Noah
Very perceptive as I have thought about just that. Put the center speaker NOT on stands and face it upward. However, there are lobs in the vertical plane and this could be an issue. But I could do a crossover that optimized the vertcal plane down at 15 degrees or so. I have to think some more, do some simulations and then try some things.
I just can't see why you need the small gain provided by the screen with the lumin power available with a modern projector. I tone down the light output of my projector and I use a dull bedsheet with negative gain, otherwise its too bright. I do have a very dark room, but it seems to me that there are options that would allow you to use the bedsheet (far far better than an "acoustically transparent (NOT!)" screen).
Very perceptive as I have thought about just that. Put the center speaker NOT on stands and face it upward. However, there are lobs in the vertical plane and this could be an issue. But I could do a crossover that optimized the vertcal plane down at 15 degrees or so. I have to think some more, do some simulations and then try some things.
I just can't see why you need the small gain provided by the screen with the lumin power available with a modern projector. I tone down the light output of my projector and I use a dull bedsheet with negative gain, otherwise its too bright. I do have a very dark room, but it seems to me that there are options that would allow you to use the bedsheet (far far better than an "acoustically transparent (NOT!)" screen).
center channel
As an idea for the center solution...
Does the vertical off axis response characteristics match the horizontal response characteristics? If so I would say tilt it back for the center to be at the specified 22.5deg tilt.relative to listening position.
If not, I would try it with the speaker laid horizontal and tilt upwards to the 22.5deg axis with listening position...
Tony
As an idea for the center solution...
Does the vertical off axis response characteristics match the horizontal response characteristics? If so I would say tilt it back for the center to be at the specified 22.5deg tilt.relative to listening position.
If not, I would try it with the speaker laid horizontal and tilt upwards to the 22.5deg axis with listening position...
Tony
re: center channel solution
I'm gonna go out on a limb and guess the lobing referred to is a result of the mixed responses from the waveguide and woofer if the speaker is tilted back.
A horizontal placement of a speaker with the woofer and horn side by side would result in grossly different response across the horizontal plane.
I'm gonna go out on a limb and guess the lobing referred to is a result of the mixed responses from the waveguide and woofer if the speaker is tilted back.
A horizontal placement of a speaker with the woofer and horn side by side would result in grossly different response across the horizontal plane.
Re: center channel
Tony
Again another cool idea - but I hadn't thought of that one!! No the response are quite differnt vertical and horzontal as you might imagine with a vertical displacement of the sources.
Thanks for that idea. I may actually try that one quite soon. Very good idea!!
TRADERXFAN said:
Tony
Again another cool idea - but I hadn't thought of that one!! No the response are quite differnt vertical and horzontal as you might imagine with a vertical displacement of the sources.
Thanks for that idea. I may actually try that one quite soon. Very good idea!!
Re: re: center channel solution
The lobing is a result of the non-coincident sources at the crossover.
The less than ideal vertical response then become the horizontal response when it placed on its side so what you say is also true.
I have thought that the center speaker might want be narrower in directivity than the sides, but it still needs to be of the same configuration etc. If it were narrower then the "hole" could be moved out of the passband.
Ed LaFontaine said:
The lobing is a result of the non-coincident sources at the crossover.
The less than ideal vertical response then become the horizontal response when it placed on its side so what you say is also true.
I have thought that the center speaker might want be narrower in directivity than the sides, but it still needs to be of the same configuration etc. If it were narrower then the "hole" could be moved out of the passband.
"Put the center speaker NOT on stands and face it upward."
The 9 deg I mentioned is with no tilt, but if it hadn't been enough I actually would have tilted it downward.
Tilting it upward enough might create an issue with ceiling reflection, vs a floor reflection nicely attenuated by carpet.
"I just can't see why you need the small gain provided by the screen with the lumin power available with a modern projector. "
I really wanted an acoustically transparent screen; my first was Dazian fabric, roughly unity gain.
It was just too dim.
Several points:
1) I forget which projector you have, but the typical "1000 L" projector nets a few hundred L after calibration for correct color.
2) The gain isn't small - 2.8 w/optimum setup; I estimate I'm getting about 1.8.
3) A 133" screen is about double the area of the typical 8-ft screen
3) Not exactly germaine, but the HP is retroreflective, which gives it several qualities I'm loathe to give up - uniform image brightness from any viewing angle, good rejection of off-axis ambient light, and relative immunity to waves.
The 9 deg I mentioned is with no tilt, but if it hadn't been enough I actually would have tilted it downward.
Tilting it upward enough might create an issue with ceiling reflection, vs a floor reflection nicely attenuated by carpet.
"I just can't see why you need the small gain provided by the screen with the lumin power available with a modern projector. "
I really wanted an acoustically transparent screen; my first was Dazian fabric, roughly unity gain.
It was just too dim.
Several points:
1) I forget which projector you have, but the typical "1000 L" projector nets a few hundred L after calibration for correct color.
2) The gain isn't small - 2.8 w/optimum setup; I estimate I'm getting about 1.8.
3) A 133" screen is about double the area of the typical 8-ft screen
3) Not exactly germaine, but the HP is retroreflective, which gives it several qualities I'm loathe to give up - uniform image brightness from any viewing angle, good rejection of off-axis ambient light, and relative immunity to waves.
How could you loose 80-90% of the light output just correcting the color. That just doesn't seem right. How close do you sit to this massive screen? I mean there are optimum sizes and distances etc. A screen that big would have you sitting back about 20 feet or more to be optimum and thats if its 1080. At 720 it would be even further.
Are your eyes OK?
Are your eyes OK?
"How could you loose 80-90% "
More like 70%; the way I learned it, "a couple" is roughly 2, "a few" is roughly 3, more than that is "several".
First, most mfgr's just lie about the rating, and the lumens they do achieve is with all controls set to give max brightness, which gives much too high a color temp, and poor grayscale tracking, and probably white clipping.
Also they spec brightness at minimum throw ratio; at the long end of the throw range where I'm at, brightness is typically 30% lower because of the smaller effective aperture.
You can check it out for yourself in the reviews at projectorcentral.com
And I forgot to mention that the UHP arc lamps used in projectors lose about half their brightness by half way through their lifetime.
I sit roughly in the middle of my 14 ft wide by 22 ft long room, which is slightly closer than the 1.2 (or is it 1.25) X screen width recommended for HD material.
More like 70%; the way I learned it, "a couple" is roughly 2, "a few" is roughly 3, more than that is "several".
First, most mfgr's just lie about the rating, and the lumens they do achieve is with all controls set to give max brightness, which gives much too high a color temp, and poor grayscale tracking, and probably white clipping.
Also they spec brightness at minimum throw ratio; at the long end of the throw range where I'm at, brightness is typically 30% lower because of the smaller effective aperture.
You can check it out for yourself in the reviews at projectorcentral.com
And I forgot to mention that the UHP arc lamps used in projectors lose about half their brightness by half way through their lifetime.
I sit roughly in the middle of my 14 ft wide by 22 ft long room, which is slightly closer than the 1.2 (or is it 1.25) X screen width recommended for HD material.
Re: Re: Kit Status?
When did Ai go out of business? I just received an email from them 2 - 3 weeks ago with their current price list. Now I understand that the Abbey and Nathan are different than the Ai ESP12 and ESP10 because you further developed them, but they should still be an option, correct? And the ESP15 is the same as the Summa if one decided to go that route, as you said previously. Sorry just wanting clarification about them in/out of business.
gedlee said:
When did Ai go out of business? I just received an email from them 2 - 3 weeks ago with their current price list. Now I understand that the Abbey and Nathan are different than the Ai ESP12 and ESP10 because you further developed them, but they should still be an option, correct? And the ESP15 is the same as the Summa if one decided to go that route, as you said previously. Sorry just wanting clarification about them in/out of business.
I guess that you don't understand a manufacturing business. The expenditures on setup, design and development, etc. are actually small compared to the huge expenditure required to buy the stock of parts that must be available to do a production run. You can't just buy ones and twos of things like DIYers do. You have to order 100's and 1000's of everything, all at one time, and this takes a large one time capital expenditure - a hurdle if you will - to get past before you can start to build up a supply of product to sell and generate cash flow. This is exactly where AI was when they could not get the cash to get past this hurddle. As you may know there is a financial crisis on and cash is a little tight right now.
To do product on a "made to order" basis pushes the expenses through the roof and the "production" prices are no longer viable.
To do product on a "made to order" basis pushes the expenses through the roof and the "production" prices are no longer viable.
I know enough not to get into it, nor would I recommend anyone jump too deep without some pre-planning and commitment from customers.
Normally when anyone starts a production facility, they will always have customers lined up due to prior relations in the business. If this did not happen, then it was poor planning.
Material cost is generally the one of the lesser part of cost of any product, even if you get materials is small quantity. However, if the production facility was setup without the capability to supply samples, then there is a big problem with the initial planning of the facility.
Normally when anyone starts a production facility, they will always have customers lined up due to prior relations in the business. If this did not happen, then it was poor planning.Material cost is generally the one of the lesser part of cost of any product, even if you get materials is small quantity. However, if the production facility was setup without the capability to supply samples, then there is a big problem with the initial planning of the facility.
Its awfuly easy to criticize a situation that you know nothing about.
My partner is one of the largest designers and installers of audio equipment in Thailand and SE Asia (EAD-AV.com). He IS a big customer. He had arrainged for loans when we started and had his own business to back up the loans and sell and distribute the product. When the economy went south so did his business as well as the loan availability. Plans are one thing, reality is another. No matter how well you plan Sh_t happens.
But the finance side of things were never my part of the project and yes he did make some mistakes. The technical side is complete. We could and did build samples and they are all over Bangkok. But you can't make any money on samples. You have to plan for the long haul. He still claims that he will revive Ai. I'll just have to wait and see.
My partner is one of the largest designers and installers of audio equipment in Thailand and SE Asia (EAD-AV.com). He IS a big customer. He had arrainged for loans when we started and had his own business to back up the loans and sell and distribute the product. When the economy went south so did his business as well as the loan availability. Plans are one thing, reality is another. No matter how well you plan Sh_t happens.
But the finance side of things were never my part of the project and yes he did make some mistakes. The technical side is complete. We could and did build samples and they are all over Bangkok. But you can't make any money on samples. You have to plan for the long haul. He still claims that he will revive Ai. I'll just have to wait and see.
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