[hometheaterguy]

Tom Holman liked the height channel idea. Follow this site for a diagram:

http://www.hometheaterhifi.com/qa/qa2002/qa296.html


I am considering installing two front height speakers played full-range if it does not screw up the panning, imaging and sound stage of my main L, C, and R. I would wire them on a 2-channel amp off of my Lexicon AUX stereo front outs.


Has anyone tried this to achieve more realism? Is it detrimental?

 

[sdurani]

Scott,


What info are you going to feed those height speakers?


Sanjay

 

[hometheaterguy]

What's up Sanjay. If I did go the height route I would experiment feeding them full-range from the AUX outs on my CP-1. I also would try using a sum adapter with the processed center channel. I thought of one more thing: using just tweeters for the heights and crossing them over above 5000Hz to create a psycho-acoustic height effect. Again, I am seeking wisdom on this. My gut feeling tells me to KIS (keep it simple), but others like Yahama believe in the height theory. IMAX can get away with a discrete height center channel because the steep stadium seating design and large cubic foot theater room. The way I see this height theory is if it improves the WOW Factor and realism it is worth the shot.

 

[Dennis Erskine]

What you're missing is Holman's 10.2 proposal is for discrete height information channels. (Height channels are also a part of the Ambisonic format.)


Yamaha, uses a DSP process they've refined over the past 15 years to create "discrete" sonic information for their height channels to create a proper height cue while minimizing distortion effects from comb filtering.


The path that you propose will not add 'height' cues, will adversely impact the sound stage plus create distortion artifacts due to phase/path differences.

 

[hometheaterguy]

Dennis, it is always a joy hearing from you. I thought not having discrete processing would be detrimental to the front sound staging. I just wanted another opinion before I tried to make a height channel. Someone should invent and patent a black box height channel unit that can be added to receivers, or prepros. I am surprised Lexicon prepros have not yet incorporated a height effect channel in their design. Perhaps someday they will.

 

[BGLeduc]

Quote:

Someone should invent and patent a black box height channel unit that can be added to receivers, or prepros. I am surprised Lexicon prepros have not yet incorporated a height effect channel in their design. Perhaps someday they will.

What's so hard about that?


Why could that not be matrixed between the Left and Center, and the Center and Right. You could even go further and use PL steering to give you a hard 1/2 left and 1/2 right AND a mono height channel per side.


Thats how we get a back surround and a rear height channel now (excluding of course DTS that has a discrete back channel).


Of course, it would be a crap shoot to do this without software that was encoded to take advantage of it, but you could try it today with a pair of the surround boxes that WSR has reviewed (don't recall the name...is it SMART systems CS?).


They used them in an article to do SDDS in a HT environment, although they were not doing the height channel, just a hard 1/2 L and 1/2 R.


Speaking for myself though, at 6.1, I think I have enough speakers in my room as it is


BGL

 

[hometheaterguy]

If I develop it, I will share some of the profits with you

 

[BGLeduc]

Quote:

If I develop it, I will share some of the profits with you

While I will of course share in the profits, I guess my point is, the hardware already exists. Its just encoding the software that is needed, and even that can be done with existing techniques and hardware.


Of course, if you want to go discrete, thats an entirely different kettle of fish.


But, I still lack space for another pair of fronts! Perhaps with the profits, I can buy a bigger home?


BGL

 

[hometheaterguy]



 

[Dennis Erskine]

I suppose it could be matrixed; however, it would take some serious DSP processing (Yamaha currently is the only one doing this and with proprietary logic chips) to extract the "height information". Understand, we're not just putting speakers up high...we have to determine what sounds would logically come from that direction (psychoacoustically), and then steer those sounds without artifacts, etc.

 

[Terry Montlick]

BGLeduc:


Excellent idea about matrixing height channels! I love it. The effect of a height channel is quite spectacular, at least for large screens/close viewing distances.


It's amazing that IMAX works so beautifully with only one height channel. They do some serious panning of sound sources, up and down as well as left and right. It's commonplace among IMAX sound mixers. You can practically point to the spot on the screen where the sound appears to come from. Feature film mixers have a different culture, and tend to get stuck in the old "dialog goes to center channel" mindset, with a minimum of panning.


I'm all for starting a de-facto standard such as this. Old pro-logic encoders/decoders could simply be added between L/C and R/C channels. Now all you have to do is interest a major motion picture distributor and a chain of movie theaters!


Nonetheless, I think that such a scheme has much better commercial prospects than 10.2, which requires all new equipment and encoding. Studios and exhibitors are still trying to get their money's worth from their 5.1 investments. They definitely don't want to toss out all this "old" stuff.


Regards,

Terry

 

[sdurani]

Quote:

Originally posted by BGLeduc Why could that not be matrixed between the Left and Center, and the Center and Right.

I agree: there's no reason it can't be done. After all, any pair of discrete channels can hold additional channels matrixed in (which can be recovered upon decoding). The problem is whether there's more than a niche interest for additional channels, and whether it's worth it to the studios.
Quote:

Of course, it would be a crap shoot to do this without software that was encoded to take advantage of it, but you could try it today with a pair of the surround boxes that WSR has reviewed (don't recall the name...is it SMART systems CS?).

Crap shoot indeed. WSR promoted the CS boxes as capable of recovering height information from DVDs. One problem, there aren't any DVDs (zero, zip, nada) with height info encoded into the mix. The sounds that those boxes extract might be pleasing to listen to, but they aren't what WSR claims they are.
Quote:

They used them in an article to do SDDS in a HT environment, although they were not doing the height channel, just a hard 1/2 L and 1/2 R.

The SDDS article was interesting. Again, those CS boxes extracted 1/2 Left+Centre and 1/2 Right+Centre. One problem, when SDDS soundtracks are downmixed from 5 front channels to the usual 3 front channels, the additional 2 channels are mixed with 2/3 going to the Centre and 1/3 going to their respective Left or Right channels. This is understandable because SDDS's 2 additional front channels are basically dialogue channels. So, once again, whatever the CS boxes were extracting may have been pleasing to the ears, but it wasn't the lost SDDS channels that WSR claimed it was.


Best,

Sanjay

 

[BGLeduc]

Quote:

I suppose it could be matrixed; however, it would take some serious DSP processing (Yamaha currently is the only one doing this and with proprietary logic chips) to extract the "height information".

With properly encoded software, no DSP would be needed, just a good 'ole PL (aw, what the hell, lets do it right) PL II decoder.


But with existing software, yup, I would agree with the need for some major league DSP.


I guess me viewpoint would be that without software encoded for the purpose, any channel extraction scheme, no matter how pleasing it may be to listen to, would be a guess. Some guesses (Yamaha's perhaps) are likely to be better than others, but I still would question the value of adding the extra channels w/o software tweaked for the purpose.


Personally, while I don't expect to have room for a 10.2 system in my home anytime soon, I agree that discrete channels are the way to go.


For now, I will have to suffer (!) with 6.1. The HORROR!!!!!!


BGL

 

[hometheaterguy]

There is always new surround sound formats on the drawing board, it's just a matter of when it will be implemented to the home market. The commerical theater always sets the standards.