Help putting playback system together, please.

[Sean Connelly]

Hi guys,

First time poster. I'm a HS junior trying to make things work. I've posted these questions in other forums without a single response. I'm hoping someone around here might be able to help. If you want to see the entire back-story, you can follow this link: Help putting playback system together, please?

I'm just posting the Cliff's Notes version here...


After reading endlessly through forums on the net, I think I've answered some of my questions:

The MacMini will not be a good video playback device, especially for Blu-Ray material. I don't think an external USB optical drive is reliable enough. And I don't think any Mac software will decode DVD and Blu-Ray audio and down-mix it to 3.1. A Blu-Ray drive, even with 7.1 analog outs, I don't think will down-mix the audio to 3.1. Besides, commercial Blu-Ray drives are really pricey.

I can take the old PC (originally dual-core, 2 GB ram), which I've already upgraded to 4 GB and Win7, pop a new video card in the PCIe slot (like a Geforce 640) for HDMI connectivity and swap a Blu_Ray/DVD Combo drive for the DVD drive. I can pop a good 1394a card in the PCI slot to move the AudioFire12 over. But that will bypass the Creative driver, meaning, I don't think I'll have anything to decode and down-mix the audio stream. And I don't know of any video playback software that will both decode and down-mix audio.

Questions:

Is there PC video playback software that will decode and down-mix 5.1 & 7.1 audio to 3.1?

Maybe I can use the SoundBlaster, using the S/PDIF (coax or optical) outs, bypassing the on-board D/As?

Will the Creative driver still decode and down-mix the audio using the S/PDIFs?

Is there an inexpensive, external S/PDIF D/A I can use to connect to the PRO1?

If I go with the AudioFire Pre8, losing 8 analog channels (4x4) but gaining a S/PDIF I/O, will I be able to pass a 3.1 audio feed onto the PRO1?


My HS TD keeps telling me that mixing consumer and commercial equipment will only give me headaches. At first, I didn't believe him. What does he know? He's a lighting guy. ;-) But my head is spinning about now. And I need to give my dad a realistic total for this playback system.

Any suggestions?

Thanks!

Sean

 

[Steve Milner]

Re: Help putting playback system together, please.

Hi guys,

My HS TD keeps telling me that mixing consumer and commercial equipment will only give me headaches. At first, I didn't believe him. What does he know? He's a lighting guy. ;-) But my head is spinning about now. And I need to give my dad a realistic total for this playback system.

Sean;
Listen to your teacher.... that is all.

 

[Sean Connelly]

Re: Help putting playback system together, please.

Sean;
Listen to your teacher.... that is all.

Thanks, Steve. I'd love to spend $1k+ on a Blu-Ray deck. But it doesn't work with student's income. Nor do i think it would do what i want it to... How do other people decode and down-mix DTS, True-HD, etc to a 3.1 system?

 

[Brian Bolly]

Re: Help putting playback system together, please.

Thanks, Steve. I'd love to spend $1k+ on a Blu-Ray deck. But it doesn't work with student's income. Nor do i think it would do what i want it to... How do other people decode and down-mix DTS, True-HD, etc to a 3.1 system?

Sean, Steve makes a very good point. Even to do this with a piece of consumer/prosumer hardware is going to run you $1k+.

Most discs give you the option of outputting PCM stereo, or some sort of simplified mix, but in order to even downmix and/or pick off channels, you need to decode it first. The most simplified, idiot-proof way I can think of putting this together is with a decent (pro/pro-sumer) receiver with balanced XLR outputs and let either the playback device or the decoder do the downmixing. Denon makes a nice little box for under $1200 (DN-500AV) that would probably do the trick, in combination of your BluRay player of choice.

 

[Steve Milner]

Re: Help putting playback system together, please.

Dolby Media Decoder? It's $600, but maybe what you're looking for?
I don't think there is a solution that I know of that is gonna be free or cheap... but that doesn't mean one doesn't exist.

I guess my next question would be, if this is a Community theater, with a Midas Pro1 and a new L/C/R speaker & amp install.... why is the video budget dependent on what a high school student can afford? Are you renting them this gear on a per-show or per-season basis? If not, I would not be in a hurry to spend any money. Find the CORRECT solution and present it to them in a professional manner for them to consider in their next round of upgrades.

 

[Dick Rees]

Re: Help putting playback system together, please.

Two sides of the coin:

Heads......look for an inexpensive bunch of gear, try to get it to work together to do what the pro gear will do out of the box

OR

Tails........find a way to earn the money to buy the right piece of gear.

 

[Sean Connelly]

Re: Help putting playback system together, please.

Dolby Media Decoder? It's $600, but maybe what you're looking for?
I don't think there is a solution that I know of that is gonna be free or cheap... but that doesn't mean one doesn't exist.

I guess my next question would be, if this is a Community theater, with a Midas Pro1 and a new L/C/R speaker & amp install.... why is the video budget dependent on what a high school student can afford? Are you renting them this gear on a per-show or per-season basis? If not, I would not be in a hurry to spend any money. Find the CORRECT solution and present it to them in a professional manner for them to consider in their next round of upgrades.

Thanks, Steve.

The "powers that be" do not have a real appreciation for sound. They seem to be happy with stereo playback accompanying video. It's me who thinks it's silly that we don't take advantage of the decent install we have now. My godfather worked for Sound Associates back in the 70's and has taught me a lot about the craft. It's kinda sad that a 17 yo hs student knows more about sound than anyone else in the company. They only really started paying attention to sound after I joined and we started getting feedback from people as to how much the sound has improved...

Maybe it's a wake-up call to reality for me. The professional equipment is way over-kill for what we need to do. I find it kinda crazy that it costs so much more to do what a $300 computer can do. I can currently decode and down-mix the audio stream. The current D/As are fine for our purpose but they're inside a box, surrounded by electronic noise. If Creative made an external, USB sound card with analog 7.1 outs, I could probably make it work just fine. It's not clear if other manufacturers of external cards have the same ability to decode and down-mix... I downloaded the manual for Denon's DN-500AV. Maybe I'm just stupid. But I can't find anything explicit on it's ability to dynamically down-mix multiple channels to feed a 3.1 theater system.

I originally tried to spec a system for all playback using an AES50 interface to the Pro1. That won't work though. Apparently, current drivers won't up-sample playback and I can't send 16/44.1 audio to the interface as the Pro Series only clocks at 24/96?

This seems to be much harder and more expensive than it needs to be. I guess the manufacturers do this on purpose... Maybe a lesson learned.

~Sean

 

[Brad Weber]

Re: Help putting playback system together, please.

About the same response I posted elsewhere but before getting too far into how to get a 3.1 signal into your system you may want to first verify that the existing installed speaker system can properly support a 3.1 signal.

I don't think the analog mixers you apparently used prior to getting the Pro1 supported actual LCR operation and since those are what were being used when the speaker system was installed then it seems unlikely for the system to have been designed and/or programmed as a LCR system, it seems more likely to be stereo plus center mono or even straight mono. Similar for the .1 LFE channel of 5.1 or 3.1 as the installed speaker system would need to be configured for a dedicated LFE or subwoofer input channel and unless you were running aux fed subs then the system may not be setup to work with a dedicated LFE/subwoofer signal.


My understanding is that S/PDIF can carry two channels of PCM audio or multi-channel compressed audio, such as encoded surround going to a surround sound decoder, but I do not believe that a S/PDIF audio stream can carry four discrete channels of decoded audio as you seem to be wanting.

 

[Sean Connelly]

Re: Help putting playback system together, please.

Sean, Steve makes a very good point. Even to do this with a piece of consumer/prosumer hardware is going to run you $1k+.

Most discs give you the option of outputting PCM stereo, or some sort of simplified mix, but in order to even downmix and/or pick off channels, you need to decode it first. The most simplified, idiot-proof way I can think of putting this together is with a decent (pro/pro-sumer) receiver with balanced XLR outputs and let either the playback device or the decoder do the downmixing. Denon makes a nice little box for under $1200 (DN-500AV) that would probably do the trick, in combination of your BluRay player of choice.

Thanks, Brian.

Checked out the DN-500AV manual. No where that I can see does it mention the ability to down-mix multiple channels.

This is what's so frustrating. I can accomplish what I want to do with a $300 computer. But because the D/As are inside the box, I get some noise. Just to move the D/As away from any noise, it's costs 4x more? Balanced outputs would be great but unnecessary for a small community theater. I guess it's just the business model.

~Sean

 

[Brian Bolly]

Re: Help putting playback system together, please.

Thanks, Brian.

Checked out the DN-500AV manual. No where that I can see does it mention the ability to down-mix multiple channels.

This is what's so frustrating. I can accomplish what I want to do with a $300 computer. But because the D/As are inside the box, I get some noise. Just to move the D/As away from any noise, it's costs 4x more? Balanced outputs would be great but unnecessary for a small community theater. I guess it's just the business model.

~Sean

Sean,

I read the Cliffs Notes only prior to my post. Now that I've gone back and read everything on the other site...

I pointed out that Denon unit because that would allow you to take all 6/7/8 channels (albeit analog) into the console on balanced lines and do your own redistribution of content. HOWEVER, Brad raises some excellent points that, until I read the rest of your post on the other site, I didn't see exactly what you were getting at.

Question #1: What exactly are you trying to accomplish with this setup?

You won't find anything in a manual about '3.1 audio' because it's not a real format - it doesn't exist. At best, you may find something about 2.1, but if someone is going to the trouble to encode a multichannel mix that includes discrete center and/or surround tracks (at worst, Dolby PL or PLII), you'd still have a base level Lt/Rt mix that could be played back on a simple set of stereo loudspeakers, no decoder necessary. The fact that your system (for cinema purposes) is likely bass managed as far as the subs are concerned, means you probably don't have a discrete sub input. You could be running subs on an aux, but I won't even get into bass management/bass redirection at the moment.

Question #2: How's your center channel coverage - does it cover every seat in the venue? No? Then you're already running down the wrong path trying to do discrete screen channels.


My point in all of this is that clearly you're doing more multimedia/interactive events and less cinema, which is perfectly fine. But if you plan on using cinematic content, you either need to play by some of the industry conventions with regards to loudspeaker coverage and audio formats, or be prepared to take the decoded 6/7/8 channels of audio and redistribute them to your liking as per the requirements of your event. If you already have a means to extract the multichannel audio (which it sounds like you do), then your best bet to do what you want is burn a bunch of channels to get that into the console and do a couple creative matrix mixes to get it where you need.

 

[Brad Weber]

Re: Help putting playback system together, please.

Checked out the DN-500AV manual. No where that I can see does it mention the ability to down-mix multiple channels.

This is what's so frustrating. I can accomplish what I want to do with a $300 computer. But because the D/As are inside the box, I get some noise. Just to move the D/As away from any noise, it's costs 4x more? Balanced outputs would be great but unnecessary for a small community theater. I guess it's just the business model.

On many surround sound processors/receivers you identify the speaker configuration (side/rear surrounds or not, sub or not, large or small mains, etc.) and the procesor or receiver then automatically processes the incoming signal to the appropriate format.

You may also be overlooking what all is in the boxes and that there is a lot more to it than just D/As. Also, noise and any other potentially related issues related to unbalanced versus balanced audio don't really know or care that it is just small community theater, the same potential issues apply there as anywhere else, it's just how much people are willing to spend to avoid those potential issues.

 

[Josh Millward]

Re: Help putting playback system together, please.

If you are just trying to play back BluRay and DVD content, how about just using a BluRay player that has discrete analog outputs?

You can take the eight output channels (7.1) into your console and down-mix them however you want.

For example you may want to have a look at the OPPO BDP-93:OPPO BDP-93 Blu-ray Disc Player

 

[Sean Connelly]

Re: Help putting playback system together, please.

If you are just trying to play back BluRay and DVD content, how about just using a BluRay player that has discrete analog outputs? You can take the eight output channels (7.1) into your console and down-mix them however you want...

Thanks Josh!

I thought of this. I just don't think myself qualified to do it. I guess it's not rocket science. But how do you best assign side and rear surrounds to the mix? Just route them to the appropriate L or R Channel, leaving the normal FL, FR, C & Subs in their normal positions?

 

[Sean Connelly]

Re: Help putting playback system together, please.

On many surround sound processors/receivers you identify the speaker configuration (side/rear surrounds or not, sub or not, large or small mains, etc.) and the procesor or receiver then automatically processes the incoming signal to the appropriate format.

This is what I'm talking about. Creative Lab Drivers on computers & consumer A/V receivers allow you to make this configuration and dynamically down-mix content. The only thing that's missing is a reliable way to get the down-mixed audio into the console. I don't believe this configuration exists on Blu-Ray Decks however. Consumer receivers are next to useless for this application. Processors seem to be cost prohibitive at my level. I guess this is how the manufacturers protect their commercial markets.

Thanks Brad!

 

[Josh Millward]

Re: Help putting playback system together, please.

Thanks Josh!I thought of this. I just don't think myself qualified to do it. I guess it's not rocket science. But how do you best assign side and rear surrounds to the mix? Just route them to the appropriate L or R Channel, leaving the normal FL, FR, C & Subs in their normal positions?

Honestly, I think it has more to do with practice and content than anything else. You can layer some of the surround and back surround into the Left and Right mains, but always leave the Left, Center, and Right channels panned hard out to those loudspeakers (unless your main loudspeakers do not fully cover the listening area, then you may have to collapse the stereo imaging and fan out the center channel a bit to get proper coverage everywhere...)

This is also highly dependent on the content. Sometimes you should probably just nix the surround info, others you should layer it in below the main content... you may also want to delay to the inputs a bit to differentiate them... it is something I would play with and there aren't any set rules because as was mentioned earlier "3.1" isn't really a format.

Just play with it and see what sounds the best. Your first trick is going to be getting all those channels off of the disc and into your console.

The OPPO BDP-93 is a great unit, I have one in my home system and there are a couple of them that we use for trade shows quite regularly at work.

 

[Sean Connelly]

Re: Help putting playback system together, please.

Well guys,

I may have come up with the solution I can sell to the theater. After reading through manuals of every Blu-Ray player with 7.1 analog outs, I found the Panasonic DMP-BDT500. If I'm reading the manual correctly, it will decode and downmix 7.1 to basically any speaker config you enter, based on number, placement, size, etc. I'm stuck with RCA outs. But the deck lives three feet from the console. And I haven't had any issues with the unbalanced cables currently carrying the stereo PCM. B&H is selling it for $277 and change. I think I can sell this. Can anyone confirm the decoding/downmixing capabilities of this deck? http://service.us.panasonic.com/OPERMANPDF/DMPBDT500-MUL.PDF The Audio section starts on page 29. "Analog Audio Output" is on page 30.

As far as speaker coverage goes... According to the EASE data I was shown, 92% of our 399 seats is covered +/- 3dB with L/C/R/Subs the remaining 2% is +/- 5 db. I've run pink noise through all channels separately and my ears tell me it's reasonably even too.


Thanks!

Sean

 

[Brad Weber]

Re: Help putting playback system together, please.

I may have come up with the solution I can sell to the theater. After reading through manuals of every Blu-Ray player with 7.1 analog outs, I found the Panasonic DMP-BDT500.

Just remember that any current Blu-Ray player models have to use digital video for HD and because the next step in the Analog Sunset is at the end of this year and requires eliminating analog video outputs entirely, many current models do not have analog video outputs. So your projector may have to support HDMI.

Looking at the referenced manual all I see discussed is a two channel downmix, I did not see 3.1 specifically addressed. Not an area I follow that closely but from what I gather the digital surround formats do not specifically address a 3.0/3.1 downmix, typically addressing a stereo downmix, 5.1 and 7.1. Any downmixing of 5.1 or 7.1 to 3.1 is apparently up to the hardware manufacturer to implement.

As far as speaker coverage goes... According to the EASE data I was shown, 98% of our 399 seats is covered +/- 3dB with L/C/R/Subs the remaining 2% is +/- 5 db. I've run pink noise through all channels separately and my ears tell me it's reasonably even too.

How you select what is being displayed, the calculation basis, how well (or if) the room is modeled, etc. can provide very different results in EASE and since I have seen that abused, I don't put much faith in EASE results unless you know what they are showing. That being said, the fact the some modeling was performed says something and your listening results say a lot more.