Concerning this speaker the drivers are mounted in a 1/4" thick open back cardboard box with the following dimensions.
H 36"
D 18"
W 26"
The screen room it is in RF shielded room using copper screen material is 8' tall on the inside with outside dimensions of 10' X 10'.
I am wanting to reduce the size of the speaker.
How would the sound be affected if I take the tweeter and Midax and hang them from the ceiling with the midax under the Klipsch and angle them to where they are pointed at my ear when sitting in a chair 2' from one wall at 5' along the wall and mounting the 12" woofers in a plywood panel of 36" H X 24" W with that panel in the corner sitting on the floor under the midax and tweeter.
H 36"
D 18"
W 26"
The screen room it is in RF shielded room using copper screen material is 8' tall on the inside with outside dimensions of 10' X 10'.
I am wanting to reduce the size of the speaker.
How would the sound be affected if I take the tweeter and Midax and hang them from the ceiling with the midax under the Klipsch and angle them to where they are pointed at my ear when sitting in a chair 2' from one wall at 5' along the wall and mounting the 12" woofers in a plywood panel of 36" H X 24" W with that panel in the corner sitting on the floor under the midax and tweeter.
There's only one way to know for certain and that would be to try the arrangement.
My guess is that, in your unusual environment, a sturdy corner panel could well give superior results to an open back cardboard box.
It would be a most interesting experiment!
P.S. Don't put the woofer slap bang in the middle of the panel - have it nearer to the floor than to the top of the panel.
By putting the woofer close to the floor, the baffle is naturally extended by the floor - its vertical dimension is increased.
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It may be useful to note that both the Goodmans Midax midrange and the tweeter taken from the Klipsch KG4 speaker are horn drivers.
You will not be surprised that your suggestion to Tube Radio went over my head!
I don't know if he was even considering placing the horn midrange driver on a baffle.
I don't know if he was even considering placing the horn midrange driver on a baffle.
I also notice that they are asymmetrical. The small vertical dimension means much is going to spill over from the mouth.
Originally I used a Trebax, but with the properly restored Goodmans XO950/5000-2 crossover and resistors for attenuation of the trebax and midax, the midax sounded rather harsh to my ears. I have two Trebax and if I really wanted to I could sell them and likely get enough from the sale to fund a project or two.
The Midax, however is very smooth sounding.
For the crossover I just played around with resistors for the l-pad on the Midax and tweeter (keeping the impedance 15 ohms) until the drivers sounded balanced with each other and the woofers.
Didn't realize the photo was not able to be seen. I copied and pasted it originally and I couldn't see it as shown in the following photo not realizing that everyone doesn't have dark mode enabled. I saved the photo instead and posted it that way.
The speaker is currently configured like this.
The main issue will be needing a smaller panel that I can bring into work without attracting much attention.
Originally I had bought two 1/2" thick 2' X 2' pieces of plywood to mount the woofers on, however I decided against that when I found the cardboard box.
The plan is to use safety wire and small screw in eye bolts to mount the tweeter and midax.
That said if I were to use two 2' X 2' 1/2" thick plywood panels mounting the woofers near the bottom of each panel and the midax and tweeter above the woofer on the top panel and secure the panels together with bolts and metal strips along each side and a metal strip running along the seam where the two pieces of wood meet would that sound ok? I'm not looking for the ultimate bass response as I know the woofers cannot go down to 20Hz. In the cardboard box the woofers sound decent enough down to 40Hz.
I'm a bit apprehensive about mounting the midax and tweeter on the ceiling as I don't know how it will sound plus I don't know how safe it would be seen where I work.
When I mount the woofers, midax and tweeter I'll mount them from the rear as that will give me a little more room for the bolt holes.
If the two 2' X 2' panels will work, I'll take a third 2' panel and cut it in half and use that to make a base for the speaker so that it can stand upright. I will then take the other half of the panel and cut it in two equal triangle pieces and screw those to the bottom panel and base so that the speaker baffle and base are secured together. To protect the woofers I'll get two 12" speaker grills. I'll also spraypaint the wood semi-gloss black.
The screen room is made up of panels that are wood on the top, bottom, sides and middle with copper screen on the inside and outside. The floor is the same only it has plywood on top of it and maybe on the bottom. I'm guessing it is 3/4" to 1" or whatever is normally used for a sturdy floor.
Provided it will sound ok, doing something like this is good as the speaker will be easy to move given it's individual pieces of wood and can be assembled and disassembled at work.
The Midax, however is very smooth sounding.
For the crossover I just played around with resistors for the l-pad on the Midax and tweeter (keeping the impedance 15 ohms) until the drivers sounded balanced with each other and the woofers.
Didn't realize the photo was not able to be seen. I copied and pasted it originally and I couldn't see it as shown in the following photo not realizing that everyone doesn't have dark mode enabled. I saved the photo instead and posted it that way.
The speaker is currently configured like this.
The main issue will be needing a smaller panel that I can bring into work without attracting much attention.
Originally I had bought two 1/2" thick 2' X 2' pieces of plywood to mount the woofers on, however I decided against that when I found the cardboard box.
The plan is to use safety wire and small screw in eye bolts to mount the tweeter and midax.
That said if I were to use two 2' X 2' 1/2" thick plywood panels mounting the woofers near the bottom of each panel and the midax and tweeter above the woofer on the top panel and secure the panels together with bolts and metal strips along each side and a metal strip running along the seam where the two pieces of wood meet would that sound ok? I'm not looking for the ultimate bass response as I know the woofers cannot go down to 20Hz. In the cardboard box the woofers sound decent enough down to 40Hz.
I'm a bit apprehensive about mounting the midax and tweeter on the ceiling as I don't know how it will sound plus I don't know how safe it would be seen where I work.
When I mount the woofers, midax and tweeter I'll mount them from the rear as that will give me a little more room for the bolt holes.
If the two 2' X 2' panels will work, I'll take a third 2' panel and cut it in half and use that to make a base for the speaker so that it can stand upright. I will then take the other half of the panel and cut it in two equal triangle pieces and screw those to the bottom panel and base so that the speaker baffle and base are secured together. To protect the woofers I'll get two 12" speaker grills. I'll also spraypaint the wood semi-gloss black.
The screen room is made up of panels that are wood on the top, bottom, sides and middle with copper screen on the inside and outside. The floor is the same only it has plywood on top of it and maybe on the bottom. I'm guessing it is 3/4" to 1" or whatever is normally used for a sturdy floor.
Provided it will sound ok, doing something like this is good as the speaker will be easy to move given it's individual pieces of wood and can be assembled and disassembled at work.
And even more sound is going to spill out through the Faraday cage!
I believe the cage wall consists of a wood frame covered by a screen material made up of thin copper wires spaced 1/16" (1.57mm) from each other vertically and horizontally.
Yep the screen looks just like the screen used for windows only it's copper.
Now would a 4' X 2' baffle be ok for two 12" woofers and the midax and tweeter or will it at least make the bass better than the cardboard box does?
The wall the chair is near is against a raceway. The other wall that meets the one wall has a wood panel on the outside that goes from the bottom to a little over 2' high with the door in the middle of that wall. The wall and raceway will reduce the sound leaving the screen room out to the main aisle. The way the speaker is pointed will make the sound come out more down the aisle my desk is on.
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OK, I've now digested your latest design plan, of which the above sentence provides a simplified statement.
Open baffle bass response is highly dependent on baffle positioning in relation to reflecting surfaces like the walls of the room.
The results are also heavily dependent on the characteristics of the woofer, and I believe your woofers are actually full range drivers.
The woofer would ideally have good linear excursion, high Qts (> 0.77), and relatively high resonance frequency Fs (40-60 Hz).
I can't see any way to tell whether the open baffle arrangement would provide adequate bass response in your screen room other than to do some experiments - perhaps initially with one woofer mounted on a 2' x 2' baffle that can be moved around the room.
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The woofers more than likely came from a solid state console which means they were likely designed for an open back cabinet. The woofers have a decent sized whizzer cone so they might have been full range. I'm thinking I got them with 6 4" 21 ohm RCA cone tweeters. I suppose those woofers likely have a higher resonant frequency.
If the speaker doesn't sound as good open baffle I can get more wood then cut it to make full sides and a top so that it then becomes an open back box.
What I may do is cut the holes for the woofers 2" from the bottom of each wood panel unless it would be better to put the woofers as close together as reasonably possible which means the top woofer will be partly on the bottom panel and top panel.
It would be easier to get a 4' X 2' piece of plywood, however that might not fit in my car and would defeat the purpose of being able to be easily disassembled into smaller pieces.
Now if I could find another pair of those RCA woofers I could make a nice stereo open baffle setup at home where I would use a sub for the bass as I have another of the Goodmans crossovers.
Also for the Klipsch tweeters there's replacement diaphragms available that improve their sound so I could likely do that and improve the treble even more.
The biggest improvement in sound has been the little TDA2050 amp board with two being run in bridged mode.
If the speaker doesn't sound as good open baffle I can get more wood then cut it to make full sides and a top so that it then becomes an open back box.
What I may do is cut the holes for the woofers 2" from the bottom of each wood panel unless it would be better to put the woofers as close together as reasonably possible which means the top woofer will be partly on the bottom panel and top panel.
It would be easier to get a 4' X 2' piece of plywood, however that might not fit in my car and would defeat the purpose of being able to be easily disassembled into smaller pieces.
Now if I could find another pair of those RCA woofers I could make a nice stereo open baffle setup at home where I would use a sub for the bass as I have another of the Goodmans crossovers.
Also for the Klipsch tweeters there's replacement diaphragms available that improve their sound so I could likely do that and improve the treble even more.
The biggest improvement in sound has been the little TDA2050 amp board with two being run in bridged mode.
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So I got two of these plywood sheets for the baffle.
https://www.lowes.com/pd/15-32-in-Common-Pine-Sanded-Plywood-Application-as-2-x-2/3043814
One of these plywood sheets for the sides and bottom.
https://www.lowes.com/pd/Unbranded-1-4-in-x-2-ft-x-2-ft-Pine-Sanded-Plywood/5001992857
Three packs of these
https://www.lowes.com/pd/ReliaBilt-ReliaBilt-2-in-Zinc-Plated-Corner-Brace-4-Pack/5003415881
Four of these. One will be mounted on each side of the two pieces of plywood to join them together real good.
https://www.lowes.com/pd/ReliaBilt-1-in-x-1-in-x-0-165-in-Steel-Mending-Brace/5001769343
Satin black spray paint.
https://www.rustoleum.com/product-catalog/consumer-brands/painters-touch-2x-ultra-cover/satin
I'll use nuts and bolts to secure it all together at work.
https://www.lowes.com/pd/15-32-in-Common-Pine-Sanded-Plywood-Application-as-2-x-2/3043814
One of these plywood sheets for the sides and bottom.
https://www.lowes.com/pd/Unbranded-1-4-in-x-2-ft-x-2-ft-Pine-Sanded-Plywood/5001992857
Three packs of these
https://www.lowes.com/pd/ReliaBilt-ReliaBilt-2-in-Zinc-Plated-Corner-Brace-4-Pack/5003415881
Four of these. One will be mounted on each side of the two pieces of plywood to join them together real good.
https://www.lowes.com/pd/ReliaBilt-1-in-x-1-in-x-0-165-in-Steel-Mending-Brace/5001769343
Satin black spray paint.
https://www.rustoleum.com/product-catalog/consumer-brands/painters-touch-2x-ultra-cover/satin
I'll use nuts and bolts to secure it all together at work.
I look forward to photographs of the final assembly and a report on the bass extension attainable when installed in your screen room.
Will post photos while building and test fitting it all together as I cannot fully build it at home given I need to assemble it at work.
The screws that come with the L brackets will be used to both temporarily secure the wood sheets together and mark where the holes need to be drilled for the bolts.
The screws that come with the L brackets will be used to both temporarily secure the wood sheets together and mark where the holes need to be drilled for the bolts.
The drivers will mount from the front and the crossover will mount on the base. There's a metal weight seen in two of these photos.
That's there as it is front heavy and can will tip over without drivers installed.
I should have used the same thickness wood for the side and bottom though, but it was expensive enough as is.
Got the cuts done.
Partially assembled
Front
Rear
I'm thinking of permanently attaching that weight as it will keep the speaker more stable.
I'll use some screws with washers and lock nuts. I like the lock nuts as I don't have to rely on how tight the nut is against the surface to keep the nut tight which is better for the wood as I don't have to worry about damaging it especially with how close some of the screw holes are to the cut out portions.
Will that baffle be good enough for open baffle? Not looking for 20Hz bass response as I'm sure the woofers cannot play that low.
That's there as it is front heavy and can will tip over without drivers installed.
I should have used the same thickness wood for the side and bottom though, but it was expensive enough as is.
Got the cuts done.
Partially assembled
Front
Rear
I'm thinking of permanently attaching that weight as it will keep the speaker more stable.
I'll use some screws with washers and lock nuts. I like the lock nuts as I don't have to rely on how tight the nut is against the surface to keep the nut tight which is better for the wood as I don't have to worry about damaging it especially with how close some of the screw holes are to the cut out portions.
Will that baffle be good enough for open baffle? Not looking for 20Hz bass response as I'm sure the woofers cannot play that low.
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