subsonic filtering

[LongThrow]

I have a Rockford fosgate R1 r1s410

Atrend 10 inch 1.25 cf tuned to 37 hz.

Sub is rated 150w RMS svc4ohm. Freq 24-250 SPL 86. There are no given minimum or optimum specs for a ported box. Only given specs are .75 cf sealed box.

That all being said, what should I set my subsonic filter to?

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[Sundownhoe]

27.5 subsonic

 

[Louisiana_CRX 5,000+ posts]

I have a Rockford fosgate R1 r1s410
Atrend 10 inch 1.25 cf tuned to 37 hz.

Sub is rated 150w RMS svc4ohm. Freq 24-250 SPL 86. There are no given minimum or optimum specs for a ported box. Only given specs are .75 cf sealed box.

That all being said, what should I set my subsonic filter to?

Since thats a basic sub and not designed to play but down to 24hz Id set the subsonic at 35hz...it will have a slow roll off below that set frequency ...but should help prevent damage to your sub from the lower frequencies

 

[LongThrow]

I have a basic understanding of what a SS filter is for. To prevent damaging over excursion. I googled a bit more after posting this topic (wanted to see what caraudio.com had to say instead of yahoo answers ) and the formula is to take the tuned freq of your box and divided by 2. Then divide by 2 again. That number is then subtracted from your boxes tuning and should set your filter accordingly.

The first responder stated somewhere around 27 hertz. Which is what I got from my calculations. What would be the difference in setting it at 25 and then at 35? Just a more prominent roll off at a higher freq? How would this effect (or affect? Didn't pay much attention in school) my SQ or SPL?

 

[Louisiana_CRX 5,000+ posts]

I have a basic understanding of what a SS filter is for. To prevent damaging over excursion. I googled a bit more after posting this topic (wanted to see what caraudio.com had to say instead of yahoo answers ) and the formula is to take the tuned freq of your box and divided by 2. Then divide by 2 again. That number is then subtracted from your boxes tuning and should set your filter accordingly.
The first responder stated somewhere around 27 hertz. Which is what I got from my calculations. What would be the difference in setting it at 25 and then at 35? Just a more prominent roll off at a higher freq? How would this effect (or affect? Didn't pay much attention in school) my SQ or SPL?

What is the port length on the atrend box ?

 

[Louisiana_CRX 5,000+ posts]

If a higher end sub Id sugested going lower on the subsonic filter...but like I said that is their basic model it should sound good but isnt built to take the abuse like better quality subs

 

[LongThrow]

Width 16.25

Depth 15.5

Height 12

Vent Width 1.25

Vent Height 10.5

Vent Length 22

Vent Dim 13.13

Hz (Tuning Frequency) 37

Gross Cu. Ft. 1.25

Net Cu. Ft. 1

Box specs

 

[Jeffdachef 5,000+ posts]

I have a basic understanding of what a SS filter is for. To prevent damaging over excursion. I googled a bit more after posting this topic (wanted to see what caraudio.com had to say instead of yahoo answers ) and the formula is to take the tuned freq of your box and divided by 2. Then divide by 2 again. That number is then subtracted from your boxes tuning and should set your filter accordingly.
The first responder stated somewhere around 27 hertz. Which is what I got from my calculations. What would be the difference in setting it at 25 and then at 35? Just a more prominent roll off at a higher freq? How would this effect (or affect? Didn't pay much attention in school) my SQ or SPL?

multiply your tuning by .75 to keep it simple man.

 

[Louisiana_CRX 5,000+ posts]

Width 16.25Depth 15.5

Height 12

Vent Width 1.25

Vent Height 10.5

Vent Length 22

Vent Dim 13.13

Hz (Tuning Frequency) 37

Gross Cu. Ft. 1.25

Net Cu. Ft. 1

Box specs

That looks about right spec wise...35 may be to high ...but id probably start off about 30...and listen for any poping or weird sounds in the sub...if it sounds good you should be safe

 

[LongThrow]

Thanks again! This forum and its members are life savers!

 

[Louisiana_CRX 5,000+ posts]

Thanks again! This forum and its members are life savers!

this is the best car audio forum on the net currently ...

 

[LongThrow]

That's why I'm here. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif best place to learn IMO past bcae.

 

[hispls 5,000+ posts]

You'll have a hard time breaking the woofer from setting HPF too high, on the other hand, a woofer designed for low power may not survive bottoming out even once!

Safest thing to do would be to start your HPF right at box tuning and watch the woofer through a variety of music at the loudest levels you'll use. Then you can gradually lower it if you need. Be cautious unless you can afford to and like repairing woofers, because the lower frequency you go the more the cone wants to move and even more so after you dip below tuning.

Also if you mentioned what amp you're using I didn't catch that. Damaging a woofer from over-excursion is largely dependent on power. For example if the sub is rated 250W you'll likely never kill it with 50W no matter where you set HPF, but if you're playing close to or even above rated power you'll need to be much more attentive to what the woofer does.

 

[LongThrow]

Using a PLANET AUDIO PX1500M. I know these are highly overrated. It has a 30amp fuse so it can't do more than 300watts at 4 ohms. It says it does 450 at 4 but I know that's a terrible lie. What would you say how much RMS watts this puts out?

 

[LosIsATool 5,000+ posts]

75 at 4ohm