Very true
. Merry Christmas to all of you to! Time does fly, another year is about to end.
My repair ended up being epoxy and fiberglass matt. Epoxy was chosen because it doesn't schrink when curing.
I did cut the speakers up into 25 pieces though
I think I would have been inconsolable if that happened to me lol. That’s an incredible amount of labour , only to have that outcome.
I had planned on having 2” thick walls ,and the biggest enclosure only a few feet high . Much wider also, so I don’t know if that would help .
Seeing other people’s issues kind of scares me off this idea a bit though, plus I would certainly have a lot of waste.
I had planned on using 1” mdf ,as I like the density
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Ahhh, I see. Not just up-scaling but also gamma and color space. I'll be interested to know what you think of the new TV's built in scaler vs the fancy video card.
Back in my early video projection days we had scan doublers. Basically making a 480P or 525P signal out of standard def interlaced. Some of them worked very well indeed. Then came the scalers, that would allow whatever output resolution you wanted. Things have come a very long way since then. All those many millions of HD and now UHD TV with built in scalers have really pushed the quality up and the price down.
I know what you mean about the TV being too small for the sound. Back when we bought our first flat screen TV I had my big OB+horn speakers either side of the screen. The sound was sooooooo big, full and clear that the little screen just seemed silly.
Back in my early video projection days we had scan doublers. Basically making a 480P or 525P signal out of standard def interlaced. Some of them worked very well indeed. Then came the scalers, that would allow whatever output resolution you wanted. Things have come a very long way since then. All those many millions of HD and now UHD TV with built in scalers have really pushed the quality up and the price down.
I know what you mean about the TV being too small for the sound. Back when we bought our first flat screen TV I had my big OB+horn speakers either side of the screen. The sound was sooooooo big, full and clear that the little screen just seemed silly.
Wesayso, how about a projector? It's even way WAF friendlier than a big black screen on the wall. When not in use, you only have that small box near the ceiling.
Having gone to projectors in the last 10 years, I can't go back to a tv anymore. I love my 120"+ screen!
And a lot of good projectors are cheaper than TVs these days.
Having gone to projectors in the last 10 years, I can't go back to a tv anymore. I love my 120"+ screen!
And a lot of good projectors are cheaper than TVs these days.
I see even 4K projectors are affordable these days....
It has always been my intention to one day have a projector, ever since the 90's where I used to bring a projector home from work for watching concert videos. I was delegated the role to setup video at conferences and allowed to take that projector home for the weekend. That projector was more than 3 times the price of my car (Opel GT at that time). I have suggested it to my girl a few times. I don't think she took me seriously.
It has always been my intention to one day have a projector, ever since the 90's where I used to bring a projector home from work for watching concert videos. I was delegated the role to setup video at conferences and allowed to take that projector home for the weekend. That projector was more than 3 times the price of my car (Opel GT at that time). I have suggested it to my girl a few times. I don't think she took me seriously.
DIY guy like you would have no trouble hiding the projector and screen in the ceiling.
Touch a button and they drop down!
If you don't want to bother with a screen, they sell pigmented paint, and you'd just need to paint the wall it is projected on.
Light bulbs in projectors also have come a long way. There's some with 5,000 to even 10,000 hours of life.
I love watching movies, but it will take a long time to fill in those hours.
One caveat.
Projectors are not great for during the day tv watching, like the news. Even if the brightness has greatly improved, they are still a bit washed off in plain daylight.
Since we don't have cable, nor watch TV here at my house, and only used for movies or binge watching TV series, we don't really care.
Like I said, I'd never go back to a TV.
I'm still on a 1080 projector, and still quite a few hours to go before the end of the bulb life. By that time, maybe 8k, or even 16k will be all the rage.
Touch a button and they drop down!
If you don't want to bother with a screen, they sell pigmented paint, and you'd just need to paint the wall it is projected on.
Light bulbs in projectors also have come a long way. There's some with 5,000 to even 10,000 hours of life.
I love watching movies, but it will take a long time to fill in those hours.
One caveat.
Projectors are not great for during the day tv watching, like the news. Even if the brightness has greatly improved, they are still a bit washed off in plain daylight.
Since we don't have cable, nor watch TV here at my house, and only used for movies or binge watching TV series, we don't really care.
Like I said, I'd never go back to a TV.
I'm still on a 1080 projector, and still quite a few hours to go before the end of the bulb life. By that time, maybe 8k, or even 16k will be all the rage.
But how do you choose between a finite (CBT) and an infinite (floor to ceiling) array?
It occurred to me that the curved CBT placed out from the wall might gain some measure of immunity from front wall boundary nulls by virtue of its curvature and that might be compelling - at least until you weigh in construction difficulties.
It occurred to me that the curved CBT placed out from the wall might gain some measure of immunity from front wall boundary nulls by virtue of its curvature and that might be compelling - at least until you weigh in construction difficulties.
Having heard Keele's CBTs twice in different locations, I can say that they are very nice, do what they claim and people really like them. However, they have a serious limitation that rarely gets mentioned. Power handling.
Because of the amplitude shading some drivers are taking much more of the load than others. And in the first model demonstrated you could smell the resistors getting hot! The unequal power distribution among the drivers means that for good SPL some of the small drivers are working much harder than they should, and that's audible.
In an A/B comparison with Danely's SH50 speakers, the CBT pales in every measure. Cleanliness, imaging, tonality, ease of dynamics and more. But that's not really a fair fight, the CBT is a very small speaker and does punch above its weight.
Not using amplitude shading is going to be a huge advantage for clean SPL and dynamics simply because the drivers don't have to work as hard.
Because of the amplitude shading some drivers are taking much more of the load than others. And in the first model demonstrated you could smell the resistors getting hot! The unequal power distribution among the drivers means that for good SPL some of the small drivers are working much harder than they should, and that's audible.
In an A/B comparison with Danely's SH50 speakers, the CBT pales in every measure. Cleanliness, imaging, tonality, ease of dynamics and more. But that's not really a fair fight, the CBT is a very small speaker and does punch above its weight.
Not using amplitude shading is going to be a huge advantage for clean SPL and dynamics simply because the drivers don't have to work as hard.
Some form of frequency dependent shading on a floor to ceiling array might work. If I would consider anything, that would be it.
Leave anything under 2 KHz running full power and shade above that on the outer (upper and lower) drivers in groups. Leave about 4/5 drivers full power at average listening height. It might even need less power overall to get higher SPL at those higher frequencies that way (less interference), but less drivers would be used to achieve the SPL level.
Leave anything under 2 KHz running full power and shade above that on the outer (upper and lower) drivers in groups. Leave about 4/5 drivers full power at average listening height. It might even need less power overall to get higher SPL at those higher frequencies that way (less interference), but less drivers would be used to achieve the SPL level.
I'm surprised you suggest 2 khz as the starting point. I would have guessed lower; haven't really thought about it until now. My starting point would be to look where the array would be excursion limited if shaded, likely 300 Hz or so and below, depending on the size of the drivers. If the 2 khz is where the lobing that shading eliminates would start, then you have most of the decade to crossover from shaded to unshaded and likely can do that with a few L's and C's
But my quandary is more basic. If I had unobstructed corners or front wall, I wouldn't hesitate to place floor to ceiling line arrays right on or in them. But I need to pull my LAs out into the room for no other reason than to get out in front of artwork and furniture. Then boundary interference becomes an issue. But the delta travel distance of reflections from each driver in a curved CBT to a listener is different. It seems to me that would smooth out the boundary interference and remove the need for absorption on the front wall (WAF issue), but I haven't heard that mentioned in any of these discussions.
But my quandary is more basic. If I had unobstructed corners or front wall, I wouldn't hesitate to place floor to ceiling line arrays right on or in them. But I need to pull my LAs out into the room for no other reason than to get out in front of artwork and furniture. Then boundary interference becomes an issue. But the delta travel distance of reflections from each driver in a curved CBT to a listener is different. It seems to me that would smooth out the boundary interference and remove the need for absorption on the front wall (WAF issue), but I haven't heard that mentioned in any of these discussions.
If you need to have the arrays further out into the room, plus not being able to treat nearby walls than CBT might be your best option.
The way a straight array averages out the common reflections from the ceiling and floor is very similar to what the arced/bent array can do with near (though not too near(!)) walls. I may not have mentioned that in this thread, as I'm dealing with a straight array but have said so on more than one occasion in CBT discussions. I usually got a reaction though, even from the owner of a CBT. There are big differences between one big reflection or multiple smaller ones that happen within differing time intervals.
However, I've seen the impulse of a CBT in a reasonable room and that proved my hunch. I've asked to see more impulses from CBT owners/builders but somehow most people are hesitant to show listening position impulses/plots.
I warn just about every (straight) array builder about the effect of parallel planes to the arrays. A bent CBT does not have those same problems and could be a valid solution when it's pulled out into the room and if one has limited options to treat walls.
The question remains if you should build a multi-way array or if you can get away with an array of full range drivers. I'd take the gamble on that last one.
In all cases you'll need low frequency support if the arrays are pulled away from the walls (or if you have a big room).
P.S. the 2 KHz number comes from what I see in my plots, the onset of the effects of combing does not start until ~6 KHz at my listening distance (it is highly dependent on distance from the speaker). My drivers begin to beam at ~3 KHz so I'd start around there or a bit lower. Around 2 KHz also is where we have the strongest cross talk effects within a conventional Stereo setup. (difference in) Distance from each group of drivers to the ear could be another way to look at it though.
The way a straight array averages out the common reflections from the ceiling and floor is very similar to what the arced/bent array can do with near (though not too near(!)) walls. I may not have mentioned that in this thread, as I'm dealing with a straight array but have said so on more than one occasion in CBT discussions. I usually got a
reaction though, even from the owner of a CBT. There are big differences between one big reflection or multiple smaller ones that happen within differing time intervals.However, I've seen the impulse of a CBT in a reasonable room and that proved my hunch. I've asked to see more impulses from CBT owners/builders but somehow most people are hesitant to show listening position impulses/plots.
I warn just about every (straight) array builder about the effect of parallel planes to the arrays. A bent CBT does not have those same problems and could be a valid solution when it's pulled out into the room and if one has limited options to treat walls.
The question remains if you should build a multi-way array or if you can get away with an array of full range drivers. I'd take the gamble on that last one.
In all cases you'll need low frequency support if the arrays are pulled away from the walls (or if you have a big room).
P.S. the 2 KHz number comes from what I see in my plots, the onset of the effects of combing does not start until ~6 KHz at my listening distance (it is highly dependent on distance from the speaker). My drivers begin to beam at ~3 KHz so I'd start around there or a bit lower. Around 2 KHz also is where we have the strongest cross talk effects within a conventional Stereo setup. (difference in) Distance from each group of drivers to the ear could be another way to look at it though.
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Thanks.
I have been evaluating small full range drivers. My favorite of the moment is Fountek FR58EX. 32 of them spaced at 2.5" get comfortably into subwoofer territory; 24 for a CBT would only be a db or so behind. Subwoofers not optional.
The FR58 with EQ gets by with very little volume. The array can have 4"x4" cross section, nothing that would loom large in the room.
I have been evaluating small full range drivers. My favorite of the moment is Fountek FR58EX. 32 of them spaced at 2.5" get comfortably into subwoofer territory; 24 for a CBT would only be a db or so behind. Subwoofers not optional.
The FR58 with EQ gets by with very little volume. The array can have 4"x4" cross section, nothing that would loom large in the room.
I need to look at the sum of the shading coefficients and scale the number of drivers in my simulation accordingly to see where I would hit excursion limit when shading. With half the drivers on I would be good down to 100 Hz at 110 db output power, per Hornresp. That suggests with stereo subs and a 125 hz XO to the subs, I wouldn't need freq dep shading.
Wesayso,
If you do decide to go for a projector and you're on a budget, have a good read of this website for a great, affordable screen :DIY Screen Section - AVS Forum | Home Theater Discussions And Reviews. In particular, Spandex.
Happy New Year!
If you do decide to go for a projector and you're on a budget, have a good read of this website for a great, affordable screen :DIY Screen Section - AVS Forum | Home Theater Discussions And Reviews. In particular, Spandex.
Happy New Year!