# Bass Speaker Box

#### Jon H

Hi I have a couple of Celestion Pulse 10 bass speakers and looking to build a box for them. The specs on the speakers are Fs 66.3Hz, Qts 0.444 and Vas 1.06 cubic feet (thats for one).
Can anyone tell me if these speakers would be suited to a sealed or ported box. Have a idea of a ported box with a volume of 2.7 cubic feet and Fb of 40Hz and have managed to draw some responce grapths but any opinions would be gratefully received.

#### Galu

Welcome to the forum!

A Qts of 0.444 sits on the cusp between sutability for a vented or sealed enclosure.

https://eminence.com/pages/support__understanding-loudspeaker-data

"Qts of 0.4 or below indicates a transducer well suited to a vented enclosure. Qts between 0.4 and 0.7 indicates suitability for a sealed enclosure. Qts of 0.7 or above indicates suitability for free-air or infinite baffle applications. However, there are exceptions!"

#### GM

Greets!

Either as noted, though need to know how much, if any, added series resistance (Rs) there is since it could raise effective Qts' enough to either go sealed or (ML)TL, then use this math for vented or sealed here.

T/S max flat alignment:

Vented net volume (Vb) (L) = 20*Vas*Qts'^3.3

(Ft^3 = (Vb)/~28.31685)

Vented box tuning (Fb) (Hz) = 0.42*Fs*Qts'^-0.96

F3 (Hz) = Fs*0.28*Qts'^-1.4

(Qts'): (Qts) + any added series resistance (Rs)

#### Jon H

Many thanks for your comments think it will be a vented enclosure, not very familiar with the mathmatical symbols though so cant work out the formulas.

1 user

#### Galu

not very familiar with the mathmatical symbols though

Yes, there's a mixture of unit symbols and quantity symbols in there that I find it easy to sift through, but you may not.

I believe GM is suggesting you take into account any series resistance, due to crossover coils etc., into consideration when deciding the exact Qts figure to use in your calculations.

However, since the discrepancy may be small enough to ignore in your case, perhaps this simple calculator will offer a substitute for the mathematics:

https://www.diyaudioandvideo.com/Calculator/SpeakerBoxEnclosure/

1 user

#### Jon H

Gala and GM thanks very much for your information. The attachments you gave me are very informative and yes the simple calculator will prove a substitute for the mathematics. I believe I can now build my ported enclosure with confidence. Thank you.

1 users