Just trying to beat the rush,
Actually, Mike has his answer as there is a T-TQWT design that uses two 15" woofers and tuned to 8.5 Hz. Loaded in a corner it is over 110dB at 67 watts so 2 of them should hit 120dB with a basic 100 x 2 amplifier in a corner.
http://www.diyaudio.com/forums/subw...ic-subwoofer-digital-organ-2.html#post2884448
The latest exercise in madness is to make the most noise possible for $50 in drivers...
Actually, Mike has his answer as there is a T-TQWT design that uses two 15" woofers and tuned to 8.5 Hz. Loaded in a corner it is over 110dB at 67 watts so 2 of them should hit 120dB with a basic 100 x 2 amplifier in a corner.
http://www.diyaudio.com/forums/subw...ic-subwoofer-digital-organ-2.html#post2884448
The latest exercise in madness is to make the most noise possible for $50 in drivers...
see if this link works: MCM Audio Select 15" Woofer with Poly Cone and Rubber Surround 200W RMS at 8ohm | 55-2974 (552974) | MCM Audio Select
should be a 15" woofer for $15.
should be a 15" woofer for $15.
The snag with the 5 dollar woofer is the high Vas. If you use about 3 cubic feet per driver you get a box resonance of 66Hz and a Q of 1 to get a classical flat tuning you need 7 CF per driver to get a Q of 0.7 and resonance at 47 Hz. 1-2 CF will get you a fat peak at 80-100 Hz but then it will drop of a lot below that.
Have you tried second hand 15" PA drivers?
Have you tried second hand 15" PA drivers?
Hi DrBoar,
7ft^3 per box is only beneficial in this application in that it would reduce power requirements to achieve Xmax in the subsonic range to ~3W per driver. Past that, alignment, flatness, "humps" are irrelevant to the intended scope, purpose, and budget. Cramming more drivers in less space here will make better use of available funds and available amplifier power.
Using cheap plywood (chipboard or OSB or something like that) one could get a ~40-60ft^3 box built (4x4x4' to make best use of sheet size or 2x4x6' as a more floor space friendly option) using 3 sheets and about 10 2x4" x 8' studs. A box of screws and glue puts the budget for this box around $50-60.
We could opt to spend $100 on drivers, and put all 20 drivers in this box (2-3ft^3 per driver), or we could spend another $50 and build a second box, and instead only have funds remaining for an equal budget for 10 drivers, or 5 per box.
Option A makes good use of available amplifier, achieving Xmax at ~145W and 91dB at 8hz.
Option B makes poor use of available amplifier power and takes up twice as much floor space, achieving Xmax at 20W and 86dB at 8hz.
Option A is the clear winner for this application. More woofers, less box, more output, use more available amplifier power and loose half as much living space. Half as much labor also.
Eric
7ft^3 per box is only beneficial in this application in that it would reduce power requirements to achieve Xmax in the subsonic range to ~3W per driver. Past that, alignment, flatness, "humps" are irrelevant to the intended scope, purpose, and budget. Cramming more drivers in less space here will make better use of available funds and available amplifier power.
Using cheap plywood (chipboard or OSB or something like that) one could get a ~40-60ft^3 box built (4x4x4' to make best use of sheet size or 2x4x6' as a more floor space friendly option) using 3 sheets and about 10 2x4" x 8' studs. A box of screws and glue puts the budget for this box around $50-60.
We could opt to spend $100 on drivers, and put all 20 drivers in this box (2-3ft^3 per driver), or we could spend another $50 and build a second box, and instead only have funds remaining for an equal budget for 10 drivers, or 5 per box.
Option A makes good use of available amplifier, achieving Xmax at ~145W and 91dB at 8hz.
Option B makes poor use of available amplifier power and takes up twice as much floor space, achieving Xmax at 20W and 86dB at 8hz.
Option A is the clear winner for this application. More woofers, less box, more output, use more available amplifier power and loose half as much living space. Half as much labor also.
Eric
Last edited:
inappropriate image deleted
I use my speakers not for reproduction but for output on a digital organ and bass gtar. I need to build some low end but for cheap. Traditionally organs can go down to 16hz or 8hz.
Garbage hifi speakers, which cost a billion, can't handle even 30hz. I need some big *** booty bass for a cheap price, can you help me in this build. The goal is to feel the bass from the organ or midi distorted bass gtar.
And not blow anything out, so protection is needed for the hifis I allready have too.
inappropriate image deleted
I've got a ten hertz tapped horn here, but I don't even notice that it's on when I play music. I only notice it running when I listen to movies. (Movies have a TON of low frequency effects.)
Of all the subs I've built, the one that I find most satisfying on music is my TH-Mini clone. It has an F3 of about 40hz, but gets louder than a sealed box of comparable volume. A vented box would go as low, but the TH has better group delay, which makes transients sound better.
IMHO, I wouldn't stress out about doing 20hz if you're listening to music. There just ain't much there.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.