IDS-25 speaker
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frperdurabo
AK Member
Interesting. Is it a straight line array, or a Bessal array?
Copa1934
My ears are bleeding
Bump. I was just reading Russell's page a moment ago where he talks about his influences and what brought him to the IDS design.
http://www.roger-russell.com/columns/columns.htm
Very cool history and reading. To some it may come across self serving, but still informative. Has anyone auditioned a pair of these?
Rich Andrews
Well-Known Member
I have a pair. What do you want to know?
Rich Andrews
Well-Known Member
Much has been written about, and much testing been done to line array speakers. There are many advantages to a line array. Having said that some people still prefer a point source, others horns and still other prefer electrostatics. I have listened to all the various types and the one I like the best is a line array.
Your concerns about frequency response are not warranted.
All that is really happening with a line array is that the wave front emanating from the array is a cylindric section as opposed to a spheric section ( aka point source) in a traditional 2 or 3 way classic speaker system. By virtue that the line array has a cylindrical wavefront, the loudness drops off linearly with distance as opposed to the logarithmic drop off of a point source speaker.
There have been a few nay-sayers over the years regarding line arrays, but in every case that I have investigated, the negative remarks came from a person who has never actually listened to a well designed line array.
The reason not more of them are around is that they are expensive. Build them yourself and they are expensive. Buy them pre-build and they are even more expensive.
There is more to designing a line array than just tossing some speakers into a tall box. The mounting plate dimensions, driver spacing and more play no small roles in how it performs.
If you want a nice introduction to a line array, go listen to any of the McIntosh XRT speaker systems that have tweeters that extend from the floor to the ceiling. While there, sit on the floor, stand, and sit. The imaging and frequency response is unchanged. It is an eerie experience.
To experience the linear drop off characteristic of the line array, close your eyes and walk slowly to the column. Stop when you think you are 8-12 inches away. 95 times out 100, people will walk right into the array. Those that don't walk into it chicken out.
Where the line array really shines is in imaging. When I listen carefully to a recording I can tell with a high degree of certainty where the microphones were placed. I remember one recording where I had some difficulty placing myself in the symphony hall. After a moment, I realized I was about 20 feet above the seats. I later got a DVD of the concert and indeed the microphones were suspended from the ceiling and about 20 ft in the air. That is the sort of imaging a well designed array will give.
Where the IDS is superior is in coherence of the imaging. The IDS will allow to to precisely place any instrument in a symphony orchestra. Instead of the 1st violin being in an area, you could just point directly to where he/she is standing. Ssme with kettle drums, double basses, etc.
A lot has to do with the recording engineer too. Get a bad recording and the imaging will be miserable. Save for a handful of CDs, all I own are DG recordings. DG knows what they are doing....mostly. Naxos just plain sucks rocks all the way around. About the only thing Naxos is good for is for getting a recoding of obscure music. Lt. Bloombaums concerto for Kazoo and bagpipe could likely be found on Naxos.
Your concerns about frequency response are not warranted.
All that is really happening with a line array is that the wave front emanating from the array is a cylindric section as opposed to a spheric section ( aka point source) in a traditional 2 or 3 way classic speaker system. By virtue that the line array has a cylindrical wavefront, the loudness drops off linearly with distance as opposed to the logarithmic drop off of a point source speaker.
There have been a few nay-sayers over the years regarding line arrays, but in every case that I have investigated, the negative remarks came from a person who has never actually listened to a well designed line array.
The reason not more of them are around is that they are expensive. Build them yourself and they are expensive. Buy them pre-build and they are even more expensive.
There is more to designing a line array than just tossing some speakers into a tall box. The mounting plate dimensions, driver spacing and more play no small roles in how it performs.
If you want a nice introduction to a line array, go listen to any of the McIntosh XRT speaker systems that have tweeters that extend from the floor to the ceiling. While there, sit on the floor, stand, and sit. The imaging and frequency response is unchanged. It is an eerie experience.
To experience the linear drop off characteristic of the line array, close your eyes and walk slowly to the column. Stop when you think you are 8-12 inches away. 95 times out 100, people will walk right into the array. Those that don't walk into it chicken out.
Where the line array really shines is in imaging. When I listen carefully to a recording I can tell with a high degree of certainty where the microphones were placed. I remember one recording where I had some difficulty placing myself in the symphony hall. After a moment, I realized I was about 20 feet above the seats. I later got a DVD of the concert and indeed the microphones were suspended from the ceiling and about 20 ft in the air. That is the sort of imaging a well designed array will give.
Where the IDS is superior is in coherence of the imaging. The IDS will allow to to precisely place any instrument in a symphony orchestra. Instead of the 1st violin being in an area, you could just point directly to where he/she is standing. Ssme with kettle drums, double basses, etc.
A lot has to do with the recording engineer too. Get a bad recording and the imaging will be miserable. Save for a handful of CDs, all I own are DG recordings. DG knows what they are doing....mostly. Naxos just plain sucks rocks all the way around. About the only thing Naxos is good for is for getting a recoding of obscure music. Lt. Bloombaums concerto for Kazoo and bagpipe could likely be found on Naxos.
DesertRatt
All Bark, No Bite!
Has anyone attempted a DIY version of such vertical arrays?
audmod01
Super Member
I thought I would post here as I am in the process of constructing a copy of Roger Russell's IDS-25 speakers. I contacted Roger while he was still living and discussed using the Tymphany TC9FD18-08 3 1/2" drivers available from Parts Express. Roger confirmed my choice and noted that the design of these speakers was virtually identical to the more expensive drivers he used in his IDS-25 units. He went on to say that his own son had used the same drivers I had identified in a system that he built for himself. The result was virtually identical to the systems he (Roger) had built in performance. I bought the speakers from Parts Express over a period of time as even at $17 plus some cents per driver was expensive for me in retirement. I bought the drivers in 2016, so the price of the drivers has gone up since then. Total cost for drivers was about $900 at that time.
These drivers had sat in their delivery boxes for the years since then. I just now have bought the necessary plywood and had a cabinet shop cut the vertical strips for me (the shop did it while I waited and did not charge me). The cutting to correct length was done by me at home using a skill saw and a few other tools. The hardest part was correctly spacing the speaker holes in the front panel. I had some difficulty getting the exact spacing between each hole due to hole cutting saw drill bit getting slightly off center from the center punched dimple in the plywood. I managed to compensate using a cylindrical 2" sanding cylinder mounted on my drill press. I used the drill press to cut the initial 3" holes. The sanding cylinder allowed me to enlarge and adjust speaker hole spacing. I took each front panel and test fitted all the speakers and found that mounting them all was not difficult and no speaker was physically interfering with another speaker.
Currently I have the floor base pieces with glue curing. I had just finished the cabinet top and bottom pieces after staging the side pieces and making a poster board template of the trapezoid shape needed. The bottom cabinet piece has an extra companion piece of plywood that has to be glued to it. This piece is double thickness after being glued together and provides extra strength to fasten the cabinet body to the floor bases using 3/8" x 3 1/2" bolts, nuts and washers. The cabinet bottom and tops have to be in place in order to get the front, sides and back to position correctly for assembly. Finishing nails and wood glue are used to assemble the cabinets. Pilot holes will be drilled for each nail used to secure the parts together. I will have to provide some blind-stop material to screw the back sides to the cabinets after installing the speakers and wiring them in place. Foam adhesive backed tape will be used along with screws to hold the back to the cabinets when the rest of the cabinets have already been prepared. There are also 11 reinforcing baffles with 2 1/2" holes to the same shape as the cabinet bottom and top pieces that have to be added to each cabinet and nailed and glued in place. I am going to use 1/2" strand board for those pieces to keep cost down. I have enough left over strand board from another project that will be used for those baffles.
I estimate that the total cost will be under $2K. That's still more expensive than any other speakers I have. Sadly, I think that Rich Andrews may have passed away. I noted from one of his posts that he lived in North Texas. I also live in North Texas. I hope to finish these speakers within this month if all goes well and give them a test. I have a David Hafler 10-band equalizer I can use with these speakers instead of the McIntosh unit Roger used. The will be operating with my Dynakit PAS-3X and Stereo-70 system.
These drivers had sat in their delivery boxes for the years since then. I just now have bought the necessary plywood and had a cabinet shop cut the vertical strips for me (the shop did it while I waited and did not charge me). The cutting to correct length was done by me at home using a skill saw and a few other tools. The hardest part was correctly spacing the speaker holes in the front panel. I had some difficulty getting the exact spacing between each hole due to hole cutting saw drill bit getting slightly off center from the center punched dimple in the plywood. I managed to compensate using a cylindrical 2" sanding cylinder mounted on my drill press. I used the drill press to cut the initial 3" holes. The sanding cylinder allowed me to enlarge and adjust speaker hole spacing. I took each front panel and test fitted all the speakers and found that mounting them all was not difficult and no speaker was physically interfering with another speaker.
Currently I have the floor base pieces with glue curing. I had just finished the cabinet top and bottom pieces after staging the side pieces and making a poster board template of the trapezoid shape needed. The bottom cabinet piece has an extra companion piece of plywood that has to be glued to it. This piece is double thickness after being glued together and provides extra strength to fasten the cabinet body to the floor bases using 3/8" x 3 1/2" bolts, nuts and washers. The cabinet bottom and tops have to be in place in order to get the front, sides and back to position correctly for assembly. Finishing nails and wood glue are used to assemble the cabinets. Pilot holes will be drilled for each nail used to secure the parts together. I will have to provide some blind-stop material to screw the back sides to the cabinets after installing the speakers and wiring them in place. Foam adhesive backed tape will be used along with screws to hold the back to the cabinets when the rest of the cabinets have already been prepared. There are also 11 reinforcing baffles with 2 1/2" holes to the same shape as the cabinet bottom and top pieces that have to be added to each cabinet and nailed and glued in place. I am going to use 1/2" strand board for those pieces to keep cost down. I have enough left over strand board from another project that will be used for those baffles.
I estimate that the total cost will be under $2K. That's still more expensive than any other speakers I have. Sadly, I think that Rich Andrews may have passed away. I noted from one of his posts that he lived in North Texas. I also live in North Texas. I hope to finish these speakers within this month if all goes well and give them a test. I have a David Hafler 10-band equalizer I can use with these speakers instead of the McIntosh unit Roger used. The will be operating with my Dynakit PAS-3X and Stereo-70 system.
audmod01
Super Member
I progressed far enough to be able to test my DIY IDS-25 speakers. They do indeed produce the listening results mentioned by Rich Andrews. Currently I am in the process of completing the installation of the 22 baffles in the cabinets. Each cabinet has 11 baffles mounted horizontally to help eliminate resonances in the sides of the cabinets. I am using the David Haefler DH-160 equalizer between my Dynakit PAS-3X preamp and my Dynakit ST-70 amplifier It is only boosting bass below 80Hz or so. Roger Russell used a special McIntosh equalizer with his McIntosh system, which is much more powerful than my Dynakit system. I have no problem listening to my IDS-25 clones using my Dynakit system. Keep in mind that they only need about 1-2 watts to deliver good listening levels in a home environment.
I had a cabinet shop cut the vertical strips needed from two 4' X 8' plywood sheets (I was lucky they did not charge me and did it while I waited). I had additional wood materials at home that I used for reinforcing strips and making the baffles needed. I had bought the Tymphany TC9FD18-08 drivers from Parts Express years ago. I bought sets of them over a period of time so that it did not make a major dent in my monthly budget. I also took advantage of time payments at 0% interest. The Tymphany drivers I selected was done with Roger's approval. They have the same shorting plugs on the voice coil construction that the Vifa drivers that Roger had specified. Their frequency response and sensitivity are very close to the Vifa drivers and also have the rubber cone surrounds like the Vifa drivers.
I still have the final assembly and fill material to add before closing the cabinets up. I my implementation the cabinet backs are removable for service access if needed in the future. Other than that, most of the construction was following Roger's methods. I used wood glue and 1 1/4" finishing nails as the front and sides were assembled. Most all the pieces remained in wood-clamped condition for at least 24 hours before clamps were removed.
I did decide to round the corners of the bases as I could imagine stubbing my feet against sharp corners! The baffles have notches at the rear edge to allow clearance for vertical 3/4" X 1/2" stock which will be used to secure the rear covers. There will also be foam weatherstrip tape between the rear covers and the back of the cabinets. The systems are sealed units. I had to find substitutes for the resettable fuse resistors that Roger had specified. The specifications are not difficult to locate through Digikey or Mouser. The #1157 automobile 12V lamps are easy to locate at any auto parts stores. My total cost is coming in under $2000.
I still have the wire mesh and the tile edging to buy from a hardware supply. I am thinking of using stainless steel wire mesh of 10 mesh per inch instead of the plastic mesh Roger used. The wire mesh will be more open and help protect the drivers better. We currently have no pets, but we did have a cat years ago and they are curious creatures that like to climb, explore and also scratch on vertical surfaces. I could just see one scratching the drivers to pieces!
I had a cabinet shop cut the vertical strips needed from two 4' X 8' plywood sheets (I was lucky they did not charge me and did it while I waited). I had additional wood materials at home that I used for reinforcing strips and making the baffles needed. I had bought the Tymphany TC9FD18-08 drivers from Parts Express years ago. I bought sets of them over a period of time so that it did not make a major dent in my monthly budget. I also took advantage of time payments at 0% interest. The Tymphany drivers I selected was done with Roger's approval. They have the same shorting plugs on the voice coil construction that the Vifa drivers that Roger had specified. Their frequency response and sensitivity are very close to the Vifa drivers and also have the rubber cone surrounds like the Vifa drivers.
I still have the final assembly and fill material to add before closing the cabinets up. I my implementation the cabinet backs are removable for service access if needed in the future. Other than that, most of the construction was following Roger's methods. I used wood glue and 1 1/4" finishing nails as the front and sides were assembled. Most all the pieces remained in wood-clamped condition for at least 24 hours before clamps were removed.
I did decide to round the corners of the bases as I could imagine stubbing my feet against sharp corners! The baffles have notches at the rear edge to allow clearance for vertical 3/4" X 1/2" stock which will be used to secure the rear covers. There will also be foam weatherstrip tape between the rear covers and the back of the cabinets. The systems are sealed units. I had to find substitutes for the resettable fuse resistors that Roger had specified. The specifications are not difficult to locate through Digikey or Mouser. The #1157 automobile 12V lamps are easy to locate at any auto parts stores. My total cost is coming in under $2000.
I still have the wire mesh and the tile edging to buy from a hardware supply. I am thinking of using stainless steel wire mesh of 10 mesh per inch instead of the plastic mesh Roger used. The wire mesh will be more open and help protect the drivers better. We currently have no pets, but we did have a cat years ago and they are curious creatures that like to climb, explore and also scratch on vertical surfaces. I could just see one scratching the drivers to pieces!
Attachments
audmod01
Super Member
Before beginning I read through Roger's article several times to get a general understanding of the sequences to assembling the IDS-25 speaker systems.
I used some thin foam adhesive backed tape on the back side of the outer plastic flange beyond the rubber cone surrounds of each speaker. This has to be added so that these particular drivers get a good air tight seal against the front side of the front panel. I used 1/4" wide by 1/16" thick Yotage tape from Amazon. One package had two rolls, Two packages would have been better when I began to use it on the back of the cabinet.
The bases were made from four pieces of the same plywood used for the rest of the cabinets. They are 14" X 12" and two pieces are glued together for each base. I found a Forstner bit that was the next size larger than the flat washers Roger specified. The bottom of each cabinet also consists of two pieces of 3/4" plywood glued together. those have to be positioned against the bases and clamped together while a drill goes through the bases and the cabinet bottoms so that the bolts that hold the cabinets to the bases will line up correctly when the bases are to be fastened to the cabinets. I used a drill press so that the drill bit would pass through the parts at a perfect 90 degree angle to the flat surfaces of the parts. Check the penetration of the Forstner bit and stop drilling the recess for the bolt heads when the stack-up of the lock washer and flat washer on them can be tightened and the bolt heads will not protrude enough to scratch floors when the cabinets are joined to the bases. Several assembly and disassembly efforts may be needed to determine the exact amount of drilling needed using the Forstner bit.
When Roger Russell wrote the article in the July 2006 issue of AudioXpress magazine he gave many details of the construction of the IDS-25 cabinets. Complete dimensions are shown and a list of materials was provided. Small finishing nails were mentioned and I was able to find those at a hardware store. I first experimented by driving the finishing nails into some scrap pieces of the same plywood used for the cabinets. I discovered these very small finishing nails were very easy to bend while nailing. I found the smallest size drill bit that was smaller than the OD of the nails. The drill bit was so small in OD that it would not fit my 1/2" drill chuck, so, I tried the bit in my Dremel tool. The bit was smaller than the smallest collet I had! I wound up wrapping the small drill bit shank with a piece of adhesive backed copper tape I had on hand and was able to use the Dremel tool to drill pilot holes for each nail. I also bought two 16oz. containers of wood glue. In assessing the situation, I realized that I would have to mount the speakers to the front panel first, then use the bottom and top of the cabinets to establish the angles of the two sides as they are attached with glue & nails to the edges of the front panel. As speakers are mounted, be sure to drill pilot holes for the speaker mounting screws to avoid causing splits in the plywood and possible raised surface of the front panel to interfere with the flatness of the speaker frame. Use a suitable nail-set to drive the nail heads below the surface of the plywood, then add some wood putty or spackling compound to cover them up. Make sure that panels remain properly aligned and flush as you drill pilot holes and drive the nails in.
With the front panel (speakers mounted) I carefully added glue to the edges of the front panel, then brought the two sides and the top and bottom in place and clamped them together with several types of clamps I had. I quickly drilled the holes for the finishing nails and drove them in on both sides of the front panel. I let the pieces remain clamped while the glue had 24 hours to cure. Once that was done I added glue to the edges of the top and bottom and drilled holes for finishing nails to secure them to the sides followed by another 24 hour curing time for the glue.
At this stage I wired the speakers, being very careful to follow the correct connections and observing the polarity of the speakers as I did so. When I finished that work, I took time to use nylon cable ties to keep the wires organized in a straight line. I used somewhat shorter dimensions for the connection wires than Roger called for. I realized that when the baffles were to be installed that unless I provided a channel in them to pass the wire through that the baffles would not seat flush with the back side of the front panel. I cut the 22 baffles and drilled the two 2 1/2" holes in each one as Roger described. I gathered all the baffles together and clamped them together so that the back edges were against a work table. I used a router to make a 1/2" wide by 1" deep channel in the front edges of the baffle stack. This allowed each baffle to slip over the wires of the speakers as I inserted them into the cabinets. You can see the slot in the front edge of the example baffle shown in the previous post. Roger may have passed the wires he used through the 2 1/2" holes in the baffles, but, space is so tight that I could not see a way to physically get the soldering operations done with baffles in place.
The next step was to add the vertical reinforcing ribs to the rear edge of the sides, allowing the necessary 3/4" inset for the back panel to fit into the back of the cabinets. After those parts were nailed and glued to the sides it was time to add the baffles. Since I was using strand board, I decided to add reinforcing 1/2" X 3/4" X 6 1/2" ribs under each baffle on the sides of the cabinet. That meant that I had to cut 44 pieces of that size. I used my mitre/cut-off saw for that. Those were also glued in place and glue allowed to cure for 24 hours.
I will use countersunk #8 X 1" brass wood screws with Phillips heads to fasten the cabinet backs to the rest of the cabinets. The protective auto-reset fuse resistors were assembled with the #1157 lamps and dual banana connectors on a piece of masonite as Roger described. However I used a slightly different mounting method than he did. If you decide to make your own you may make slight alterations in this area. I had a tube of clear flexible-when- cured glue that I used to secure the lamps (Lexel which sticks to just about anything). RTV silicone or similar can also be used. When attaching the wires from the speakers, make sure you have those wires long enough so that the back of the cabinet can be removed a short distance for service needs in the future.
I am using the thin (about 1/16"" thick foam weatherstrip that is about 1/4" wide to provide a seal between the back cover and the vertical reinforcing ribs attached to the side panels and the back edges of the baffles. Make sure that the back edges of the baffles do not protrude back beyond the back surface of the vertical reinforcing ribs. You may need to sand down some baffle rear edges until the back cover will fit well against the back of the cabinet. If you do not want to use weatherstrip on the back edges of the baffles, you may use some strips of felt about 1/16" thick to prevent the cabinet back from vibrating against the baffles.
I used some thin foam adhesive backed tape on the back side of the outer plastic flange beyond the rubber cone surrounds of each speaker. This has to be added so that these particular drivers get a good air tight seal against the front side of the front panel. I used 1/4" wide by 1/16" thick Yotage tape from Amazon. One package had two rolls, Two packages would have been better when I began to use it on the back of the cabinet.
The bases were made from four pieces of the same plywood used for the rest of the cabinets. They are 14" X 12" and two pieces are glued together for each base. I found a Forstner bit that was the next size larger than the flat washers Roger specified. The bottom of each cabinet also consists of two pieces of 3/4" plywood glued together. those have to be positioned against the bases and clamped together while a drill goes through the bases and the cabinet bottoms so that the bolts that hold the cabinets to the bases will line up correctly when the bases are to be fastened to the cabinets. I used a drill press so that the drill bit would pass through the parts at a perfect 90 degree angle to the flat surfaces of the parts. Check the penetration of the Forstner bit and stop drilling the recess for the bolt heads when the stack-up of the lock washer and flat washer on them can be tightened and the bolt heads will not protrude enough to scratch floors when the cabinets are joined to the bases. Several assembly and disassembly efforts may be needed to determine the exact amount of drilling needed using the Forstner bit.
When Roger Russell wrote the article in the July 2006 issue of AudioXpress magazine he gave many details of the construction of the IDS-25 cabinets. Complete dimensions are shown and a list of materials was provided. Small finishing nails were mentioned and I was able to find those at a hardware store. I first experimented by driving the finishing nails into some scrap pieces of the same plywood used for the cabinets. I discovered these very small finishing nails were very easy to bend while nailing. I found the smallest size drill bit that was smaller than the OD of the nails. The drill bit was so small in OD that it would not fit my 1/2" drill chuck, so, I tried the bit in my Dremel tool. The bit was smaller than the smallest collet I had! I wound up wrapping the small drill bit shank with a piece of adhesive backed copper tape I had on hand and was able to use the Dremel tool to drill pilot holes for each nail. I also bought two 16oz. containers of wood glue. In assessing the situation, I realized that I would have to mount the speakers to the front panel first, then use the bottom and top of the cabinets to establish the angles of the two sides as they are attached with glue & nails to the edges of the front panel. As speakers are mounted, be sure to drill pilot holes for the speaker mounting screws to avoid causing splits in the plywood and possible raised surface of the front panel to interfere with the flatness of the speaker frame. Use a suitable nail-set to drive the nail heads below the surface of the plywood, then add some wood putty or spackling compound to cover them up. Make sure that panels remain properly aligned and flush as you drill pilot holes and drive the nails in.
With the front panel (speakers mounted) I carefully added glue to the edges of the front panel, then brought the two sides and the top and bottom in place and clamped them together with several types of clamps I had. I quickly drilled the holes for the finishing nails and drove them in on both sides of the front panel. I let the pieces remain clamped while the glue had 24 hours to cure. Once that was done I added glue to the edges of the top and bottom and drilled holes for finishing nails to secure them to the sides followed by another 24 hour curing time for the glue.
At this stage I wired the speakers, being very careful to follow the correct connections and observing the polarity of the speakers as I did so. When I finished that work, I took time to use nylon cable ties to keep the wires organized in a straight line. I used somewhat shorter dimensions for the connection wires than Roger called for. I realized that when the baffles were to be installed that unless I provided a channel in them to pass the wire through that the baffles would not seat flush with the back side of the front panel. I cut the 22 baffles and drilled the two 2 1/2" holes in each one as Roger described. I gathered all the baffles together and clamped them together so that the back edges were against a work table. I used a router to make a 1/2" wide by 1" deep channel in the front edges of the baffle stack. This allowed each baffle to slip over the wires of the speakers as I inserted them into the cabinets. You can see the slot in the front edge of the example baffle shown in the previous post. Roger may have passed the wires he used through the 2 1/2" holes in the baffles, but, space is so tight that I could not see a way to physically get the soldering operations done with baffles in place.
The next step was to add the vertical reinforcing ribs to the rear edge of the sides, allowing the necessary 3/4" inset for the back panel to fit into the back of the cabinets. After those parts were nailed and glued to the sides it was time to add the baffles. Since I was using strand board, I decided to add reinforcing 1/2" X 3/4" X 6 1/2" ribs under each baffle on the sides of the cabinet. That meant that I had to cut 44 pieces of that size. I used my mitre/cut-off saw for that. Those were also glued in place and glue allowed to cure for 24 hours.
I will use countersunk #8 X 1" brass wood screws with Phillips heads to fasten the cabinet backs to the rest of the cabinets. The protective auto-reset fuse resistors were assembled with the #1157 lamps and dual banana connectors on a piece of masonite as Roger described. However I used a slightly different mounting method than he did. If you decide to make your own you may make slight alterations in this area. I had a tube of clear flexible-when- cured glue that I used to secure the lamps (Lexel which sticks to just about anything). RTV silicone or similar can also be used. When attaching the wires from the speakers, make sure you have those wires long enough so that the back of the cabinet can be removed a short distance for service needs in the future.
I am using the thin (about 1/16"" thick foam weatherstrip that is about 1/4" wide to provide a seal between the back cover and the vertical reinforcing ribs attached to the side panels and the back edges of the baffles. Make sure that the back edges of the baffles do not protrude back beyond the back surface of the vertical reinforcing ribs. You may need to sand down some baffle rear edges until the back cover will fit well against the back of the cabinet. If you do not want to use weatherstrip on the back edges of the baffles, you may use some strips of felt about 1/16" thick to prevent the cabinet back from vibrating against the baffles.
Last edited:
JRhoBurton
All roads lead to music
Nice work.
audmod01
Super Member
I had to cut some edges of the 3/4" thick plywood using a skill saw. My cutting efforts were not the straightest and when some pieces were placed against each other the surfaces were not straight and smooth. I have a stationary belt and disc sander that I used to get the edges smooth and straight and the top and bottom cabinet pieces to be the same exact size. A hand held sander could be used if you don't have a belt sander.
The baffle boards should be made the overall size as the cabinet top and bottom pieces. The rear edges of the ones I made had to have the cutouts for the 1/2" X 3/4" vertical reinforcing ribs to clear the baffle pieces as they are inserted.
When fastening the speakers to the front panel board, be careful not to distort the plastic frame of the speaker. The foam tape backing needs to be compressed slightly, but not so much as to distort the frame. Even speakers with metal frames can be distorted by fasteners if excessive force is used while tightening mounting hardware.
I am not the greatest at cabinet finishing, so instead of staining, sanding and varnish finish I decided to paint the cabinets white. As Roger mentioned in his magazine article, white speaker cabinets are less dominating to look at when placed against white interior walls. Other colors of paint matching the walls of a given room could also be used in order to improve the spouse acceptability factor.
The baffle boards should be made the overall size as the cabinet top and bottom pieces. The rear edges of the ones I made had to have the cutouts for the 1/2" X 3/4" vertical reinforcing ribs to clear the baffle pieces as they are inserted.
When fastening the speakers to the front panel board, be careful not to distort the plastic frame of the speaker. The foam tape backing needs to be compressed slightly, but not so much as to distort the frame. Even speakers with metal frames can be distorted by fasteners if excessive force is used while tightening mounting hardware.
I am not the greatest at cabinet finishing, so instead of staining, sanding and varnish finish I decided to paint the cabinets white. As Roger mentioned in his magazine article, white speaker cabinets are less dominating to look at when placed against white interior walls. Other colors of paint matching the walls of a given room could also be used in order to improve the spouse acceptability factor.
C Hart
Super Member
I just came across the article on Roger's website and then found this thread by Googling. (I don't know how I missed it earlier since I am on AK way too much.) The project and your work looks outstanding and I can only imagine sounds as good as it looks.
I am beginning to think of building a set of these, meaning I am at the top of the slippery slope and sooner or later I will actually start working on them. The drivers are now $23, still not outrageous. But I can't find the article from AudioXpress. Is there an alternate source of specs somewhere?
I am beginning to think of building a set of these, meaning I am at the top of the slippery slope and sooner or later I will actually start working on them. The drivers are now $23, still not outrageous. But I can't find the article from AudioXpress. Is there an alternate source of specs somewhere?
damacman
Resident Psycho
Is that a fact? Rich just kinda' disappeared one day several years ago ...
