Forgot I had these subs in the attic, what box?

[Jroo 10+ year member]

Wife had me cleaning up the attic and found an old box. I forgot I bought a set of credence clearance subs couple of years back cheap. Credence gave some very general box requirements and specs. Said could go in 0.5 sealed or 1 cube ported, but didnt giving tuning or port size. Looking at the specs, do either of these make sense or would you do something different? I will do a something quick as a project with my 9 year old duing his winter break coming up.

here are the specs Credence gave for the 2 10" subs I have:

Power Rating RMS Cont. 250 Watts

Max Power Rating-Unclipped Amp 350 Watts

Freq Response 25-150 Hz

Nominal Imp 8 Ohms

Voice Coil 2" 4 Layer

FS 25.18 Hz

Qms 8.8040

Qes 0.3579

Qts 0.3439

Vas 67.30 Liters

Cms 0.3994E-03 M/N

Re 6.93Ohms

BL 17.505 Newtons/Amp

Sd 0.034636 Sq. m.

Mms 0.100017 Kg

Hvc 0.980"

Hag 0.375"

Xmax 0.303"

Xlin 0.605"

Ref Eff 0.2885%

Predicted Output 86.802 DB/1W/1M

Power Rating RMS Cont. 250 Watts

Max Power Rating-Unclipped Amp 350 Watts

Freq Response 25-150 Hz

Nominal Imp 8 Ohms

Voice Coil 2" 4 Layer

FS 25.18 Hz

Qms 8.8040

Qes 0.3579

Qts 0.3439

Vas 67.30 Liters

Cms 0.3994E-03 M/N

Re 6.93Ohms

BL 17.505 Newtons/Amp

Sd 0.034636 Sq. m.

Mms 0.100017 Kg

Hvc 0.980"

Hag 0.375"

Xmax 0.303"

Xlin 0.605"

Ref Eff 0.2885%

Predicted Output 86.802 DB/1W/1M

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[akadj 10+ year member]

How old are they? They seem to have similar specs as a old pair of 12" woofers (B-52) i had. The box spec for them was bigger though. .. 1.85 cubes each box with a single 4" port 12" long

 

[Jroo 10+ year member]

they are labeled as Bostwick HD pros. I have heard the same sub was labeled as an Atomic model and I think one other sub. They have been in the attic about 4 years, couldnt tell you how old the sub actually is. I think credence had the either laying around or had parts and built them. I Also have a JL 18w6 from them and I think it was parts they had left as they were a JL build house. They built a bunch but could not put the JL logo on the dust cap.

 

[whazz]

Well, i wouldnt make a closed enclosure.. I think i would do a vented box..

If you do the vented, it would be 39,7L, and two vents with the size og 0.047m in diameter (4.7cm), and a length of 26cm each, im sorry it isnt in inches, and ft3..

This is without me ever listening to the sub, but i plugged it into WinISD, and thats the best i could get out of it..

You could maybe do a 76litres box, with two vents with the size 0,0047m diameter, and 0,181m length.. You will lose a Little overall dB, but it goes a Little deeper..

Theese numbers are 100% taken from WinISD, where i tried some diffrents numbers.. Theese where the one i liked the look of..

 

[Jroo 10+ year member]

Well, i wouldnt make a closed enclosure.. I think i would do a vented box..If you do the vented, it would be 39,7L, and two vents with the size og 0.047m in diameter (4.7cm), and a length of 26cm each, im sorry it isnt in inches, and ft3..

This is without me ever listening to the sub, but i plugged it into WinISD, and thats the best i could get out of it..

You could maybe do a 76litres box, with two vents with the size 0,0047m diameter, and 0,181m length.. You will lose a Little overall dB, but it goes a Little deeper..

Theese numbers are 100% taken from WinISD, where i tried some diffrents numbers.. Theese where the one i liked the look of..

Thanks for modeling, sounds like you modeled sealed and ported? Can you tell me what sealed sizes and responses it came up with?

 

[whazz]

Thanks for modeling, sounds like you modeled sealed and ported? Can you tell me what sealed sizes and responses it came up with?

I actually did both Sealed, ported, and 6th order bandpass.. I prefered the look from the portet..

Ported 1: Tuned to around 30hz -3dB.

Ported 2: Tuned to around 24hz -3dB, but with a +1.5dB gain from 70hzish

Sealed: Tuned to around 50hz -3dB, 30hz is -10dB.. 21Litres net.

6th: This one is kinda funny.. It's tuned to around 23hz, but with +/- 1dB, and all in all there is a Little output with this box.. If we take it from the lowest beside 23hz, and take -3dB from that it's tuned to 20hz, but than u will have -2dB with 1watt.. at 28hz, u will have -1dB with 1 watt..

Front chamber: 10L, 2 ports which is 0.047m*0.249m

Rear chamber: 55L, 2 ports which is 0.047m*0.430m

I would either do ported 2, or 6th order..