State of the art Home Theatre - how?

[Dave Zan]

Like a lot of people on this site, I am amazed that there is no really State Of The Art home theatre solution.
Even $17,000 AV processors perform far worse than a $100 DAC.
I would love to have some input on how could we do a SOTA HT.
For a stereo system it's not too hard - with AES outputs we can do all the equalisation and crossover before the DAC.
Plenty of nice DACs with >120 dB performance.
Active speakers and we're done.

For home theatre with active speakers we end up with a lot of channels if we have 7.1 or more system x 2 or 3 way.
But a harder problem is the source material, we seem more or less stuck with an AVR for all the licenses for the latest Dolby and DTS lossless CODECs.
And the onboard DAC implementation in even the most expensive is not SOTA.
And the license rules mean no accessible PCM streams we can send to be equalised, crossed-over and then DACed in a SOTA DAC.

So far the best approach seems to be to use the excellent @Weeb Labs videos to hack an AVR to extract the I2S streams, possibly convert to AES.
Once we have I2S or AES then what?
We need volume control, usually done in the AVR after the DAC AFAIK.
So a multichannel DAC with volume control, maybe the Okto 8 once it becomes re-available.
But for multi-way active speakers, can multiple units be tied to work in unison?
What about the DSP and crossover?
Does this sound like a project anyone else would be interested in?

David

 

[Vincentponcet]

The easiest way is files on a PC, then you use any USB multichannel DAC.
I tried AppleTV (because it does HDMI LCPM decoding) + meridian HD621 for having HDMI to SPDIF then DAC8PRO, but probably the signal level of the meridian makes dropouts on the DAC8PRO, so I have to try to use the RJ45 AES wires to AES/XLR plugs.
When you tried real BD UHD, it is difficult to go back to streaming sources, the gap is massive, on video and sound.
On video, streaming is more grainy with artefacts, but sometimes, streaming have DV when BD only have HDR10.
On sound, streaming best quality is dolby digital plus 640kb/s, when you have lossless on BD UHD.

 

[beren777]

I think it's important to first consider what one wants to achieve , what "state of the art" really means, and where the cliff is for price vs performance. Many of us would not be able to tell top tier a DAC from a "good tier" DAC, even before processing and speaker differences. The differences are measurable on the test bench but your ears aren't as sensitive as an APx555. I feel it's good to strive towards transparency but once you're outperforming your ears (or more generally, the ears of your expected or average audience), you're spending money on vanity, not performance.

"SOTA HT" should also encompass video and human comfort. Your equipment can be top tier but if the room is a triangle or perfect square with bench stools for seats people may not enjoy the experience. A "SOTA HT" playbook should include basics on room layout for comfort and performance, cable routing, etc.

Personally, for the AVR portion, I'm doing alright with a horribly-measuring Marantz AVR. I plan to upgrade in the next few years to something that measures effectively transparent, doesn't mangle the audio or video, is stable, and includes Dirac room correction, like the Monolith HTP-1 if they fix some of its issues. But that's $4,000. I might better elevate my HT towards SOTA if I spent that money on the room, a better center channel speaker (looking at you, Revel 426 Be), or another subwoofer.

 

[GXAlan]

For streaming, audio is lossy so I doubt you need anything more than a X8500H.

For lossless audio with physical media, you are generally dealing with 24/48.

Your best bet is spending the money on an Oppo 205 or a Panasonic UB9000. The Oppo’s HDMI in has some great advantages too, and it’s pretty clear that it was underpriced and that the current value reflects true market value. The Panasonic UB9000 has a lot of strengths such as a quieter mechanical disc player. This works for 2 ch high resolution content protected playback.

All that said, for the movies with object oriented Atmos, we don’t have a lot of good options.

 

[abdo123]

For electronics, I'm happy with whatever device I have as long as it doesn't hiss where i'm sitting at night.

 

[andymok]

Get your room built right first. Then alignment. Then we talk about hardware.

 

[Weeb Labs]

We need volume control, usually done in the AVR after the DAC AFAIK.
David

Handling the volume control should be fairly straightforward. Most AVRs make use of an NJW1194 or similar, which leaves us with several possibilities.

The simplest and most universal solution is to loop the ADC of a microcontroller through one of the onboard NJW1194's channels and use those values to drive an external quadVol board. A less universal apprach would be to extend the onboard NJW's I2C lines to an identical external IC on the same address.

Both of these options would enable the AVR to retain functional volume control.

 

[JeffS7444]

I realize that people like to fixate on DACs and amps, but even mediocre products on the wrong end of ASR's SINAD chart may be essentially transparent to the listener. And the reason you might want a "crummy " mid- or lower-priced AVR is because that's where some of your biggest values are. Today, Dolby Atmos and HDR video are the big selling features, but sooner or later, something else will come along, and it's so much easier to upgrade a single $600 box every decade or two.

I figure that even if my money and space were unlimited, why add pointless complexity to my life? Sometimes I just want to watch a movie and not spend 20 minutes initializing and troubleshooting the hardware.

 

[Weeb Labs]

I figure that even if my money and space were unlimited, why add pointless complexity to my life? Sometimes I just want to watch a movie and not spend 20 minutes initializing and troubleshooting the hardware.

This type of project will not appeal to everybody and that is absolutely fine. For some, it is simply the fun of creating a niche device which is not otherwise available.

 

[Dave Zan]

I realize that people like to fixate on DACs and amps...

Yes, as you say people do tend to fixate on one particular item - DACs or capacitors or the cables or whatever.
What's funny is that frequently it's not even an item that makes much difference.
That was not my point, even if I have to admit that when I reread my post I can see it's not as clear as I wanted.
The issue is that even a ridiculously expensive AVR can't match a cheap non-AVR component in performance.
That component just happened to be a DAC.

...want a "crummy " mid- or lower-priced AVR is because...

Yes, I don't want to buy a ridiculously expensive AVR even if it had SOTA performance.
I want a mid or lower priced AVR solution that has performance that matches the state of the art in non-AVR components of equivalent price.
I say "equivalent" because I realise an AVR solution has more channels and obviously there are extra costs.
But not only are they disproportionately more expensive, they don't even work well.
When even low cost electronics can reach SINAD that is utterly transparent it annoys me that even the most expensive AVR is so much worse.

...even if my money and space were unlimited, why add pointless complexity to my life?

The elimination of pointless complexity is exactly what I want to achieve.
For instance, I don't see any point in an AVR that does DA conversion, that is then sent to speaker DSP that immediately does AD conversion back to where we started.
At best it's pointless and if the initial DACs are poor then it's worse.
So the idea is a better architecture, not necessarily a better DAC.
If I can unload the speaker and room DSP into a separate box then the AVR can be simple.
And, as you say, replaced cheaply when obsolescent.
If the speaker DSP doesn't need an ADC then it's simpler and cheaper.
That would be a technically better way to factor the system than the current AVR approach.
It's more modular - more easily expandable, more maintainable.
The reason it's not done is only for the benefit of the corporate bottom line, not the customer.
That annoys me and it's inspired me to try to find a neater implementation.

...Most AVRs make use of an NJW1194 or similar, which leaves us with several possibilities....

The NJW1194 isn't bad but not quite up with the best DACs.
I wonder if it contributes to the usual less than stellar AVR measurements?

Thanks for both the help and the appreciation of what I want to achieve.

Best wishes
David

 

[Weeb Labs]

The NJW1194 isn't bad but not quite up with the best DACs.
I wonder if it contributes to the usual less than stellar AVR measurements?

I don’t believe so. At unity gain with 2Vrms input, shmoo is approximately 96dB down. This would discount it as a likely bottleneck, although you are correct in that it falls short of many DACs.

The alternative is a pair of PGA4311UA, which is what I have been using on two qualVol boards. It is one of the highest performance options available but requires an intermediary MCU in order to derive the appropriate values from the AVR.

 

[JeffS7444]

I want a mid or lower priced AVR solution that has performance that matches the state of the art in non-AVR components of equivalent price.
...
When even low cost electronics can reach SINAD that is utterly transparent it annoys me that even the most expensive AVR is so much worse.

For the most part, today's AVRs are capable of transparent sound reproduction, in the sense that frequency response is flat, noise is low, and distortion is typically below 1%: This may not please the intellect, but the ears aren't so discerning. But hopefully bench-test reviews like Amir's will encourage manufacturers to be more meticulous.

But not only are they disproportionately more expensive, they don't even work well.

The typical 7.1-channel AVR is very cheap considering that it has 8 channels of audio and includes room correction, Dolby and DTS licensing, HDMI switching, Bluetooth, audio streamer, radio, and power amplifiers. And the price needs to be competitive, because it's now competing against mobile devices! Today, I suspect that "Home Cinema" for many people is a 55" TV set, their phone, and wireless headphones. No AVR, no speakers.

Reliability of my Marantz NR1608 hasn't been perfect, but, knock on wood, I think I've solved the problem of intermittent headphone output by applying contact cleaner to the headphone jack and some of the internal connections. I shouldn't need to do this on a late-model receiver, but for the most part, it works very well with no glitchiness or random loud burst of noise

 

[phoenixdogfan]

Like a lot of people on this site, I am amazed that there is no really State Of The Art home theatre solution.
Even $17,000 AV processors perform far worse than a $100 DAC.
I would love to have some input on how could we do a SOTA HT.
For a stereo system it's not too hard - with AES outputs we can do all the equalisation and crossover before the DAC.
Plenty of nice DACs with >120 dB performance.
Active speakers and we're done.

For home theatre with active speakers we end up with a lot of channels if we have 7.1 or more system x 2 or 3 way.
But a harder problem is the source material, we seem more or less stuck with an AVR for all the licenses for the latest Dolby and DTS lossless CODECs.
And the onboard DAC implementation in even the most expensive is not SOTA.
And the license rules mean no accessible PCM streams we can send to be equalised, crossed-over and then DACed in a SOTA DAC.

So far the best approach seems to be to use the excellent @Weeb Labs videos to hack an AVR to extract the I2S streams, possibly convert to AES.
Once we have I2S or AES then what?
We need volume control, usually done in the AVR after the DAC AFAIK.
So a multichannel DAC with volume control, maybe the Okto 8 once it becomes re-available.
But for multi-way active speakers, can multiple units be tied to work in unison?
What about the DSP and crossover?
Does this sound like a project anyone else would be interested in?

David

I'm already pretty far along. I have a 4.1 using 4 LS 50s (fronts are Metas), an Sb2000, Octo 8, and an i7 running JRiver with Dirac Live 3. I just got the Octo last week, and finally got everything hooked up. It works. Still have to dial it in. I also have a two channel use case, and I'm using the Dephonica software crossover (which is freeware) for that. I also have it working. Obviously this is limited to a 7.1 system. Beyond that, the codec makers hold an iron fist on copyrights (ATMOS, DTS-X, Auro 3D) and will not license them for anything other than dedicated processor/receivers which are both uber expensive, and have mediocre performing dacs and amps.

JRiver and Octo are your very best friends in this endeavor. I will be publishing details in the days ahead. I am still dialing in the settings, and I have not yet created Dirac live filters for each of the use cases. Already it sounds awesome, though. Amplifier is the Purifi Eval 1. Will keep you posted.

BTW, something like the Motu Ultralite Mk 5 would probably work in place of the Octo, and be both cheaper and more available--but no remote, unfortunately.

The HP 12c avatar takes me back to my days in B-School.

 

[tifune]

The easiest way is files on a PC, then you use any USB multichannel DAC.

BTW, something like the Motu Ultralite Mk 5 would probably work in place of the Octo, and be both cheaper and more available--but no remote, unfortunately.

I'd really like to take this approach, but I have yet to find a good answer for more than 8 channels. 13-15, like 6700/8500 for example? Even Universal Audio's x16 lists "up to 7.1" in the specs.

 

[Blumlein 88]

https://gracedesign.com/products/monitor-controllers/m908

This can likely let you get some good s.o.t.a sound even in Dolby Atmos. It is expensive to be sure. Does the decoding, has built in DSP and can do room correction for each monitor for up to 24 monitors.

 

[MenloBob]

https://gracedesign.com/products/monitor-controllers/m908

This can likely let you get some good s.o.t.a sound even in Dolby Atmos. It is expensive to be sure. Does the decoding, has built in DSP and can do room correction for each monitor for up to 24 monitors.

I think my pocketbook is going to be sad you pointed this out...

 

[Vincentponcet]

https://gracedesign.com/products/monitor-controllers/m908

This can likely let you get some good s.o.t.a sound even in Dolby Atmos. It is expensive to be sure. Does the decoding, has built in DSP and can do room correction for each monitor for up to 24 monitors.

There are no software to decode Atmos on PC, object based codecs are only available in pre/pro AVRs.

 

[Vincentponcet]

I'd really like to take this approach, but I have yet to find a good answer for more than 8 channels. 13-15, like 6700/8500 for example? Even Universal Audio's x16 lists "up to 7.1" in the specs.

Because there are no software decoder supporting more than 7.1 on PC.
No Atmos, no auro3d or DTS:X
You can use a DSP to spread 7.1 over more speakers.
If you want 16 outputs, you can take 2 boxes making 8 outputs and joining them as one virtual device of 16 outputs.
There are virtual drivers doing this, probably even asio4all.
Some professional boxes drivers do it.

 

[Sancus]

The issue is that even a ridiculously expensive AVR can't match a cheap non-AVR component in performance.

I'd argue the opposite, actually. All those DACs with no EQ or room correction are useless, even relatively cheap AVRs include these baseline requirements for good sound. And they trick people into thinking SINAD of 95 vs 115 matters when it doesn't matter at all.

 

[markb]

So far the best approach seems to be to use the excellent @Weeb Labs videos to hack an AVR to extract the I2S streams, possibly convert to AES.
Once we have I2S or AES then what?
We need volume control, usually done in the AVR after the DAC AFAIK.
So a multichannel DAC with volume control, maybe the Okto 8 once it becomes re-available.
But for multi-way active speakers, can multiple units be tied to work in unison?
What about the DSP and crossover?
Does this sound like a project anyone else would be interested in?

This is essentially what I am trying to do as well with my Genelec SAM monitors. They can take care of D/A conversion, bass management, crossover, room correction and volume control, except that the interface to control that (GLM and their USB adapter) is a bit too inflexible. I am writing python code to address that and be able to hook them up with my home automation setup and arbitrary hardware and software for volume control, source selection etc. The active monitors indeed work in unison; through a single broadcast command on the GLM network for e.g. volume setting they all act the same.