Transcendent Sound

Making Music Better

 

FFRS Mark 4:20 i. 

Freaking Fantastic Redneck Subwoofer Mark 4:20 Inspired

or, The Bucket Sub

by Ed Schilling of The Horn Shoppe

Ok peeps, it's time. After minutes of design calculations and 2 prototypes, it's done and good enough to release. Guys, you are going to be dumbfounded at how good this thing is. I do not mean "good for a speaker in a bucket", I mean good compared to very expensive commercial offerings.  No, it does not look as good and it is not small and easily hidden but it makes up for all that in performance and the fact it costs practically nothing and anyone can build it easily. You'll want 2 so just go ahead and order 2 drivers and build them.


So here goes....you will need....

1. Peerless SLS 830667, 8" Paper Cone Woofer

  1. 2.a plate amp with speaker level inputs...

3. 3 feet, one inch in diameter and inch tall

4. some silicone sealant

5. some wire

6. 4 to 8 three inch deck screws

7. one 5 gallon bucket and lid

8. one bag of fast setting concrete.

9. three, 2 inch drywall or wood screws for the feet

10. maybe some small sheet metal or wood screws for the driver.....I did not screw it down on mine but it would not hurt.


Pay attention here as this is extremely difficult and painstakingly hard to do. Not.


1. Turn bucket upside down and use driver to determine the size mounting hole. Cut hole in bottom of bucket. Test the fit. Get another bucket if you screw it up.

2. Using 2 inch screws, screw the feet onto the lid and pound the lid on the bucket making sure it is all the way on, I used a rubber mallet. The cement should anchor the screws and feet

3. Between the lid and the the projection on the bucket drive the 3 inch deck screws in. They are the anchors for the cement. I used 4, use as many as you like.

4. Drill a small hole above the projection on the bucket for the wire to exit. Or install some binding posts if you want it "fancy".

5. Mix the concrete in another container....we don't want it on the inside walls, be neat here! Mix it thoroughly and not too runny!

6. With bucket upside down, carefully pour/scoop cement through the driver hole and fill it just above the projection on the bucket making sure it covers the anchor screws, about 2 to 3 inches deep.

  1. 7.Let it cure at least 3 days.  The moisture is the concrete has to come out before the bucket is sealed.

  2. 8.Solder wire to driver, pass through hole or connect to binding posts and silicone the driver in place, use screws if you want but the silicone will hold it.

9. Seal the wire hole with silicone

10. Hook her up and be amazed

  1. 11.Notice the lack of anything inside, don't screw it up with stuffing! :)


Some additional technical and sonic information from Bruce Rozenblit:


Real time analysis in a typical live listening room shows the Bucket Sub to be essentially flat from 25 Hz to 100Hz.  One Bucket Sub can produce that output up to about 106 dB then it starts running out of steam.  Two should be able to reach at least 109 dB.  That is a tremendous amount of low frequency energy that will cause dishes to rattle and the house to shake.  The sound is smooth, without being boomy or uneven.  Transients are quick and not the least bit mushy.  The relatively small and lightweight cone contributes to its speed.  The Bucket Sub greatly benefits from lots of current drive so a high power class D plate amp is essential.  Performance improves as current drive goes up.  Several hundred watts will get the job done.  Corner placement works well as it is up firing. 


The way the thing works is by taking a speaker that was never intended for pure subwoofer operation and forcing it acoustically and electrically to perform as a super sub.  The massive current drive pushes it in a very linear fashion.  Since it is basically operating out of its intended range, it must be crossed over at low frequencies.  At frequencies above 150 Hz, the output will begin to rise relative to the bottom octaves.  For this reason, its use must be restricted to pure subwoofer operation.  A minimum 12 dB/octave low pass filter is required and 24 dB/octave will increase performance.


Properly adjusted, the Bucket Sub will blend seamlessly into a main speaker system.  It just disappears, except for the low end foundation that it provides.  This is ideal performance for a subwoofer.  This thing can be built for $75 in about one hour.  It is no doubt the greatest value in DIY audio available.