peavey 18's

[dan]

Hi all, the good news is I have Peavey sp-2x speakers with 15's and horns and built in crossovers that I like real well. The bad news is I have 18" widows in some really crappy cab's someone built with 1/2" plywood. Can I find some idiot proof cabinet designs for ported enclosures ? I really don't want to learn everything there is to know about speaker design, just want to build a good home for my 18's.

[roddyama]

Hi Dan,

Here’s a link that will gives the T/S parameters for the 18” Black Widow.
http://www.usspeaker.com/peavey%2018018bw-1.htm

I did some calculations. A box of 8cu.ft. (40”H x 24”W x 15”D) with 2 – 4”dia. round ports 5” long will give you an f3 of 46Hz. These dimensions are inside dimensions and you will have to increase them to make up for the bracing driver and port volumes. The link below will take you through the construction of a bass bottom enclosure. You will need to change the dimension for your speaker.
http://www.geocities.com/SunsetStrip...1/speaker.html

Hav fun.
Rodd Yamashita

[dan]

well after fighting with winISD and checking out the resources Rod mentioned, it seems I need to build enclosures about 3.5' x 3.5' x 4'. I intend to locate two vent holes 6" dia under the speaker. planning on 3/4 osb, then sealing joints with silicone and priming the inside. If they sound good I'll have to buy some covering material, already have handles, corners, and TS-TRS inputs. Any advice on bracing and batten ??

[roddyama]

Originally posted by dan
well after fighting with winISD and checking out the resources Rod mentioned, it seems I need to build enclosures about 3.5' x 3.5' x 4'. I intend to locate two vent holes 6" dia under the speaker. planning on 3/4 osb, then sealing joints with silicone and priming the inside. If they sound good I'll have to buy some covering material, already have handles, corners, and TS-TRS inputs. Any advice on bracing and batten ??

Dan,

You’re right about the box size if you’re going for the extended flat response, but that driver is really pretty flexible with regards to box size. You'll have to contend with the traditional trade-offs, the smaller the box the higher the f3 (with a small bump in the response once the box gets below about 10cu.ft.). What do you want to use your system for, critical listening, HT, PA? The point is, you don’t need 24Hz response for PA or a DJ system, and a bass guitar only needs 40Hz. You can get that in 10cu.ft. instead of the refrigerator crate you’re talking about.

For a box that large I would build a frame first out of 2x4’s and screw ¾” plywood skins to the frame. That way all of the bracing is easy to put in place. For the stuffing, you can line the whole inside with about ½” to an 1” of carpet felt with 3 or 4 inch fiberglass insulation over that.

I’m interested in knowing what the application will be.
Rodd Yamashita

[noSmoking]

hi Roddyyama,
Thanks for the info on the 18" black widow,I got them today and cut the wood this afternoon ,I am building the decware's Homewreckers for their new home,The plans I bought were for 15" so I scaled them up a little and made them 24" instead of 20 " , if my cal is correct ,if they are 48" tall and 24" square that's 4 sq feet per foot so = 16cu feet- internal mounts for the speakers and the speakers, I am thinking 15.66 sq feet at finish assembled,Material thickness is 3/4 birch,
The Spec sheet recomended plywood ,The ratings are mind blowing 3200 pkwatts,1600 program,I was real impressed with the cone structure,it was thick and very ridged,and it has a reinforced voice coil and special leads,thought that was neat.

A question ? what is carpet felt? is this the foam they use?Is the fiberglass insul. needed in this box the spec sheet told how to build a box and didn't say anything about insulation,One other it did recommend a active sub bass control unit ,I thought I would ask your opion and look on the site to see what's here!
Thanks for your time!
Cheers

[noSmoking]

close to the smoke test,lol

[noSmoking]

hi,
Glue is still not dry,,,,,
I got a question,does these need any insulation in them ? and what is the proper way to tune them,
I will have active control but would like them to function as natural as I can get them!
Thanks alot,

[noSmoking]

hi
I got some "motor" noise in these subs sounds like a engine at Idle when I was breaking them in with a gen @ 100hz and a 100 watt amp,I beat the box with a hammer and it doesn't make any rattles or such,BTW a good way to find those nasty sounds is to beat the box with a rubber mallet,any Ideas?...did anyone who has built a hwk 18 homewrecker used insulation and did they use the first position to mount the speaker? port sizes? THANKS

[walters]

this thread is from nine years ago. you should start a new one.

[noSmoking]

hi,
Yea but only nine post,lol.
a NAME ...How to low produce low BASS?