4th order folks, tell me if I am on track!

[Jroo 10+ year member]

here are the specs for my 2 old 10's.

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%

Here is what I have box related.

My max H is 13 inches, width is 16 inches, and lenght is 38 inches

Sealed side is .936

Ported side is 2.042

Port is 55 square inches tuned to 55hz.

Trying to play music from 70 down and be musical. Not worried about metering at all. Will be giving the pair a true 800rms from an old Rockford 800 A2. What do you think so far?

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[pro-rabbit 5,000+ posts]

I would bring your tuning down some for a daily setup maybe 45-50

I can not comment on the specs though as I'm on my phone and I don't feel like doing math in my head..far to early for that.

 

[Jroo 10+ year member]

I had a feeling the tuing was too high. If I brought the tuning down, I would have no issues playing 70 down? I would like it to play flat if possible.

 

[pro-rabbit 5,000+ posts]

I had a feeling the tuing was too high. If I brought the tuning down, I would have no issues playing 70 down? I would like it to play flat if possible.

If you want more control then I would suggest a 6th order which will typically have a more "smooth" response curve. A 4th order by nature will have a decently sized peak.

 

[Jroo 10+ year member]

i was told a few times these woofers would do very well in a 4th order. What are people looking at to say that they are 4th or 6th order. My 4th could have a peak as long as it down lower.

 

[i2ain2thunder 10+ year member]

yeah I'd tune that lower I always like lower tuned ports. Higher tuned ones just don't give the bass enough depth to me.

 

[surreal 10+ year member]

Firstly and importantly, what vehicle is it being placed in, and where? This will have a big effect on cabin gain which youll need to get an idea for to shape the response of the enclosure.

 

[Jroo 10+ year member]

going in the hatch area of a Pathfinder.

 

[Jroo 10+ year member]

another question. Does port up or back matter with bandpass, like it does with ported. I was just going to do port up.

 

[Jroo 10+ year member]

any thoughts?

 

[Flastrongman 10+ year member]

I'd go bigger on the sealed section and smaller on the ported because of the weak motors on those subs you'll have almost no lows with the specs you listed.

 

[Jroo 10+ year member]

how much would the Fs play on going low. These subs are basically the credence build house no named solobarics. When I called on them, they said think the old round solobaric with a generic label on them. I would agree that compared to newer subs, these dont have the motor that is out there now. So a larger sealed vs smaller ported aids in how low a bandpass will play?

 

[Jroo 10+ year member]

Ok, so I played with a few online calculators and took the average of what they all said. Each gave me something differernt.

Sealed side 1.17

Ported side 0.57

Tuning Frequency 43.87

They are saying this will play roughly 76 Hz to 25 Hz. These are looking more like the recommendations that Flastrongman said by going way larger on the sealed side and smaller on the ported. I also figure I will keep the port around my original 55 square inches. What do you think now?

 

[Flastrongman 10+ year member]

that's too small now. just do a 1:1 ratio if you want them to have a good freq response. 1.5 sealed/1.5 ported tuned to around 50hz

 

[Buck 5,000+ posts]

Is it just me or does these parameters steer more towards a 6th order than a 4th?