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JapanDave dedicated theater build. - Page 19

post #541 of 574
12/29/12 at 11:03pm
Thread Starter 
For the time being , I am EQ'ing the system.

Here are a few before and after shots of the EQ'ed room.

My Center Speaker


The subs,
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post #542 of 574
1/24/13 at 2:20am
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Got some time to play with REW. These are the 4 subs at the front wall. Not max SPL, but I gave them a fair bit of power.





How do I interpret that waterfall graph? Is it OK or is that problem @ 25hz going to affect the SQ?
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post #543 of 574
1/24/13 at 3:18am
How have you set the crossover for them? specifically the frequency and slope?

I'd be more concerned about the bit that IMO really matters - 40 to 80hz.
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post #544 of 574
1/24/13 at 3:39am
Thread Starter 
Quote:
Originally Posted by Elill View Post

How have you set the crossover for them? specifically the frequency and slope?

I'd be more concerned about the bit that IMO really matters - 40 to 80hz.
At present I am experimenting with the mains HP filter @ 35hz.. They are +/- 2db @38Hz @ 123db at 1m. Then I am LP'ing the LFE channel @ 75hz. This sound the best so far that I have experimented with.

Did you have some concerns or thoughts?

Cheers
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post #545 of 574
1/24/13 at 1:14pm
Interesting - I'd want it flat though there, that may or may not be too much boost for your mains (that's my way of saying I'd flatten it out, but don't want to be responsible for damaging anything biggrin.gif )

Regarding the 25hz issue, with only thing that'd help that is treatments. I'm guessing its a function of your room construction. Typically you'd see a spike in the SPL where you have the decay, but in this instance you dont - well not much and I doubt eq will fix it
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post #546 of 574
1/24/13 at 2:16pm
Thread Starter 
Quote:
Originally Posted by Elill View Post

Interesting - I'd want it flat though there, that may or may not be too much boost for your mains (that's my way of saying I'd flatten it out, but don't want to be responsible for damaging anything biggrin.gif )

Regarding the 25hz issue, with only thing that'd help that is treatments. I'm guessing its a function of your room construction. Typically you'd see a spike in the SPL where you have the decay, but in this instance you dont - well not much and I doubt eq will fix it
I agree absolutely with you there. But remember this is before EQ and only the front 4 subs and is not maxed out. Once I add the 3 back subs to the equation it should smooth that part of the room out (This has been pre-measured and precisely the reason I am adding 3 more of these subs) I have no doubts in my mind that I will most likely have a flat response down to 2hz @ 105db at the main LP. I may even get higher SPL than that. But from 10hz - 80hz should be well over 120db giving me some headroom for EQ.

Thoughts?
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post #547 of 574
1/24/13 at 2:29pm
Quote:
Originally Posted by JapanDave View Post

Got some time to play with REW. These are the 4 subs at the front wall. Not max SPL, but I gave them a fair bit of power.





How do I interpret that waterfall graph? Is it OK or is that problem @ 25hz going to affect the SQ?

This is what me and another acoustics guys agreed on as a minimum targets for LF ringing:



The above is from our white paper, which although focused on two channel, is very relevant to home theater. The main change for multi-channel with subs and EQ use would be to tighten up the LF frequency response targets significantly. It goes into quite some detail on what measurements are relevant and what to look for with plenty of examples of REW graphs.

I would imagine that 25Hz is likely a length mode. If you integrate the back array properly you will be able to cancel it out. You will need ability to separately delay the rear array to the front and maybe invert polarity.
Edited by Nyal Mellor - 1/24/13 at 2:38pm
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post #548 of 574
1/24/13 at 2:40pm
Quote:
Originally Posted by zheka View Post

what about tactile effects at the ULF? One could probably feel 5Hz signal at levels below 110dB. no first hand experience here, just a guess.

Can't speak for ULFs but standing in the bass 'bin' (horn mouth) at a night club for 'testing' purposes is kind of interesting wink.gif
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post #549 of 574
1/24/13 at 2:57pm
Thread Starter 
Quote:
Originally Posted by Nyal Mellor View Post

This is what me and another acoustics guys agreed on as a minimum targets for LF ringing:

The above is from our white paper, which although focused on two channel, is very relevant to home theater. The main change for multi-channel with subs and EQ use would be to tighten up the LF frequency response targets significantly. It goes into quite some detail on what measurements are relevant and what to look for with plenty of examples of REW graphs.

I would imagine that 25Hz is likely a length mode. If you integrate the back array properly you will be able to cancel it out. You will need ability to separately delay the rear array to the front and maybe invert polarity.

Very interesting. I have not read thge white paper yet, but I wanted to address the ability to adjust delays etc.

I am lucky in that regard as my processor will allow me to adjust each individual sub drivers delays (7 of them) individually. So I have all the flexibility needed to do what you say. Now , seeming that I am the doing it, I am going to need a lot of guidance. What would inverting the polarity exactly do?
I am going to read that paper now.
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post #550 of 574
1/25/13 at 11:36am
Quote:
Originally Posted by JapanDave View Post

Very interesting. I have not read thge white paper yet, but I wanted to address the ability to adjust delays etc.

I am lucky in that regard as my processor will allow me to adjust each individual sub drivers delays (7 of them) individually. So I have all the flexibility needed to do what you say. Now , seeming that I am the doing it, I am going to need a lot of guidance. What would inverting the polarity exactly do?
I am going to read that paper now.

Controls like polarity, phase and delay are all kind of similar things when talking about subwoofers: basically you are playing with the phase integration of your subwoofers. By playing with phase you can start to 'cancel' room modes. See my subwoofer acoustics page for more, and in particular follow the link there to the Blu-Ray forums where there is some good info on room mode cancellation. You can also get into a quasi or full double bass array type setup.
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post #551 of 574
1/26/13 at 8:25pm
Thread Starter 
Quote:
Originally Posted by Nyal Mellor View Post

Controls like polarity, phase and delay are all kind of similar things when talking about subwoofers: basically you are playing with the phase integration of your subwoofers. By playing with phase you can start to 'cancel' room modes. See my subwoofer acoustics page for more, and in particular follow the link there to the Blu-Ray forums where there is some good info on room mode cancellation. You can also get into a quasi or full double bass array type setup.
Very interesting. That Bluray forum thread was very informative. smile.gif
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post #552 of 574
1/27/13 at 3:20pm
Perhaps I missed it, but what are you using for the EQ device?
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post #553 of 574
1/27/13 at 5:10pm
Quote:
Originally Posted by LeBon View Post

Perhaps I missed it, but what are you using for the EQ device?
Per Post 1, Datasat RS-20i.
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post #554 of 574
1/27/13 at 8:57pm
Thread Starter 
Quote:
Originally Posted by Roger Dressler View Post

Per Post 1, Datasat RS-20i.
Thanks Roger.
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post #555 of 574
2/12/13 at 7:52am
Been marveling over your incredible build! Subscribed and I would like to say how impressed I am with your gear choice and ingenuity. That swinging screen door solution is pure genius man! On the D-Cinema forum member Cineramax builds special client home cinemas for A-List Hollywood directors and the like and he raves about the Quested line of speakers. Glad to hear you solved your ear pressure issue. Lookin forward to hearing your impressions once you get all 7 18's goin. Great job man!
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post #556 of 574
2/12/13 at 3:37pm
Thread Starter 
Thanks for the kind words. Still not quite finished (Is it ever? LOL)

As for the subs, I should have the sound proof doors installed soon and I can install the drivers and start the EQ process again.

I have been trying to figure out a way to apply a house curve to sub 20hz frequencies and got lots of advise so far.

I probably should post more in this thread though.

Cheers Dave
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post #557 of 574
2/12/13 at 10:25pm
Quote:
Originally Posted by JapanDave View Post

Thanks for the kind words. Still not quite finished (Is it ever? LOL)

As for the subs, I should have the sound proof doors installed soon and I can install the drivers and start the EQ process again.

I have been trying to figure out a way to apply a house curve to sub 20hz frequencies and got lots of advise so far.

I probably should post more in this thread though.

Cheers Dave

Cool man. Pm or follow member MKtheater about help setting up a sub 20 house curve. He should be able to help. He is the king of setting up multiple sub house curves and he is all about ULF down to below 5hz.
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post #558 of 574
2/13/13 at 6:48am
Thread Starter 
I posted this in my sub thread , but I will post this here as well.
I have been playing with the LP and I moved it forward a tad and this is what I got. Safe to say I never imagined that moving the main listening position forward would change the in room response this much.
I purposefully bumped the area from 20hz and below, other wise it would be flat. The biggest win I found was that the waterfall plot .

All measurements done with Audix TM1 and sound devices USBPre 2 mic pre amp.



Before,



After,


Edited by JapanDave - 2/13/13 at 7:23am
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post #559 of 574
3/12/13 at 11:00pm
Any updates?
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post #560 of 574
3/13/13 at 2:27am
Thread Starter 
Quote:
Originally Posted by Reddig View Post

Any updates?

Nothing yet. I have cleaned out the back rrom ready for the second IB sub install. Roger is coming around tomorrow, so hopefully he likes it, but being that it is unfinished I guess I have an excuse.
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post #561 of 574
3/13/13 at 5:59pm
Quote:
Originally Posted by JapanDave View Post

Nothing yet. I have cleaned out the back rrom ready for the second IB sub install. Roger is coming around tomorrow, so hopefully he likes it, but being that it is unfinished I guess I have an excuse.

Cool sometimes getting the cleaning work done can be half the battle. Wish you good luck my man!
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post #562 of 574
3/26/13 at 2:10am
Quote:
Originally Posted by JapanDave View Post

Nothing yet. I have cleaned out the back room ready for the second IB sub install. Roger is coming around tomorrow, so hopefully he likes it, but being that it is unfinished I guess I have an excuse.
Roger was there, and he liked it. Putting it mildly.

When we first fired up the system, I asked to play an old Dolby test disc "Explore Our World" just to get a reference for the setup. First it has the normal bandlimited noise stepped thru the 5 main channels. Then it has a filtered bass signal stepped thru 6 channels (adding the LFE). This one sniffs out bass management settings in 10 seconds, and indeed we found some issues with the setup. Rather than try to diagnose what happened with the custom setup, Dave switched to the processor's native setup, and all worked normally.

There was still a 3 dB discrepancy in the surround levels, and I initially thought that was the RS-20's theatrical heritage coming thru (cinema surrounds are calibrated 3 dB lower), but later that day we visited the setup menu again and it said it was in the "standard 7.1" mode. But the system has 5.1 speakers, so I wonder if the processor was splitting the surrounds at -3dB. Dave will find out when he changes it to a 5.1 speaker setup. Anyway, we calibrated it so it did not affect our listening.

The change in speaker bass management also resulted in somewhat overexuberant bass, so Dave pulled up his "Synthesis" target curve and I think we both immediately felt that was right on the money balance-wise.

Dave let me first play a CD I burned with several familiar music selections, and was happy to see we agree that louder is not always better. Playing at comfortable loudness, I was nonetheless immediately struck by the quality of the bass. Every note was heard as a separate event. No blurr or overhang, every note spoke with defined pitch, attack and integrated beautifully with the rest of the spectrum. The delicacy was a pleasant surprise, but whenever it called for either subterranean depth (the HVAC motors that were picked up in the Dido recording), or just a full measure of dynamics in Lyle Lovett, it was all there in full measure as easy as you please. No sweat, no strain.

Time for some movies. The famous WOTW "crawl out of the street" scene shook me in the seat, which was remarkable given the seats sit on a carpeted concrete floor that is not vibrating. This was when playing at -15 dB.

The "going down" crash scene in "Flight of the Phoenix" put me right inside that rickety aircraft. It was a jawdropping visceral experience. Just astoundingly good.

Now all this blubbering about the bass may lead you to think the rest of the sound was pretty normal. But no. The L/C/Rs are Quested HQ210, and whatever may have been bothering Dave about the high frequencies of other speakers he's had was not in evidence with these. Detail galore right through the woven screen, smooth clean sound one can enjoy for hours without fatigue. The surrounds were just as impressive. I forget the details, but they seemed to be 5' tall line arrays with ribbon tweeters. There may be a second pair in the future, I believe.

Watching Star Trek, which also sounded great, I felt the video image was tending to crush into the black, so we dug out the Spears and Munsil disc and did some quick fiddling with the Oppo controls just to see what would happen -- so as to not mess the PJ's settings. Raising the brightness and reducing the contrast helped a lot, but I suspect there's a better way to refine the calibration of the laser-powered image than that. More importantly, the curved screen fills what I estimate is a full 60-deg viewing angle when showing 2.40 content (it's a CIH setup), which creates its own sense of involvement that complements the likewise involving sound.

How much of this astonishing total system performance can be attributed to any one thing? I think it is the superb blend of all the factors that makes this theater and the experiences it provides so special. The processor, amps, main speakers, subs, room design and construction, acoustic treatments, tuning/target curve, every element is there in full measure. As Salieri said: "Displace one note and there would be diminishment..."

Congratulations, Dave, on the amazing project. And my heartfelt thanks for your gracious hospitality in opening your home to a total stranger.
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post #563 of 574
3/26/13 at 9:14am
Quote:
Originally Posted by Roger Dressler View Post

Roger was there, and he liked it. Putting it mildly.

When we first fired up the system, I asked to play an old Dolby test disc "Explore Our World" just to get a reference for the setup. First it has the normal bandlimited noise stepped thru the 5 main channels. Then it has a filtered bass signal stepped thru 6 channels (adding the LFE). This one sniffs out bass management settings in 10 seconds, and indeed we found some issues with the setup. Rather than try to diagnose what happened with the custom setup, Dave switched to the processor's native setup, and all worked normally.

There was still a 3 dB discrepancy in the surround levels, and I initially thought that was the RS-20's theatrical heritage coming thru (cinema surrounds are calibrated 3 dB lower), but later that day we visited the setup menu again and it said it was in the "standard 7.1" mode. But the system has 5.1 speakers, so I wonder if the processor was splitting the surrounds at -3dB. Dave will find out when he changes it to a 5.1 speaker setup. Anyway, we calibrated it so it did not affect our listening.

The change in speaker bass management also resulted in somewhat overexuberant bass, so Dave pulled up his "Synthesis" target curve and I think we both immediately felt that was right on the money balance-wise.

Dave let me first play a CD I burned with several familiar music selections, and was happy to see we agree that louder is not always better. Playing at comfortable loudness, I was nonetheless immediately struck by the quality of the bass. Every note was heard as a separate event. No blurr or overhang, every note spoke with defined pitch, attack and integrated beautifully with the rest of the spectrum. The delicacy was a pleasant surprise, but whenever it called for either subterranean depth (the HVAC motors that were picked up in the Dido recording), or just a full measure of dynamics in Lyle Lovett, it was all there in full measure as easy as you please. No sweat, no strain.

Time for some movies. The famous WOTW "crawl out of the street" scene shook me in the seat, which was remarkable given the seats sit on a carpeted concrete floor that is not vibrating. This was when playing at -15 dB.

The "going down" crash scene in "Flight of the Phoenix" put me right inside that rickety aircraft. It was a jawdropping visceral experience. Just astoundingly good.

Now all this blubbering about the bass may lead you to think the rest of the sound was pretty normal. But no. The L/C/Rs are Quested HQ210, and whatever may have been bothering Dave about the high frequencies of other speakers he's had was not in evidence with these. Detail galore right through the woven screen, smooth clean sound one can enjoy for hours without fatigue. The surrounds were just as impressive. I forget the details, but they seemed to be 5' tall line arrays with ribbon tweeters. There may be a second pair in the future, I believe.

Watching Star Trek, which also sounded great, I felt the video image was tending to crush into the black, so we dug out the Spears and Munsil disc and did some quick fiddling with the Oppo controls just to see what would happen -- so as to not mess the PJ's settings. Raising the brightness and reducing the contrast helped a lot, but I suspect there's a better way to refine the calibration of the laser-powered image than that. More importantly, the curved screen fills what I estimate is a full 60-deg viewing angle when showing 2.40 content (it's a CIH setup), which creates its own sense of involvement that complements the likewise involving sound.

How much of this astonishing total system performance can be attributed to any one thing? I think it is the superb blend of all the factors that makes this theater and the experiences it provides so special. The processor, amps, main speakers, subs, room design and construction, acoustic treatments, tuning/target curve, every element is there in full measure. As Salieri said: "Displace one note and there would be diminishment..."

Congratulations, Dave, on the amazing project. And my heartfelt thanks for your gracious hospitality in opening your home to a total stranger.

Sounds like a very fun time! Nice little right up. I've heard great things about the Quested LCRs.
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post #564 of 574
3/28/13 at 6:14pm
Thread Starter 
Well, I just have say thanks to Roger for the great day. It was awesome having you here Roger, I never thought I would ever be able to share this theater with anyone.

I also want to thank you for helping me with the setup of both the sound system and the projector, you have opened my eyes to a whole new world of tweaking. BTW, I checked the surrounds and you were right, the 7.1 made them 3db softer. So I had to reduce them a fe db after you left. I listened to that CD you gave a few times now and I can really appreciate what you are saying about the clarity. Who would have thought, a HT that is good for music as well. LOL!

Once I have the last 4 x 18" drivers installed and calibrated I am sure that I can improve on this system right now.

Anyway, that is all for now, I will post updates once I start the second IB sub.

Cheers
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post #565 of 574
3/29/13 at 2:13pm
Thread Starter 
I forgot to mention Dennis. In the room that I have he did a fantastic job of getting tamed for music and movies. Without his help I would have never been able to get a HT like this. Thanks Dennis.
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post #566 of 574
3/29/13 at 2:29pm
smile.gif
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post #567 of 574
3/30/13 at 4:37pm
Hi Dave.

Is your projector still the Vango? I think we bought our projectors at about the same time but I'm thinking I've got a few more hours on mine. smile.gif

John.
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post #568 of 574
4/1/13 at 4:44am
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Quote:
Originally Posted by dormie1360 View Post

Hi Dave.

Is your projector still the Vango? I think we bought our projectors at about the same time but I'm thinking I've got a few more hours on mine. smile.gif

John.

Yeah you are correct, you got yours just before me. I still have the Vango and it throws a great picture for sure.

How is your doing?
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post #569 of 574
4/1/13 at 11:05am
Quote:
Originally Posted by JapanDave View Post

Yeah you are correct, you got yours just before me. I still have the Vango and it throws a great picture for sure.

How is your doing?

Great....no problems, picture is the same as when I turned it on for the first time.
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post #570 of 574
4/30/13 at 2:34am
Any progress on second IB build?
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