Specific box design questions

[jag]

After reading this this thread, I picked up a pair of tang band W3-594S full range speakers for my first ever diy. Specifications: Power Handling: 15 watts RMS/30 watts max * Voice coil diameter: 3/4" * Nominal Impedance: 8 ohms * Re: 6.6 ohms * Frequency range: 100-20,000 Hz * Fs: 100 Hz * SPL: 87 dB 1W/1m * Vas: .06 cu.ft. * Qms: 6.59 * Qes: .71 * Qts: .64 * Xmax .4 mm * Dimensions: A: 3-3/16", B: 3-1/16", C: 2-1/4", D: 2-5/8"

Subsequently I decided to make a vented wood box instead of small cube (I read Martin King's articles on Transmission Lines, but I think it is going to take some more time before I understand them and start using them for designing TLs).

Since I do not have a table saw, I am planning to use standard 2X4 and 2X6 wood planks available in HomeDepot. With internal width of 3.5" and depth of 2.5" (as show in the picture), the required height is 55" to acheive 8L volume for -3dB at 55Hz (as calculated by WinISD.

My question: Is such an abnormally large H in comparison to W and D going to create problems with the box response?

[Bill Fitzpatrick]

What are you expecting out of this dinky speaker when used full range? One decent bass note at a reasonable volume and the cone is going to fly right out of the cabinet, if it hasn't gone up in smoke first.

You need a more ambitious project unless you are making a table radio.

[jag]

One decent bass note at a reasonable volume and the cone is going to fly right out of the cabinet, if it hasn't gone up in smoke first.

Well I guess I will stick to small cube then, but this is where I got the idea from.

[JohnR]

Well, the thread you reference is for a different driver, a 4". I used a 3.5L vented box for a w3-881s, which is not the same driver but similar. You may like to consider finding some 1/4" material, such as "hobby boards" or oak finishing panels.

Good luck!

JohnR

[planet10]

Bill sure is cranky to-nite.

What he is saying (i interperet) in his sarcastic tone is that these are limited in excursion. A reflex box will unload the speaker below the box tuning and you could be putting a lot more stress on the driver.

I'd go with a 6-8 litre sealed box and plan on adding a subwoofer if you need more bottom. They will never play really loud, but should have quite a nice seemless midrange.

The long length will resonate. If you add a port you will be making a mass-loaded straight pipe.

With their highish Q you could also use them in an open-baffle if you could limit the amount of LF they were exposed to.

dave

[jag]

Bill sure is cranky to-nite.

I guess so, I have been following some of that religion going on at S vs O thread. I have very modest expectations from this effort - I am not expecting any bass or high SPL, if I can get good imaging and clear midrange I will be happy . And if I can learn something on the way that would be great! (It is amazing how much I have learnt already since I started reading these threads). I have to accept though that I did not realize that a modest driver can be damaged by putting it in a over spec'ed reflex box, and that was definitely a very good point brought home.

So, it looks like I have only 2 options: sealed box or open baffle.

The long length will resonate.

That was my concern too. If I do go with a 8L sealed box (3.5"X2.5"X55") then the resonant frequency is: 230Hz (for 1 wavelength) or 460Hz (for 2 wavelengths). Does it mean that I will get bumps at 230 and 460Hz. Can that be avoided by adding damping to both ends?

With their highish Q you could also use them in an open-baffle if you could limit the amount of LF they were exposed to.

The open baffle option looks more interesting as it gives me something new to learn and experiment with. Can you pl provide me with a link to some resource where I can learn about that? Thanks.

[planet10]

Linkwitz
Single Driver Site

that should get you started and give you some ideas.

dave