5.1 and beyond......?

[Bus_Boy]

Hello again

We are moving into a 4 bedroom house shortly, and i am planning on building a cinema room on a budget . I plan on using my current diamond 9.5's as fronts, and buying the 9C centre and either the 9.1's, or 9.4's for the rear.

I've been looking at receivers, and something i don't quite understand is the amount of channels that some amplifiers have these days. I'm familiar with 5 ch, but some go right up to 13 channels, and anything in between.

So what do the extra channels do, and where do the speakers go? Is it worthwhile going for a receiver that has more than 5 channels, or should i just look at getting the best receiver i can afford with the bare minuimum 5.1.

I don't mind so much if it's just a matter of adding additional speakers, given the price that you can get the Wharf 9.1's for these days, it's hardly going to send me broke if i slowly add additional pairs over a period of time.

I'm thinking though more along the lines that the average room would benefit more from better placement and acoustic treatment, as apposed to just jamming in as many speakers as the room will take:confused:

Edited April 16, 2011 by Bus_Boy

[emesbee]

What do the extra channels do? Make you buy more speakers!

Actually, I think you summed it up in your last sentence. I reckon consider the room dimensions first before deciding on speakers.

In any case, how many channels are recorded on DVD or BluRay discs these days? I'm not up with the latest developments/trends in home theatre, but I thought 7.1 was the limit.

[Craigandkim]

Emesbee,

you are quite correct there is a max of 8 channels for blu-ray.

BB,

a similar topic has been discussed here

Have a look at the database reference the amount of 7.1 titles available here

Depends upon how you want to view the movie- as the director intended with its nominal audio track or make up sound fields using DSPs.

7.1 suggested speaker layouts from DTS: here & here

7.1 suggested speaker layouts from DD: here

Regards

[Paul Spencer]

5 channel makes sense on a budget, at some point it starts to get silly unless you have silly money to spend! I'd rather have 2 channel done right, than fubar 5 channel. Then again, I'd rather have 5 channel if done right.

[Bus_Boy]

So if you have a 6, or 7 channel reciever, but the audio playback is only in 5 channels, does the reciever send signal to the remaining speakers, or do they not play unless the movie supports the extra channels?

Vice versa, what happens if say a blue ray is formatted in 7.1, but only connected to a 5.1 receiver?

Craig, thank you for those links. Those setups are actually a little different from how i thought the rear speakers were typically placed. I always thought that the listener should be further from the fronts, closer to the rears. They have the listener centred between all speakers. Is this how other members also have their speakers placed?

Edited April 17, 2011 by Bus_Boy
brain fart

[Craigandkim]

BB,

ideally the listening position (LP) should be centrally located between the speakers- sometimes this is not possible- hence why there are the set-up functions containing speaker distances (this enables time delays to ensure correct arrival of audio to the LP from all speakers).

If you have a 7.1 soundtrack with only 5.1 system, once again this is taken care of in your set-up configuration, by programming your specific speaker config into your receiver. And yes the receiver can populate the extra channels by the use of the DSP functions. For example DD Pro-logic IIz- turning a 2 channel source into a 7 channel output. This all assuming you are sending a bitstream signal from transport to the receiver for processing and decoding.

In a nut shell, any speaker system set-up with more than 7 speakers is relying on the special effects (DSP's) of your receiver to create a sound field which does not exist on the disc.

Also remember that receivers touting a 7.2/9.4, etc set-up is just advertising it can cater for 2x or 4x sub outputs. There is only one mono LF channel. It is generally accepted that having more than one sub is beneficial with evening out the low frequency response within the room.

Edited April 17, 2011 by Craigandkim

[Frizzo]

I have looked into various 7.1 receivers and came to the conclusion that:

(a) it is marketing (the marketing of audio sound cards pushed me too far),

( not having any good ideas the marketing department came up with the concept of Zone 1 & Zone 2. So you can listen to music in other rooms. (one would think that buying another stereo would be the more obvious answer), and

© a 7.1 receiver can drive a 5+2.1 system, that is ... the L+R speakers are bi-amped in a 5.1 surround sound configuration. This is a good solution.

I have a bias for option ©.

[ArthurDent]

Also remember that receivers touting a 7.2/9.4, etc set-up is just advertising it can cater for 2x or 4x sub outputs. There is only one mono LF channel.

True but if also redirecting bass from other speakers to the subs some high end systems allow you to steer that bass to the appropriate sub(s).

[Craigandkim]

Which ones Ken?

PS. BB..I think that 5.1 will be quite adequate for most HT rooms, however I think that most low to mid-range receivers start with 7 channels of amplification these days, so as Frizzo said option © or set-up for a 7.1.

Edited April 17, 2011 by Craigandkim
ps

[ArthurDent]

Probably ones beyond my spending limits. Check out the "Ultra Hi-end HT gear ($20,000+)" thread on AVS as this subject comes up for discussion from time to time. Some of the custom installers, cineramax for one have some pretty cool computer systems that will redirect bass or anything else for that matter from and to anywhere you want it and to any number of subs. Luckily I'm fairly handy with a soldering iron so I've implemented my own modest system for redirecting front left and right main and left and right rears to the right subs.

Edited April 17, 2011 by KenTripp
Can't spell

[Bus_Boy]

It looks like i've got my work cut out for me as far as researching goes. I guess ultimately i would be happy with 5.1, but as mentioned above, it's the higher channel receivers that also offer greater power output. As i'm on a budget, i would prefer a receiver that can adequetely drive my speakers without the need to add on additional power amps, at least for the time being.

Terms like "DD Pro-logic IIz" i am not familiar with - in the case of receivers, do all receivers that are above 5.1 create the extra effects needed for the additional speakers, or is that strictly a higher end feature?

[Craigandkim]

BB,

yes, you have some research to do before spending your hard earned $$. Have you thought about 2nd hand or superseded models? Be open to interstate bargaining via the plethora of online reputable shops (Cairns being a fairly small market may not support the best bargains): ie-

http://clefhifi.com.au/catalog/index.php?cPath=21

http://www.carltonaudiovisual.com.au/?q=node/view/31

http://www.audiotrends.com.au/shop.php?category=41

http://www.sydneyhifimonavale.com.au/index.cfm/Products/Hi_Fi.html?groupid=8

http://www.eastwoodhifi.com.au/specials.htm

Try your local SNA retailers as well- you'll find that they are very accommodating.

Regarding effects...start researching the models at your price point in comparison to the higher priced model. Dont worry about the fancy effects terminology- as long as the receiver meets your basic needs (processing the main codecs, enough inputs, enough power and enough "future proofing" for your short -long term requirements) you'll be laughing.

Cheers

[RockandorRoll]

Most receivers are 7.1 now, it doesnt mean you have to use it. Most will let you assign the 2 extra channels as amplification for the fronts.

whats your budget and im sure you'll get some recomendations?

i only use 5 channels but my AVR is 7.1 it would be almost impossible to find a good quality AVR that isnt at least 7.1.

[Craigandkim]

Look whats here right now...no 3D but who gives a....

http://www.stereo.net.au/forums/showthread.php/34198-Yamaha-RX-V1800-7.1-Receiver

[markeroonie]

Have a look at the database reference the amount of 7.1 titles available hereDepends upon how you want to view the movie- as the director intended with its nominal audio track or make up sound fields using DSPs.

Interesting, I had a look at the list, and find it hard to believe that a lot of those releases were ever 7.1 in the first place, old movies, tv shows etc

Perhaps it's a little like adding colour to B+W movies, or adding 3D after filming has finished. It's possible, but why would you bother

[DoggieHowser]

I use a Denon AVR-4810 which has DSX and Dolby IIz processing which upmixes 5.1/7.1 up to 11.1 and 9.1 respectively.

I have set up all 11 speakers to see how they worked.

Even in a small room, I find the wides to work quite effectively for some action flicks, like in Transformers II. In the IMAX forest scene, when Megatron is circling the location looking for Sam, the wides provide a seamless pan around the viewer. Pretty nifty.

While cinemas typically only have a 5.1 source, they usually have far more speakers than just 5.1. In particular, there's a wall of speakers on the left and right of the theater that a typical 5.1 setup at home does not. The wides IMHO covers up that gap.

On the other hand, there are some shows where there is a slightly out of phase narrator's voice which gets f**ked up by the DSX processing. I think the phase variances get more pronounced by DSX creating what's known as the "voice of god effect". For such movies, I really have to turn off DSX wides. The only movie I have encountered this was Wolfman. But I did read in the AVS 4810 owner's thread that others have found the same issue in other shows.

For the heights, IMHO, the type of speakers play a big role. I'd avoid any dipole/omnipole/bipole speaker because it creates such a diffuse effect to make it undiscernable. FWIW, I also recommend regular speakers for new HD soundtracks with discrete channels. The days of using dipole/bipole stuff to create diffuse wider sound effects when we only had a matrixed rear channel is over.