tempest & Sub-P2 Kit (1 Viewer)

[KurtJ]

I'm new to this DIY stuff, but am looking to build a subwoofer based on the Tempest & Sub-P2 kit with the AVA 250 amp. My HT is approx. 2288 ft^3; 16*13 ft^2 with one wall 8 ft and the other 16 ft high.

Where can I find enclosure plans on Adire's web site? Have looked but couldn't find it. Do I need to email the company & ask?

Also, will be mating it to some Polk satellites with the following Freq. resp: 100-22KHz, but -3dB of 140-19KHz.

Any help will be appreciated.

Kurt

 

[Dustin B]

http://www.adireaudio.com/tech_papers/tempest_apps.htm

 

[KurtJ]

Thanks for the help with those designs. Now I'm even more confused as ever( well, just confused).

I do not understand the language of speaker building when it comes to Fs, Fc, BL, Vas, Q, Qms, Qes, Qts, Rms, Re, Mms, Cms,EPB, & tuning frequency.

Is there a website or link here to help me understand? Why do you add mass to a passive radiator?

Thank You

Kurt

 

[Kyle Richardson]

Kurt,
If you are building just a kit then you really wont need to know all of those definitions because the driver, enclosure and tuning has all been designed for you. Now, if you are going to build from scratch then you definitely need to know those definitions and I recommend a book called "The Loudspeaker Cookbook" available at Amazon or Parts Express.
You add mass to a PR to change the tuning frequency of the enclosure.

 

[KurtJ]

I have looked at the LpsCAD software and models of the sealed, vented, and PR designs. I thought at first I was going with a PR design. Those graphs are confusing to me. Which of the designs actually gives or can give the lowest freq reponse. I'm dying to hear a 16Hz organ tone. which of the three variations of each should I go with.

Thanks,

Kurt

 

[Jack Gilvey]

Vented and PR produce almost identical alignments and will get go lower than sealed, although they're bigger. With Tempest, I'd just go vented. For really deep bass, go EBS, tuned to 15.8Hz. From the vented Tempest apps page:

The EBS design for Tempest is a traditional extended bass response alignment. This alignment provides deep bass extension at the expense of maximum SPL
capability. It provides anechoic extension to the mid teens, and due to the roll- off well below 20 Hz maintains an accurate sonic character. Overall, the sonic
character of this alignment is of neutral, natural bass (thanks to a group delay of less than 20 ms at 20 Hz), with very good extension and SPL capability. This
alignment excels at reproduction of acoustic bass signals (such as from acoustic string basses, cellos, tympanis, and especially pipe organs).

 

[KurtJ]

WAF issues are keeping me from the tall cabinet needed for the EBS PR on the Adire web site. Can I modify the dimensions as long as the volume remains constant? Or what problems will I encounter and need to overcome?

 

[Anthony_Gomez]

Kurt, as long as you:
1)keep the internal volume the same
2)use adiquate bracing
3)keep the pair of PR's on opposite parallel walls (to cancel the forces)
...then you will be fine

 

[KurtJ]

Modifying the volume is becoming quite a mathematical chore. I have calculated original EBS internal volume minus PRs, driver, and holes in the supports.

I have also done the same for the modified cabinet I am planning. However, I have noticed that the dimensions of my modified cabinet (approx 29.375 inches for each L, W, and H) are similar to the SBB4 alignmnet on Adire's web site.

How much low end will I lose if I decide to go with that design versus the EBS alignment I am trying to modify? I really want to feel the 16-20 Hz organ pedal tones.

Thanks for the help.