q sound 3d and panels

q sound is a very impressive way to make 3d sound effects...

Roger waters "amused to death" is a nice album with great 3d effects.

With my Puritys I have a very wide 3 dimensional sound stage (in vocals and classic listening).

I was trying the Roger Waters cd and the 3d effects where absent.

I am wondering if this has something to do with panels and the rear wave.

I would appreciate any info/experience.

thanks
Nikos

I was listening to it just last Friday on my CLS based system and it's absolutely uncanny how well it was rendered. Many of the sounds were coming from far outside the room boundries to the left and right, with others coming from above and even well behind me. Mind you this is a 2 channel only system. The one line where Roger is singing about the "new Ferrarri car" and the car goes screaming by from right to left at high speed is absolutely awesome. My dog and I both jumped.

Short answer - absolutely no reason why this CD shouldn't be rendered to full effect with ML panels.

And to any of you who don't have this CD - go buy it. Possibly the best 2 channel demo CD ever made.

Hi MiTT, thank you for your answer.

could you pleeease describe from where do you hear the barking dog at the very beginning of "The Ballad of Bill Hubbard"?

thank you for your time.

Hi Nikos, this sounds like a possible speaker placement / room acoustics issue. Although having reversed phase on one of the speakers might also explain the collapsed soundstage.

To get the 3d effect, qSound is cross-mixing L/R signals with some added delay. This is exactly what happens naturally in a ML setup.

Big dipoles, offset a few feet from a rear/side wall have plenty of L/R cross-mixed sound arriving at the listener delayed by a few ms. (the rear wave will be X ms longer in arriving at your ears if undamped.

X = number of feet between the REAR of your panels, traveling to the front wall, bouncing off of it, traveling to the side walls, bouncing off of them at the same distance as the front panels (usually 6 to 8 ms). There is also sound reflected back between the two front speakers as well, and it will have a slightly shorter delay (4 to 7ms).

I’ll theorize that the combination of the natural cross-mixing from your speakers is cancelling the effect of the additional cross-mixing QSound intended to add.

Remember, a lot of ‘soundfields’ are engineered and tested with monopole, point source speakers.
Our big dipole, line-source speakers behave radically different, so that needs to be considered.

The fact that Tim’s system resolves this correctly shows that positioning and room variances will have a huge impact.

How far are your speakers from the Front/side walls and how toed-in are they?

Pics would help.

Nikos said:

Hi MiTT, thank you for your answer.

could you pleeease describe from where do you hear the barking dog at the very beginning of "The Ballad of Bill Hubbard"?

thank you for your time.

Click to expand...

It sounds like it's just behind my right shoulder and about 30-40 feet away.

JonFO thanks a lot. I think your are right. must be a cancellation because of room acoustics.

here is a bad pic. distance between panel and rear wall is 3feet for the right and 2.5 for the left (there are bookshelves behind the left panel). I don't have the sub you see in the pic.

MiTT said:

It sounds like it's just behind my right shoulder and about 30-40 feet away.

Click to expand...

that's the correct "position" of the dog!
great, now I know it can be done with panels...
thanks

MiTT said:

And to any of you who don't have this CD - go buy it. Possibly the best 2 channel demo CD ever made.

Click to expand...

Does it have just sound effects or is there any music on it ?

that's anothe attemp with different room positioning...

MiTT said:

I was listening to it just last Friday on my CLS based system and it's absolutely uncanny how well it was rendered. Many of the sounds were coming from far outside the room boundries to the left and right, with others coming from above and even well behind me. Mind you this is a 2 channel only system. The one line where Roger is singing about the "new Ferrarri car" and the car goes screaming by from right to left at high speed is absolutely awesome. My dog and I both jumped.

Short answer - absolutely no reason why this CD shouldn't be rendered to full effect with ML panels.

And to any of you who don't have this CD - go buy it. Possibly the best 2 channel demo CD ever made.

Click to expand...

I love this recording myself. I mentioned it on a different thread sometime ago and caught some negative flack for it. Seems many of the folk thought it was just noise.

At my last house with a dedicated listening room the 3d was astounding. At my present location with window and wall issues I have trouble realizing all this recordings potential. I get close but not quite there.

I must once again highly recommend this recording to anyone. If for only the 3d qualities. If you get this recording right your whole system will sound better as a result of your efforts. I know it worked that way for me. The music is pretty cool also, if you like Roger Waters.

Two other decent sounding Q-sound recordings I own are: Sting - Soul Cages the soundtrack to Robin Hood Prince of Thieves

Doug - out
PS My system has undergone a major upgrade and I will be posting updated pics soon.

JonFo said:

Hi Nikos, this sounds like a possible speaker placement / room acoustics issue. Although having reversed phase on one of the speakers might also explain the collapsed soundstage.

Click to expand...

how can I check the correct phase?
(I have Purity they are active. Is the power cable positioning (phase?) makes any difference?)

The music / lyrics are a bit moross but otherwise, assuming you like Roger Waters and PF, an absolute must for your collection.

As others have stated, there are numerous 3D effects. One not mentionned yet is the sound of the horse drawn buggy. It starts on the left side, comes forward and crosses left to right, and goes back and disappears in the far right corner of the soundstage. The sound of the horses hooves are quite something. From my listening chair, when it reaches the middle of the "crossover", the image is about four feet above and two feet in front of my ears.

And yes the dog barks in the beginning. If the system is set up correctly, should hear the barks about five feet to the right, five feet behind, and five feet or so above your right ear. This will depend on your specific setup.

As someone else stated, it really is a good disc to check out your system's clarity and imaging prowress.

And to answer someone elses question, it's not an "effects" CD. The "Q" sound aspect is used somewhat sparingly and to varying degrees, but adds to the incredible acoustic space rendered on this disc.

GG

Bernard said:

Does it have just sound effects or is there any music on it ?

Click to expand...

Actually I really like the music on it. I'd say that if you like Pink Floyd's "The Wall", then you're going to like this disc just about as well or possibly better.

It IS very much Roger Waters at his most sardonic, but overall I think it's a bit more optimistic than "The Wall" although every bit as bitting, it's just that instead of reminding us of how we're all F^*ked up he's speaking more to how F^*ked up the War Machine and ensuing Imperialism is. "Yellow Rose" is a very catchy, upbeat tune until you realize that he's singing about a lover killed in Tienemen Square. Hmmm, maybe not so upbeat after all.

There is another song where he is talking with a genie about granting him 3 wishes, and the voice of the genie is rendered with some awesomely deep bass that might make you jump the first few times you hear it, and checking your foundation for damage thereafter.

He goes on to sing about Andrew Lloyd Weber's awful stuff lingering for years and years, "but then an earthquake strikes the theater, the piano lid comes crashing down, and breaks his F^*king fingers" in "It's a Miracle" - so that's kind of fun.

You have to be in the right frame of mind, but yeah, I really like it.

Nikos said:

JonFO thanks a lot. I think your are right. must be a cancellation because of room acoustics.

here is a bad pic. distance between panel and rear wall is 3feet for the right and 2.5 for the left (there are bookshelves behind the left panel). I don't have the sub you see in the pic.

Click to expand...

Hi Nikos,

Thanks, the pic helps a lot.

Looking at the setup flanking the fireplace, I'd say that one possibility for the soundstage not being cohesive is that the reflection coefficients behind each speaker are different enough that it can impact the balance.

The bookshelf, with the various angles and depth, is definitely causing diffusion to happen on the left channel.
Also, the asymmetry in distances to left and right walls will project a skewed soundstage.

Further, the room is small, with lots of hard surfaces, so you probably have some modal ringing in the midrange and highs that further blurs the resolution of the system.

To confirm this, here’s an experiment to try:
Place two broadband absorbers (Fabric covered couch/sofa cushions will for testing) behind the two speakers, ensuring that the panels rear wave is fully covered vertically.

Then play the disc again and see what that does to the soundstage.

You might also need to threat the wall opposite the speakers with some absorption as well.

I will go out and get this today if I can find it ! Ill report back !

I won this yesterday on ebay for $1.99 with $2.95 S & H. Can't wait to :music:

CD available at CD Universe website.

GG

small improvement using cushions following JonFo sugestions..

BIG improvement placing speakers in a NEW position!!!!



as you can see now my speakers are taking my place in the couch and they are watching TV....

it's not funny, is the only place where speakers are working with q sounds effects.

It is important to have some distance between the edge of the speaker and the side walls as well as distance from your listening chair to the back wall to be able to clearly hear the Q sound effects. The former is more critical than the latter. I would also assume that the panel needs to be minimum of 4' and preferably 5' from the panel to the front wall (wall in back of your speaker).

In my room, I have 7' from the speaker to the sidewall and 10' from my listening chair to the back wall. My panels are 5' from the front wall.

Q sound effects are quite real and very audible.

GG