Build Log - First Home Theatre - Page 3

slobber · 23rd July 2012, 1:45 PM

Quote:

Originally Posted by Gonadman2

The bit that I'm stuck with at the moment is what colour to go with? The charcoal looks good, but most of the front end is charcoal, and I think this would have a nice effect with the light cascading down from under it. On the other hand, the teal breaks up the charcoal nicely, and is still easy on the eye. I fired up the projector to see if the teal is distracting but was pleasantly surprised to find that it was not at all.

Inspiring work Gonadman

I think you really need to use teal as all black = no definition of the shapes/curves you have made

Red Spade · 24th July 2012, 10:24 AM

When you bring any treatment into the room, you want to consider the total effect. The problem with carpet and curtains is that they are thin and only work at the very top end, and that gives you unbalanced absorption, so use those sparingly. Ideally what you want is absorption that has a broad range of effectiveness. A panel that is 50mm thick will do that.

This post shows that effect:
http://redspade-audio.blogspot.com.a...verb-time.html
with respect to reverb time

To give you an idea:

Those are 3 rooms. The one on the bottom is one version of my room with a Synergy horn prototype. You notice two things. Firstly, the reverb is lower so the room is slightly dead. Secondly, the reverb is quite uniform - notice how the top end doesn't droop much? That is due to the constant directivity of the speakers and that I've avoided thin treatments. The other two rooms have little to no treatment, I describe them more on the blog.

hlokk · 24th July 2012, 10:48 AM

In the lower one (yellow), what effect does the peak at 600hz result in? Odd that it has a spike while the other two don't.

Red Spade · 24th July 2012, 12:01 PM

I'm not entirely sure about the cause of the 600 Hz peak. That it occurs only in the time domain suggests ringing, and that points me to a rattly heater that I removed.

Comma · 24th July 2012, 3:21 PM

Quote:

Originally Posted by Red Spade

I'm not entirely sure about the cause of the 600 Hz peak. That it occurs only in the time domain suggests ringing, and that points me to a rattly heater that I removed.

Perhaps resonant frequency of something in the room (Materials/Objects)

seb · 25th July 2012, 10:04 AM

Don't you mean the peak occurred only in the frequency domain - that was graph of level vs frequency after all. It would be a real problem in the time domain - in the frequency domain one can remove the heater (if that was it) or use EQ. EQ won't fix a time domain problem.

Red Spade · 25th July 2012, 10:29 AM

seb,

That chart is showing time on the y axis - reverb time. In frequency response there was no peak like that. Let's not focus too much on this one. I can't repeat that measurement and find out what was causing the peak. I suspect when I measure the system again it won't be there.

seb · 25th July 2012, 11:23 AM

Red, no worries. of course, my bad, it is not a level vs freq graph. However, the graph does not show the evolution of any parameter with respect to time - it shows single index values of "decay time" vs freq but it doesn't tell me anything about how the sound level varies over time (is it a straight line decay, double slope, etc). We may have to agree to disagree on what "time domain" means in this context.

Gonadman2 · 30th July 2012, 12:25 AM

Update time.

Today was quite productive, with a few little jobs having been completed over the past few weeks I was able to get the bigger ones sorted.

When I stapled the material to the front panel of the sub enclosures, I foolishly fired the staples into the top side of the panel for ease. Unfortunately this edge needs to be glued to the top panel, and gluing to fabric was never going to result in a quality seal.

This meant pulling all of the staples and re-attaching to the front side of the panel. Lots more staples, and a better quality job.

I finished routing the cables through the enclosures as well, and soldered the LED Strip lighting controller in before the top panel is glued. The foam bricks soak up a little bit of volume in the enclosure as its a little on the large side. I will do some testing with and without, but thought I'd start with the higher Q enclosure to begin with.

The leading edge trim had been bothering me as to how I was going to complete it. During a routine trip to bunnings I found some Tasmanian oak that was 30mm x 8mm with bevelled corners. I finally had a solution. Next was how to cover it. In the end the mrs and I decided that a nice black stain would look best so that's what I did.

Mmmm, staining.

Close up of the finish in direct sunlight. I don't mind that you can see the grain and colour of the timber underneath, gives it a bit of an organic feel.

All mounted up and looking really tidy.

With that out of the way, it was time to start knocking up the screen. My good mate and fellow forum member Maccar86 is seen here banging a few brads in.

With the framing out of the way, it was a simple matter of stretching the Moleskin Matte Silver spandex across the frame. I settled on a White over Silver screen due to complete lighting control of the room and the superior image it delivers when doing so. We ran out of time today to complete the white, so here it is with just the Silver. Still reflects back a quality image. Also note the new LED Strip light, this is the first time I've had a chance to play with these things and I have found they are amazingly bright. I will be tidying up the trim on the lower right, it seems to have settled badly and shows in the LED light.

Hope you guys enjoy the update.

brayway · 30th July 2012, 5:39 AM

Looks awesome

Soo jealous

Pugs · 30th July 2012, 4:55 PM

sploosh....

now jus to convince the wife on having a basement HT..

PapaRubbery · 30th July 2012, 5:27 PM

Absolutely stunning, mate!

Any chance, when it's all done and dusted for a cost break down?

Would love to have this in a future home!

slobber · 30th July 2012, 5:32 PM

Quote:

Originally Posted by Pugs

sploosh....

now to convince the wife to dig out a basement HT..

Good luck with that

I wonder how much LFE will be transmitted to/thru the back wall ??

Pugs · 30th July 2012, 10:01 PM

Quote:

Originally Posted by slobber

Good luck with that

I wonder how much LFE will be transmitted to/thru the back wall ??

Will most likelt building so depending on the block it could be a very good idea

Sledge · 31st July 2012, 6:02 PM

I just wish i had a suitable room for something like this...

24th July 2012, 10:24 AM	#32
Red Spade Member Join Date: Feb 2010 Location: Melbourne Posts: 74	When you bring any treatment into the room, you want to consider the total effect. The problem with carpet and curtains is that they are thin and only work at the very top end, and that gives you unbalanced absorption, so use those sparingly. Ideally what you want is absorption that has a broad range of effectiveness. A panel that is 50mm thick will do that. This post shows that effect: http://redspade-audio.blogspot.com.a...verb-time.html with respect to reverb time To give you an idea: Those are 3 rooms. The one on the bottom is one version of my room with a Synergy horn prototype. You notice two things. Firstly, the reverb is lower so the room is slightly dead. Secondly, the reverb is quite uniform - notice how the top end doesn't droop much? That is due to the constant directivity of the speakers and that I've avoided thin treatments. The other two rooms have little to no treatment, I describe them more on the blog. __________________ Audio blog .::. DIY projects, articles and resources .::. Writer for Hifi Zine: http://www.hifizine.com/ DSP active point source horns + T20 sub horns under the floor + 8" waveguide surrounds + Custom Acoustic treatment

24th July 2012, 10:48 AM	#33
hlokk Member Join Date: Jul 2003 Location: WA Posts: 3,951	In the lower one (yellow), what effect does the peak at 600hz result in? Odd that it has a spike while the other two don't. __________________ Oh, for the love of science!

24th July 2012, 12:01 PM	#34
Red Spade Member Join Date: Feb 2010 Location: Melbourne Posts: 74	I'm not entirely sure about the cause of the 600 Hz peak. That it occurs only in the time domain suggests ringing, and that points me to a rattly heater that I removed. __________________ Audio blog .::. DIY projects, articles and resources .::. Writer for Hifi Zine: http://www.hifizine.com/ DSP active point source horns + T20 sub horns under the floor + 8" waveguide surrounds + Custom Acoustic treatment

25th July 2012, 10:29 AM	#37
Red Spade Member Join Date: Feb 2010 Location: Melbourne Posts: 74	seb, That chart is showing time on the y axis - reverb time. In frequency response there was no peak like that. Let's not focus too much on this one. I can't repeat that measurement and find out what was causing the peak. I suspect when I measure the system again it won't be there. __________________ Audio blog .::. DIY projects, articles and resources .::. Writer for Hifi Zine: http://www.hifizine.com/ DSP active point source horns + T20 sub horns under the floor + 8" waveguide surrounds + Custom Acoustic treatment

30th July 2012, 4:55 PM	#41
Pugs Member Join Date: Jan 2008 Location: St Marys, SA Posts: 7,869	sploosh.... now jus to convince the wife on having a basement HT.. __________________ PC Gamer, PC/ Networking Geek, Licenced Cabler, Sci Fi Junkie Jesus was a Chippie, I'm a data cabler..make sense ??? "I don't just have tickets on myself, I have a whole booklet of tickets on myself" My Becoming a Cabler & Tool Thread To The Cloud...!! Last edited by Pugs; 30th July 2012 at 5:07 PM.

25th July 2012, 10:04 AM	#36
seb Member Join Date: Jun 2001 Posts: 1,680	Don't you mean the peak occurred only in the frequency domain - that was graph of level vs frequency after all. It would be a real problem in the time domain - in the frequency domain one can remove the heater (if that was it) or use EQ. EQ won't fix a time domain problem.

25th July 2012, 11:23 AM	#38
seb Member Join Date: Jun 2001 Posts: 1,680	Red, no worries. of course, my bad, it is not a level vs freq graph. However, the graph does not show the evolution of any parameter with respect to time - it shows single index values of "decay time" vs freq but it doesn't tell me anything about how the sound level varies over time (is it a straight line decay, double slope, etc). We may have to agree to disagree on what "time domain" means in this context.

30th July 2012, 12:25 AM	#39
Gonadman2 Member Join Date: May 2006 Location: Perth Posts: 850	Update time. Today was quite productive, with a few little jobs having been completed over the past few weeks I was able to get the bigger ones sorted. When I stapled the material to the front panel of the sub enclosures, I foolishly fired the staples into the top side of the panel for ease. Unfortunately this edge needs to be glued to the top panel, and gluing to fabric was never going to result in a quality seal. This meant pulling all of the staples and re-attaching to the front side of the panel. Lots more staples, and a better quality job. I finished routing the cables through the enclosures as well, and soldered the LED Strip lighting controller in before the top panel is glued. The foam bricks soak up a little bit of volume in the enclosure as its a little on the large side. I will do some testing with and without, but thought I'd start with the higher Q enclosure to begin with. The leading edge trim had been bothering me as to how I was going to complete it. During a routine trip to bunnings I found some Tasmanian oak that was 30mm x 8mm with bevelled corners. I finally had a solution. Next was how to cover it. In the end the mrs and I decided that a nice black stain would look best so that's what I did. Mmmm, staining. Close up of the finish in direct sunlight. I don't mind that you can see the grain and colour of the timber underneath, gives it a bit of an organic feel. All mounted up and looking really tidy. With that out of the way, it was time to start knocking up the screen. My good mate and fellow forum member Maccar86 is seen here banging a few brads in. With the framing out of the way, it was a simple matter of stretching the Moleskin Matte Silver spandex across the frame. I settled on a White over Silver screen due to complete lighting control of the room and the superior image it delivers when doing so. We ran out of time today to complete the white, so here it is with just the Silver. Still reflects back a quality image. Also note the new LED Strip light, this is the first time I've had a chance to play with these things and I have found they are amazingly bright. I will be tidying up the trim on the lower right, it seems to have settled badly and shows in the LED light. Hope you guys enjoy the update.

30th July 2012, 5:27 PM	#42
PapaRubbery Member Join Date: Jun 2009 Location: Melbourne, Australia Posts: 1,204	Absolutely stunning, mate! Any chance, when it's all done and dusted for a cost break down? Would love to have this in a future home! __________________ www.circleofzinn.com ~This post constitutes medical advice~

31st July 2012, 6:02 PM	#45
Sledge Member Join Date: Aug 2002 Location: Adelaide Posts: 3,115	I just wish i had a suitable room for something like this... __________________ http://sledge1.mybrute.com OCAU Clan