>>> A bit OT...could you please make some pictures of these room treatments?
>>> I just want to see how those bare walls look after a treatment. I will maybe need to >>> treat my room as well, so just wanted to see how it turned out in your case-(WAF >>> acceptable?)
>>> Regards,
>>> Vix
http://www.zillaspeak.com/systems.asp
Room treatments are pretty much out of the way. Ceiling tile is placed on the side walls, front and back. Probably the most effective treatment is not in the picture – it is off to the right. It’s a 2x4 foot – picture frame – of fiberglass two and a half inches thick. This minimized the echo drastically in the listening position. My kids were amazed how the echo disappeared from the room once everything was in place. Sitting in the listening position I can move the fiberglass picture frame out of the room, clap and hear the echo ring – hang the fiberglass back on the wall – clap and the echo is gone. Wife was even surprised – but she was annoyed about the fiberglass and how it may hurt the kiddies. I will wrap it with grill cloth.
Just putting the tiles on the side walls did not make much of an impact. Adding tile to the front and rear walls plus the side tiles made the room very listenable but still had a small amount of slap echo. Adding the fiberglass picture frame seems to be all that was needed to make the room practically disappear. I plan to replace the tile on the front and rear wall with 2x4 foot rugs to be more decorative. Fiberglass made the most impact seemingly quieting the room as soon as it was hung on the wall. I will take pictures and document how the fiberglass picture frame was made. Its easy – fiberglass, peg board 2x4 foot, pine wood frame and some speaker grill fabric to wrap the fiberglass. $32 total and a couple hours.
>>> I just want to see how those bare walls look after a treatment. I will maybe need to >>> treat my room as well, so just wanted to see how it turned out in your case-(WAF >>> acceptable?)
>>> Regards,
>>> Vix
http://www.zillaspeak.com/systems.asp
Room treatments are pretty much out of the way. Ceiling tile is placed on the side walls, front and back. Probably the most effective treatment is not in the picture – it is off to the right. It’s a 2x4 foot – picture frame – of fiberglass two and a half inches thick. This minimized the echo drastically in the listening position. My kids were amazed how the echo disappeared from the room once everything was in place. Sitting in the listening position I can move the fiberglass picture frame out of the room, clap and hear the echo ring – hang the fiberglass back on the wall – clap and the echo is gone. Wife was even surprised – but she was annoyed about the fiberglass and how it may hurt the kiddies. I will wrap it with grill cloth.
Just putting the tiles on the side walls did not make much of an impact. Adding tile to the front and rear walls plus the side tiles made the room very listenable but still had a small amount of slap echo. Adding the fiberglass picture frame seems to be all that was needed to make the room practically disappear. I plan to replace the tile on the front and rear wall with 2x4 foot rugs to be more decorative. Fiberglass made the most impact seemingly quieting the room as soon as it was hung on the wall. I will take pictures and document how the fiberglass picture frame was made. Its easy – fiberglass, peg board 2x4 foot, pine wood frame and some speaker grill fabric to wrap the fiberglass. $32 total and a couple hours.
Hi Jeff,
>>she was annoyed about the fiberglass and how it may hurt the kiddies. I will wrap it with grill cloth.<<
OK, maybe it's just because she's a mother and I'm a wuzz - but there's still an uneasy feeling. It's the microscopically tiny fragments of fiberglass that do the real damage, and for that size grill cloth is not too much of an obstacle. Use rockwool or (even better re peace of mind) cotton.
Seeya,
Pit
>>she was annoyed about the fiberglass and how it may hurt the kiddies. I will wrap it with grill cloth.<<
OK, maybe it's just because she's a mother and I'm a wuzz - but there's still an uneasy feeling. It's the microscopically tiny fragments of fiberglass that do the real damage, and for that size grill cloth is not too much of an obstacle. Use rockwool or (even better re peace of mind) cotton.
Seeya,
Pit
http://www.allproducts.com/qatar/rafco/p16.jpg
Thanks Pit. It's actually coated with a white rubbery material. I think its perfectly safe as long as i frame it out.
If i felt unsafe id remove it.
Thanks Pit. It's actually coated with a white rubbery material. I think its perfectly safe as long as i frame it out.
If i felt unsafe id remove it.
) pages there are the sims and size of BiB's for the 108Sigma and FX120?
using google - think found one refernce by Scottmoose to 108 Sigma - scroll way down this page (maybe FX120 is buried somewhere)
http://www.diyaudio.com/forums/showthread/t-66173-p-3.html
http://www.diyaudio.com/forums/showthread/t-66173-p-3.html
http://www.zillaspeak.com/BIB-RadioShack.asp
I think Scott mentioned a while back (maybe 2500 posts back) the fx120 and 120a could both be used with great results in TCs original BIB box for the RS1354.
I also noted these dims from Scott a while back.
F120a and FX120
Line length 120in. Zdriver 24in. Sl=50in^2
I will try to post these to the BIB page asap.
I think Scott mentioned a while back (maybe 2500 posts back) the fx120 and 120a could both be used with great results in TCs original BIB box for the RS1354.
I also noted these dims from Scott a while back.
F120a and FX120
Line length 120in. Zdriver 24in. Sl=50in^2
I will try to post these to the BIB page asap.
Greets!
Huh! I see where Jeff was going to add the FX120 to the BIB webpage over a year ago, but that's pretty much it other than various folks just talking about it: http://www.diyaudio.com/forums/showthread.php?s=&postid=869489&highlight=#post869489
OK, let's use our ~simple design routine to see how it fares:
Fs = 70 Hz
Vas = 0.29 ft^3
Qts = 0.445
L = 13464.54/2/70 = 96.175"
folded height = 96.175"/2 = 48.09"
Vb = 20*0.29*0.445^1.25 = 2.10804 ft^3
Sm = 2.10804*1728/96.175 = 75.751"^2
depth = SQRT((75.751*SQRT(2)) = 10.35"
width = 75.751/10.35 = 7.319"
zdriver = 96.175*0.217 = 20.87"
a-b-c = 10.35/2 = 5.175"
All dims i.d. and approximate.
A little under-damped, but this doesn't take into account that the net Vb will be somewhat lower, so works for me. Not too shabby IMO for what is basically a big tweeter and should do OK down to 40 Hz if up against a wall. Biggest drawback I see is the low driver position, so adding a mass loaded cavity to space it up seems a good plan.
GM
Huh! I see where Jeff was going to add the FX120 to the BIB webpage over a year ago, but that's pretty much it other than various folks just talking about it: http://www.diyaudio.com/forums/showthread.php?s=&postid=869489&highlight=#post869489
OK, let's use our ~simple design routine to see how it fares:
Fs = 70 Hz
Vas = 0.29 ft^3
Qts = 0.445
L = 13464.54/2/70 = 96.175"
folded height = 96.175"/2 = 48.09"
Vb = 20*0.29*0.445^1.25 = 2.10804 ft^3
Sm = 2.10804*1728/96.175 = 75.751"^2
depth = SQRT((75.751*SQRT(2)) = 10.35"
width = 75.751/10.35 = 7.319"
zdriver = 96.175*0.217 = 20.87"
a-b-c = 10.35/2 = 5.175"
All dims i.d. and approximate.
A little under-damped, but this doesn't take into account that the net Vb will be somewhat lower, so works for me. Not too shabby IMO for what is basically a big tweeter and should do OK down to 40 Hz if up against a wall. Biggest drawback I see is the low driver position, so adding a mass loaded cavity to space it up seems a good plan.
GM
Attachments
>>> Huh! I see where Jeff was going to add the FX120 to the BIB webpage over a year ago...
It feels like just a few weeks ago to me. Sorry for the delay. I think i mostly put BIB dims up if i had a chart to go with it originally. Then i started adding whatever Scott fed me. I may have missed a handful.
Godzilla
It feels like just a few weeks ago to me. Sorry for the delay. I think i mostly put BIB dims up if i had a chart to go with it originally. Then i started adding whatever Scott fed me. I may have missed a handful.
Godzilla
Godzilla said:
Greets!
Thanks, missed this in my search. Anyway, I did the design primarily to get the routine documented in the thread and it's a good one for reasonable power handling, but if what you see in this sim is loud enough plus any room/boundary gain and a second speaker, then I agree, build the original BIB:
GM
Attachments
While I would never sing the praises of fiberglass, I haven't seen anything that would cause me to see it as a major health danger. I worked in surfboard shops forty-plus years ago, making and selling surfboards, and other than the awful itchiness at the end of the day, I have had no health issues from it since then, nor have friends who have remained in the business and other friends who worked in boat-building. The worst side effect in the surfboard industry was to shapers who breathed in too much dust from shaping polyurethane foam blanks, and those who breathed too many fumes from uncured or curing polyester resin. I've also heard little about this being a major health issue with people who handle or install fiberglass insulation. Maybe it's out there, but I haven't seen it. That said, the discomfort factor is enough to get me to use other materials when they will work as well, and I would use caution with fiberglass anyway, though I'm not afraid of the stuff the way some people seem to be. It's certainly not the health threat that asbestos is, and most of the people affected by asbestos were people who worked with it all day long, day in and day out, not those who were casually exposed to it. It seems we may be getting to the point of being afraid to leave our houses, which are probably more dangerous than most of the things we face outside (except traffic). Just be cautious, not stupid, with it.
berm,
right, I have to agree on all counts - and, being a 40 cigs per day man, I shouldn't preach about cancer risks. But still, when there is a way to avoid the stuff, why not.
The hystery about health risks stems from the way life in academic circles works, anyway. It's "publish or perish" - a new cure takes years before getting FDA approval, but a new way to cause sickness can be published right away. So mineral water can cause cancer? Yes, it can. Just reduce it to the solids content and feed your lab rats the equivalent of a few cu.m. per day. Bingo! You can publish and the media will be only too happy to spread the news.
Maybe some benighted healthnazi will pick up your post and develop a theory about the constant itch being a mental hazard?
Seeya,
Pit
right, I have to agree on all counts - and, being a 40 cigs per day man, I shouldn't preach about cancer risks. But still, when there is a way to avoid the stuff, why not.
The hystery about health risks stems from the way life in academic circles works, anyway. It's "publish or perish" - a new cure takes years before getting FDA approval, but a new way to cause sickness can be published right away. So mineral water can cause cancer? Yes, it can. Just reduce it to the solids content and feed your lab rats the equivalent of a few cu.m. per day. Bingo! You can publish and the media will be only too happy to spread the news.
Maybe some benighted healthnazi will pick up your post and develop a theory about the constant itch being a mental hazard?
Seeya,
Pit
health risks
Hi Pit,
Actually I should have said the itch occurred only when working with the stuff for awhile and on the same day, and it usually disappeared after a good shower, though sometimes there was a residual itch. At the end of the day we were careful to walk with our arms a bit out from our body so as not to rub too much of it in, prolonging the itch. Never lasted into the next day or even late into that evening, though.
I've seen similar fears expressed about mdf and formaldehyde, but I read about a study after the initial study (the first probably government funded) that did it up right. They looked at embalmers, people who deal with formaldehyde constantly, and found no significant differences between their health and people not exposed to formaldehyde. A similar study was done with linemen (people who work on power lines) and found their health was no worse than a similar population that wasn't exposed to radiation from high power lines. Their biggest health risk was electrocution or falling - or both. I would preach caution in all these things, but have sense about it.
Now Pit, you old stovepipe, you need to cut back on those cigarettes. That's a real hazard. I haven't been posting much these last few years, but I enjoy reading yours, and would like to think they will be appearing for a long time ahead. I've lost too many friends to "demon" tobacco.
Hi Pit,
Actually I should have said the itch occurred only when working with the stuff for awhile and on the same day, and it usually disappeared after a good shower, though sometimes there was a residual itch. At the end of the day we were careful to walk with our arms a bit out from our body so as not to rub too much of it in, prolonging the itch. Never lasted into the next day or even late into that evening, though.
I've seen similar fears expressed about mdf and formaldehyde, but I read about a study after the initial study (the first probably government funded) that did it up right. They looked at embalmers, people who deal with formaldehyde constantly, and found no significant differences between their health and people not exposed to formaldehyde. A similar study was done with linemen (people who work on power lines) and found their health was no worse than a similar population that wasn't exposed to radiation from high power lines. Their biggest health risk was electrocution or falling - or both. I would preach caution in all these things, but have sense about it.
Now Pit, you old stovepipe, you need to cut back on those cigarettes. That's a real hazard. I haven't been posting much these last few years, but I enjoy reading yours, and would like to think they will be appearing for a long time ahead. I've lost too many friends to "demon" tobacco.
One problem having the BIBs in a small listening room is image size. The BIBs throw a very large image which totally overwhelms the room sometimes. For example, James Taylor Live sounds like the musicians are on a stage 50 feet wide. The sound of the audience applauding is huge. This CD has a warm, lush sound. Also on Fleetwood Macs live album Dance, the stage also seems very large. This CD is a bit bright. Sitting in a room I know is 10 feet wide doesn’t help unless I close my eyes and relax. So I need a proper chair for the room. Smaller scale performances can be very convincing. Regina Spektors On the Radio sounds very real putting her and the piano in the room with me. Diana Krall, Eva Cassidy, Holy Cole, also sound scary real. The image the BIBs throw into the room is up, down and all around.
sweet spot
How big is the typical sweet spot for the standard BIB? I would assume it depends on the driver being used. Would the sweet spot remain about the same in different cabinets - i.e. closed, br, mltl, BIB, ob, or could the cabinet open the spot up some? This seems self-explanatory, but then so do many wrong assumptions that I've made. Are there any particular drivers used in the BIBs that give a larger comfortable listening area?
How big is the typical sweet spot for the standard BIB? I would assume it depends on the driver being used. Would the sweet spot remain about the same in different cabinets - i.e. closed, br, mltl, BIB, ob, or could the cabinet open the spot up some? This seems self-explanatory, but then so do many wrong assumptions that I've made. Are there any particular drivers used in the BIBs that give a larger comfortable listening area?
