Hi Oliver,
If the depth of the cab is worth stretching another inch vs a negligable difference. I do have that room to spare, so go ahead and use that to your advantage, if needed.
If you haven't started yet, don't worry about it. I miscalculated something and 48" is too tall :/ and I'm doubting the other small changes are enough to make it matter... Apologies in advance if you've already been plugging away.
If the depth of the cab is worth stretching another inch vs a negligable difference. I do have that room to spare, so go ahead and use that to your advantage, if needed.
If you haven't started yet, don't worry about it. I miscalculated something and 48" is too tall :/ and I'm doubting the other small changes are enough to make it matter... Apologies in advance if you've already been plugging away.
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Attachments
Very interesting,
I have some stoutly built bass bins of outside dimensions 40" H X 18"W x 24"D and wonder about building a 15" version. 5.5 inches too short for an 18 but a 15" would gain 3 inches of S2. Can I get away with an inside width of 16.5" instead of the 24" width of the 18" version since I'm running the same depth (actually, it is deeper by 1.5" so I can lengthen S2 by another 1.5 inches and get really close)
Yes, I'll struggle my way through horn response to get an idea, but wondered if the Keystone is sensitive to that kind of manipulation?
My initial though is to use the JBL GT5 15" car woofer which uses the
same motor as the GTO 1214--with a larger cone. Since it has a much smaller Vas than traditional PA speakers, can I assume it won't need to be as wide? Final amplification is just 200 watts so not much of a need for a BL product higher than it's rated 16.7 (I'm assuming)
Just a set of bins that do 32 to 150Hz is all I need for the garage, I do have the options of not using the JBL 15 but with 200 watts to play with, no need for B&C monsters either. I would like to generate
121 dB with two of them driven with two 200 watt amplifiers for sound testing at the local church so the closer, the better.
In summation, if I use a 15" and make the path the same length, the depth is the same--can I narrow the cabinet because of the smaller woofer or is that a no go for Keystones? I prefer the Keystone over the typical 18" BR since they are protected from various things behind the keystone panel and prevent teenagers from becoming fascinated by watching woofers stroke (not sure why they do but....) Part of my idiot proofing concept...
Thank you!
I have some stoutly built bass bins of outside dimensions 40" H X 18"W x 24"D and wonder about building a 15" version. 5.5 inches too short for an 18 but a 15" would gain 3 inches of S2. Can I get away with an inside width of 16.5" instead of the 24" width of the 18" version since I'm running the same depth (actually, it is deeper by 1.5" so I can lengthen S2 by another 1.5 inches and get really close)
Yes, I'll struggle my way through horn response to get an idea, but wondered if the Keystone is sensitive to that kind of manipulation?
My initial though is to use the JBL GT5 15" car woofer which uses the
same motor as the GTO 1214--with a larger cone. Since it has a much smaller Vas than traditional PA speakers, can I assume it won't need to be as wide? Final amplification is just 200 watts so not much of a need for a BL product higher than it's rated 16.7 (I'm assuming)
Just a set of bins that do 32 to 150Hz is all I need for the garage, I do have the options of not using the JBL 15 but with 200 watts to play with, no need for B&C monsters either. I would like to generate
121 dB with two of them driven with two 200 watt amplifiers for sound testing at the local church so the closer, the better.
In summation, if I use a 15" and make the path the same length, the depth is the same--can I narrow the cabinet because of the smaller woofer or is that a no go for Keystones? I prefer the Keystone over the typical 18" BR since they are protected from various things behind the keystone panel and prevent teenagers from becoming fascinated by watching woofers stroke (not sure why they do but....) Part of my idiot proofing concept...
Thank you!
The path length will be a bit shorter which will raise the F3 a bit.
That said, I had to reduce the exit size for the 15" to keep a similar LF response as the 2x12" and 18". Reducing the exit size further makes the cabinet go lower, but also drops the level.
Reducing cabinet width may actually be an improvement for a 15", but you will need to experiment with the exit size. As a starting guess, I'd reduce the exit dimensions by the same % as the cabinet width and height are reduced.
Since you have the existing cabinet shells, might as well go for it.
Thank you so much!
As a garage system, the keystone will cover the 15 from flying parts, oil, beer and kids. As you say, I have the shells of stout 3/4" ply and noted the ratio is close to the 18" version. If I can get a gain of efficiency of 3dB over the stock 90dB of the JBL--anything extra is gravy. A pair of those with 200 watts each should be more than enough for BBQs and noise complaints.
Now to practice with horn response, gather up some spare wood and get those 15's on order. Thank you for your assistance and guidance and I'll start making sawdust in a week or two.
With lightweight 3/4" plywood and the BC18SW115 the Keystone came in around 150 pounds.
From what I can tell, BB ranges from around 2.6 to 3 pounds per square foot.
The Keystone with the BC18SW115 should weigh around 175 pounds if the BB is around 3 pounds per square foot, using the the BC18TBW100 instead would add another 7.1 pounds.
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Cutlist
ok, so I have been using Ubuntu for about 1 1/2 years and love it until today. I have cutlist installed via WINE and it will not show solution of the board layouts for the keystone. e Even when i manually drag the boards it freezes up repeatedly. Can someone post the cutlist please??
ok, so I have been using Ubuntu for about 1 1/2 years and love it until today. I have cutlist installed via WINE and it will not show solution of the board layouts for the keystone. e Even when i manually drag the boards it freezes up repeatedly. Can someone post the cutlist please??
allllright. so I've finally convinced a friend to go halfs with me on 4 keystones. We had initially planned to drop the extra cash on the Sw115. Arts indicating it might be more prudent to just go with the tbw100. Weight is not a concern.
All I have available is my xti 4002 (doubtfully useful), and his LG 14000 Clone amp (a suppossed 4500 watts at 4 ohms per channel). I'm more than happy to plug that clone up to a 30 amp or even 50 amp service if need be... the real question is if we can make use of the Sw115s power. If there's no audible difference, I have no issue going with the tbw... the fact that we're getting 4 means I'll get a pretty discount on them (I'd need to get 12 sw115s to get a similar discount).
All I have available is my xti 4002 (doubtfully useful), and his LG 14000 Clone amp (a suppossed 4500 watts at 4 ohms per channel). I'm more than happy to plug that clone up to a 30 amp or even 50 amp service if need be... the real question is if we can make use of the Sw115s power. If there's no audible difference, I have no issue going with the tbw... the fact that we're getting 4 means I'll get a pretty discount on them (I'd need to get 12 sw115s to get a similar discount).
The xti 4002 bridged mono would power one four ohm cabinet nicely
.Whether you would notice the 2 dB difference using a 18SW115-4 driven at 82v compared to a 18TBW100-4 at 64 volts is hard to say.
I don't think I'd notice a difference unless it was an A/B test.
Have fun making sawdust!
Art