• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Concrete DIY Line Arrays and Subs

Afflicted

Member
Joined
Dec 7, 2019
Messages
18
Likes
26
Some pictures of some concrete line arrays and concrete subwoofers I built

kinda dove into it with a wish and a prayer but the resulting performance is astounding.
Anyway they are a novelty and might be of some interest.
 

Attachments

  • IMG_0085.jpg
    IMG_0085.jpg
    809.5 KB · Views: 1,054
  • 7C2E78EB-76C0-45C9-A5B8-3A1596C37A20.jpeg
    7C2E78EB-76C0-45C9-A5B8-3A1596C37A20.jpeg
    209.7 KB · Views: 540
OP
A

Afflicted

Member
Joined
Dec 7, 2019
Messages
18
Likes
26
A few pictures of construction
 

Attachments

  • 948E033F-CFE2-44B0-8CA7-E010533F20D0.jpeg
    948E033F-CFE2-44B0-8CA7-E010533F20D0.jpeg
    34 KB · Views: 357
  • 6CB039CA-EC8C-44A5-848A-77B8F8314D3A.jpeg
    6CB039CA-EC8C-44A5-848A-77B8F8314D3A.jpeg
    34.2 KB · Views: 346
  • 2ED99E9C-65A4-49A4-95BC-91C320C55DA9.jpeg
    2ED99E9C-65A4-49A4-95BC-91C320C55DA9.jpeg
    32.2 KB · Views: 365
  • 33D25747-B224-4A96-BB48-EB50F370B39C.jpeg
    33D25747-B224-4A96-BB48-EB50F370B39C.jpeg
    35.2 KB · Views: 349
  • 193DA230-3557-44F2-92B9-76C866B21938.jpeg
    193DA230-3557-44F2-92B9-76C866B21938.jpeg
    31.3 KB · Views: 340
OP
A

Afflicted

Member
Joined
Dec 7, 2019
Messages
18
Likes
26
And the sub
 

Attachments

  • 4149A0FE-7AB7-4C30-AF26-9FDECFDF1ECF.jpeg
    4149A0FE-7AB7-4C30-AF26-9FDECFDF1ECF.jpeg
    105.8 KB · Views: 225
  • BA11EBDA-B924-46FD-91C9-32A106BCD313.jpeg
    BA11EBDA-B924-46FD-91C9-32A106BCD313.jpeg
    117.2 KB · Views: 231
  • 88F76683-D826-4434-A558-69137AE11E2F.jpeg
    88F76683-D826-4434-A558-69137AE11E2F.jpeg
    132.7 KB · Views: 241
  • F620A6EF-9EC4-4FE0-AC6C-FE87D0C22131.jpeg
    F620A6EF-9EC4-4FE0-AC6C-FE87D0C22131.jpeg
    110.4 KB · Views: 224
OP
A

Afflicted

Member
Joined
Dec 7, 2019
Messages
18
Likes
26

Attachments

  • C564CED6-BEDB-4878-8237-6ACA823C7D02.jpeg
    C564CED6-BEDB-4878-8237-6ACA823C7D02.jpeg
    115.3 KB · Views: 201
  • 7491E150-6873-4CFC-8C70-CBDE247A8195.jpeg
    7491E150-6873-4CFC-8C70-CBDE247A8195.jpeg
    118.8 KB · Views: 227
  • 401CE588-068B-476C-B2D1-163CFCCBEEDF.jpeg
    401CE588-068B-476C-B2D1-163CFCCBEEDF.jpeg
    125.9 KB · Views: 237
  • 36E0AA93-F15E-42FD-9BD7-DB3B3CC98938.jpeg
    36E0AA93-F15E-42FD-9BD7-DB3B3CC98938.jpeg
    100 KB · Views: 212

LTig

Master Contributor
Forum Donor
Joined
Feb 27, 2019
Messages
5,760
Likes
9,442
Location
Europe
Some pictures of some concrete line arrays and concrete subwoofers I built

kinda dove into it with a wish and a prayer but the resulting performance is astounding.
Anyway they are a novelty and might be of some interest.
Very nice. What kind of tweeters did you use?
 

bigjacko

Addicted to Fun and Learning
Joined
Sep 18, 2019
Messages
721
Likes
359
Haha, that's crazy amount of material to cut for the mold. Have you made one using mdf or plywood and compare to this one?
 

Ron Texas

Master Contributor
Joined
Jun 10, 2018
Messages
6,078
Likes
8,914
Concrete... very strong stuff.
 
OP
A

Afflicted

Member
Joined
Dec 7, 2019
Messages
18
Likes
26
Haha, that's crazy amount of material to cut for the mold. Have you made one using mdf or plywood and compare to this one?
No but.......the original line array with the ribbons was with MDF cabinets from Newform Research. I wanted a semi elipse x-section, concrete is very easy to shape with a mold And dead quite for resonance. The concrete is post tensioned with 7 rods that run their length keeping the entire structure in permanent compression so they will never crack. The front outer baffle is 6061 aluminum 1/2” thick. They weigh 660 lb each and have very bad WAF but are perfect for my man cave. I cross the ribbons at 1K with a 1st order and the mid/bass at 1200 with 2nd order all passive. The plan is to get another amp and go all digital but I have not been overly excited to try this mainly because of the requirements to go to a multi channel DAC.......frankly, they sound so darn good that you question sanity on spending more money to try and make them questionably “better”. Then again as my member name suggests I am “afflicted”. Cheers
 

Harmonie

Major Contributor
Forum Donor
Joined
May 30, 2020
Messages
1,927
Likes
2,084
Location
France
Amazing !
The finish is beautiful, can't guess from your first post that it's concrete.

Now more concretely:
Did you reinforce the concrete ?

1609336717019.png


Or, like your sub's picture, did you leave the metal? rods inside ?

Why not fiber/fabric reinforcements ?

This thread may open future opportunities ...
 

Martin

Major Contributor
Forum Donor
Joined
Mar 23, 2018
Messages
1,896
Likes
5,536
Location
Cape Coral, FL
The creativity of speaker DIY’ers never ceases to amaze me. Very nice!

Martin
 

LearningToSmile

Senior Member
Joined
Jun 29, 2020
Messages
311
Likes
531
Very clean, ingenious idea to use concrete for the curved enclosure.

I love the subwoofers too, if I'm seeing correctly in those build pictures they are dual opposed drivers? Was the use of the metal plates for baffle and bottom plate something you decided right away, or did you try fully concrete construction and encountered problems?
 
OP
A

Afflicted

Member
Joined
Dec 7, 2019
Messages
18
Likes
26
Amazing !
The finish is beautiful, can't guess from your first post that it's concrete.

Now more concretely:
Did you reinforce the concrete ?

View attachment 102407

Or, like your sub's picture, did you leave the metal? rods inside ?

Why not fiber/fabric reinforcements ?

This thread may open future opportunities ...

there are 1/2” sch 80 pipe running full length with 1/2” threaded rod inside fo both reinforcement but most importantly post tensioning ....as described in previous comment above
 

Attachments

  • D6889491-15D5-4B2A-BE10-E92A3AB4A705.jpeg
    D6889491-15D5-4B2A-BE10-E92A3AB4A705.jpeg
    441.6 KB · Views: 141
OP
A

Afflicted

Member
Joined
Dec 7, 2019
Messages
18
Likes
26
Very clean, ingenious idea to use concrete for the curved enclosure.

I love the subwoofers too, if I'm seeing correctly in those build pictures they are dual opposed drivers? Was the use of the metal plates for baffle and bottom plate something you decided right away, or did you try fully concrete construction and encountered problems?

No, they are not opposed they are single 15” massive Peerless STW-350F-188PR01-04 with dual 7.4” voice coils. the rear hole is later covered with a round steel plate c/w concrete plug using four bolts. The front baffle was steel so it could support the heavy driver and allow each of the 8 hex head fasteners to be directly tapped and threaded.
 
Top Bottom