My class needs your help!

[plyhammer]

I know this is a double post but I only have a week to calculate this:

I am a teacher of a middle school and my students each have been given a speaker to design a box for. They are in the middle of learning terminology right now and I am trying to work out something to help them out in the design of their enclosure. Anyway, I need to find out what the appropriate volume should be for an individual speaker. The second stage of the project is for a few of the students that normally struggle in the class and will be given a chance to do something constructive. They will take 128 speakers and wire them to 1 ohm and we need to find the box size for maximum spl. We will be putting this into a vehicle and actually taking it to a comp or two. We don't expect to win anything but thought it would be a good motivator. Anyway, here are the specs of the speakers.
thanks all

4" extended range drivers
Driver features: 3/4" V.C. on paper former, large flat spider, paper cone, rubber surround, and a paper dustcap.
Specifications: *Power Handling: 5 watts RMS/10 watts max *VCdia: 3/4" *Le: .60 mH *Znom: 8 ohms *Re: 7.50 ohms *Frequency range: 75-15,000 Hz *Fs: 105 Hz *SPL: 86 dB 2.83V/1m *Vas: .08 cu. ft. *Qms: 5.0 *Qes: .90 *Qts: .76 *Xmax: 1 mm *Driver Dimensions: Overall Diameter: 4", Cutout Diameter: 3-11/16", Mounting Depth: 2-1/4".

[GCAdidas13]

I know this is a double post but I only have a week to calculate this:

I am a teacher of a middle school and my students each have been given a speaker to design a box for. They are in the middle of learning terminology right now and I am trying to work out something to help them out in the design of their enclosure. Anyway, I need to find out what the appropriate volume should be for an individual speaker. The second stage of the project is for a few of the students that normally struggle in the class and will be given a chance to do something constructive. They will take 128 speakers and wire them to 1 ohm and we need to find the box size for maximum spl. We will be putting this into a vehicle and actually taking it to a comp or two. We don't expect to win anything but thought it would be a good motivator. Anyway, here are the specs of the speakers.
thanks all

4" extended range drivers
Driver features: 3/4" V.C. on paper former, large flat spider, paper cone, rubber surround, and a paper dustcap.
Specifications: *Power Handling: 5 watts RMS/10 watts max *VCdia: 3/4" *Le: .60 mH *Znom: 8 ohms *Re: 7.50 ohms *Frequency range: 75-15,000 Hz *Fs: 105 Hz *SPL: 86 dB 2.83V/1m *Vas: .08 cu. ft. *Qms: 5.0 *Qes: .90 *Qts: .76 *Xmax: 1 mm *Driver Dimensions: Overall Diameter: 4", Cutout Diameter: 3-11/16", Mounting Depth: 2-1/4".
I have no idea about enclosure size, but... with a frequency range starting at 75hz then what are your plans for SPL competitions?

[plyhammer]

most comps allow 80-100 hz. Since this is what we have to work with this is what we need to do?

[GCAdidas13]

i would just expect for the frequency response aroud 100hz to be diminished by the 75hz cutoff. just an assumption

[plyhammer]

anyone else?

[plyhammer]

Anyone with a guess. My class will be building this box this week. 128 speakers in fake wall. I need a guess on box volume and port space. Best guesses please.

[theCybe]

Which school is this?

[Berry47]

Off topic...

Why weren't my teachers this cool......

[bcarpenterfhl]

i dont have bassbox pro 6 on the computer i'm on, or else i'd do it. but if you enter all those speaker specs into the program, it will suggest a box volume and tuning frequency (that's if you want it ported) for the most output.

[Raven]

4" driver * 128...
Assuming a 3.75" SD you're looking at 11.04 square inches of cone area per speaker. 1413.72 square inches for 128. Attach that to a 1mm p2p excursion and you're looking at 1413.72 X 0.0393700787 = 55.65 cubic inches of linear displacement. :drool: =)

That's a start.

[bcarpenterfhl]

i enetered in all the driver specs in bbp6, and they recommend a 15.95 cubed box, tuned to 108.7 Hz for maximum output.

[jellyfish420]

if you tune that to 109 and try to blast 100hz thru them, with only 1mm p2p you'll probably unload them quite easily...

what happens if you tune to 35 and try to burp 20Hz tones?

[bcarpenterfhl]

he said the frequency range was 75-15,000 Hz.

[jellyfish420]

he said the frequency range was 75-15,000 Hz.




most comps allow 80-100 hz.

if he can play 100Hz being highest... i think the useable frequency range just went to 75Hz-100Hz ;)

[bcarpenterfhl]

well ****, didnt read that part.

[plyhammer]

anyone know about just a box for a single one? anything?