, worth the cost I guess.
Well so does the decade-old Windows laptop I've got sitting on the floor, just playing streams from a .iso or an MKV file with zero conversion. Not for everyone, but I can't fathom the amounts people are willing to pay just to not use a real computer. Could run HDMI and ethernet through your wall for less if you really hate seeing cables out.
 
Well so does the decade-old Windows laptop I've got sitting on the floor, just playing streams from a .iso or an MKV file with zero conversion. Not for everyone, but I can't fathom the amounts people are willing to pay just to not use a real computer. Could run HDMI and ethernet through your wall for less if you really hate seeing cables out.
I think Kaleidescape users are the ones that are averse to buying a bunch of discs, not averse to using a PC. Discs take up space, and if you don't got a whole lot, streaming may be a better option!
 
If it's intercepting the signal and reprocessing, I'd like to know what it is actually doing, is all.
Well not going to beat a dead horse here, since apparently no one knows what is actually happening or what sort of circuit is involved.
Pretty straightforward question.
Kind of telling when you get defensiveness in answer, right?

The sample rate clock running the DA converter you are listening to being stable and jitter free leads to the best DA performance. Kind of obvious... unstable jittery clock ticks would smear the audio time-wise. Back in the days when some early digital converters had less than optimal clocks, an upgraded sample rate clock led to better DA playback performance.

Digital audio shuttled between devices is a moot point. As long as all the ones and zeros get there... mission accomplished! It's the DA converter we're listening to the audio from and that's the clock that needs to be jitter free. The in-between device data shuffle can jitter around, pause and lag as it pleases as long as the data gets from point A to B in time.

So when someone comes along talking about DA converter clock jitter but tries to superimpose that discussion on data transmission between devices with HDMI with no connection to the DA sample rate clock in any way... well, there will be questions!

When the answer is defensiveness and changing the subject... there ya go! Listeners being subjective is nothing new. I've heard people listening to dropout riddled digital audio systems and appearing oblivious to anything wrong. Not jittery. Not occasional error correction warbles. Straight up mutilated audio clicking and popping away with abandon. Forgive me for not taking such a person's critique seriously, right?

We're all listening if someone has discovered a cheapness element in some products that has a slick cure! Or whatever the premise might be. I can just buy that cheaper one and then one of those thing? Ya, I'm listening!! So far only defensiveness or changing the subject in answer to any questions.

People like the sport of busting someone on the internet. Someone would have recorded the output before/after this thing and posted spectrogram plots if there was anything to show.
 
Well so does the decade-old Windows laptop I've got sitting on the floor, just playing streams from a .iso or an MKV file with zero conversion. Not for everyone, but I can't fathom the amounts people are willing to pay just to not use a real computer. Could run HDMI and ethernet through your wall for less if you really hate seeing cables out.
I'm with you on that. My pc's are my primary playback devices: and I always rip to .iso.
I know people like to make their playlists and such, and a lot of people rip to flac or other containers and look at art like in Kodi.
I just rip to .iso and get the whole 9 yards at once. The little bit I have to wait for the music to begin in some cases doesn't bother me.
 
Pretty straightforward question.
Kind of telling when you get defensiveness in answer, right?

The sample rate clock running the DA converter you are listening to being stable and jitter free leads to the best DA performance. Kind of obvious... unstable jittery clock ticks would smear the audio time-wise. Back in the days when some early digital converters had less than optimal clocks, an upgraded sample rate clock led to better DA playback performance.

Digital audio shuttled between devices is a moot point. As long as all the ones and zeros get there... mission accomplished! It's the DA converter we're listening to the audio from and that's the clock that needs to be jitter free. The in-between device data shuffle can jitter around, pause and lag as it pleases as long as the data gets from point A to B in time.

So when someone comes along talking about DA converter clock jitter but tries to superimpose that discussion on data transmission between devices with HDMI with no connection to the DA sample rate clock in any way... well, there will be questions!

When the answer is defensiveness and changing the subject... there ya go! Listeners being subjective is nothing new. I've heard people listening to dropout riddled digital audio systems and appearing oblivious to anything wrong. Not jittery. Not occasional error correction warbles. Straight up mutilated audio clicking and popping away with abandon. Forgive me for not taking such a person's critique seriously, right?

We're all listening if someone has discovered a cheapness element in some products that has a slick cure! Or whatever the premise might be. I can just buy that cheaper one and then one of those thing? Ya, I'm listening!! So far only defensiveness or changing the subject in answer to any questions.

People like the sport of busting someone on the internet. Someone would have recorded the output before/after this thing and posted spectrogram plots if there was anything to show.
Yes.
When a stated device is carrying out some function, but with no explanation how it's done, I just have to wonder what exactly is the device doing?
Is it quantifiable?

I mean I don't want to bust anyone's chops, just want to know how these devices actually work.

People like what they like: I want to know how/why something works. Just saying a device "reduces jitter" which has already been pointed out as claims made in the past by one entity or another, just doesn't cut it for me. If it works for others then fine.

What was the last upgrade in recent years that made the most difference in sound to anyone? Was it the electronics or was it speakers? I personally would believe speakers and/or a decent room calibration.

But I'm ready to be proven wrong with an explanation on how these devices actually work. I don't think I'll get one, though.
 
HDMI passes data over 3 serial data lines along with a clock, all 4 are differential twisted pair signals and should be shielded (this minimises noise pick-up and emissions). The serial data streams have 8b/10b or 2b/10b error correction, which correct most errors. The audio is Packetised and Time Division Multiplexed into the non-active spaces on the video lines (so set by the resolution of the video), it is not continuous. It should be sent over the Data Island periods (Dark Blue).
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eg.
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The audio is clocked at the data rate of the video bit rate, and is extracted and loaded into a buffer in the HDMI receiver chip where it is read out at the required audio data rate, it is not the same clock so any jitter on the HDMI data stream is irrelevant. If there is Jitter present on the signal then it is either catastrophic so your HDMI picture and audio would break up, or it adds a minute amount of audio or video noise.
 
HDMI passes data over 3 serial data lines along with a clock, all 4 are differential twisted pair signals and should be shielded (this minimises noise pick-up and emissions). The serial data streams have 8b/10b or 2b/10b error correction, which correct most errors. The audio is Packetised and Time Division Multiplexed into the non-active spaces on the video lines (so set by the resolution of the video), it is not continuous. It should be sent over the Data Island periods (Dark Blue).
View attachment 112962 eg. View attachment 112963View attachment 112965
The audio is clocked at the data rate of the video bit rate, and is extracted and loaded into a buffer in the HDMI receiver chip where it is read out at the required audio data rate, it is not the same clock so any jitter on the HDMI data stream is irrelevant. If there is Jitter present on the signal then it is either catastrophic so your HDMI picture and audio would break up, or it adds a minute amount of audio or video noise.
Are the packets analogous to TCP-IP, where packets are sent, and a return response is sent?
 
Are the packets analogous to TCP-IP, where packets are sent, and a return response is sent?
No return responses, its a one way trip! There is to-&-fro comms with the EDID channel which sets up the interface between the two connected devices - which is why you sometime get audio mutes between a TV and AVR even when the TV is switched off.
 
The only time I have problems with my AVR is it does not switch between inputs super fast. Normally, once the handshake is over it works pretty good between the pc and AVR.
I notice this mostly with the pc's and not the disc players or other inputs.
I have this weird Asus motherboard that one has to go into the BIOS once in a while, select for all settings to be set to default, reboot, then reconfigure the options. But this is only for the onboard HDMI port. The Nvidia card just works.
 
HDMI passes data over 3 serial data lines along with a clock, all 4 are differential twisted pair signals and should be shielded (this minimises noise pick-up and emissions).
My friend hinted that Dr Who passes each and every Isilent widget thru his Tardis Timey Wimey Syncrowave 2000 clock. Only 3 of these are said to exist now since the destruction of Gallifrey.
 
Given how with HDMI the audio and video data is packed together it is amazing that it works at all! The wonder of digital technology!

This makes me rethink the purpose of the true-audio button on higher end machines. While I have always thought it to be a good idea to kill the video circuits while listening to music (to eliminate the possibility of any video induced noise) but I have never actually noticed any difference/improvement in sound quality at least while using the analogue outputs. I just wonder if it would be a factor at all with HDMI, that is where "noise" from the video might possibly affect the audio signal.

Now you "digital is perfect people" don't bit my head off, I was just musing over this idea.
 
The only HDMI cable I had fail was a Monoprice 50' active-optical that took a lightning hit.
Monoprice replaced it under warranty with no questions asked. (thankfully LOL)
I had a 40’ cable die after five years or so. It was run through an unheated area. The optical cable I teplaced it with died within the warranty period from Amazon and there’s another passive cable working OK so far.

I had a couple of cables in my stack/rack die as well. Running from the cable box to the pre-pro. No unusual flexing, but some that I’ve been careful to minimize.

And I’e never had any of my analog cables fail. I make those myself out of S-video cable stock and gold-plated connectors.
 
Given how with HDMI the audio and video data is packed together it is amazing that it works at all! The wonder of digital technology!

This makes me rethink the purpose of the true-audio button on higher end machines. While I have always thought it to be a good idea to kill the video circuits while listening to music (to eliminate the possibility of any video induced noise) but I have never actually noticed any difference/improvement in sound quality at least while using the analogue outputs. I just wonder if it would be a factor at all with HDMI, that is where "noise" from the video might possibly affect the audio signal.

Now you "digital is perfect people" don't bit my head off, I was just musing over this idea.
Highly unlikely.

If the internal power supplies on the player aren't adequately filtered then that and cross-talk/internal radiated emissions are the most likely route for noise to get into the analogue audio channels, so switching off the video might improve that, but if its been properly designed you wouldn't notice - most things like that come from marketing saying competitor X does it why don't we!
 
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