Couple Questions on PR setups

[Blackout67]

Been thinking long and hard about how exactly I'm going to do my setup in my Mustang. I wanted to try something new and go with a PR system.

Main goals for the system is cheap and efficient as possible with low tuning and conservation of trunk space as priorities.

Passives I was looking at were the Earthquake SLAPS M series 10 and 12 inches. I've heard that they have the best price to value performance compared to other PRs due to their spiderless design making them very efficient with a low FS.
I was also looking at their Tremor 10 inch series to pair with them, for 2 actives and 2 passives. I had sent an email to them but they never got back to me and WINIsd was giving me errors any time I tried to use the PR to model (yes I made sure the units for measurements were accurate and all that)

If anyone could help me with these questions I would greatly appreciate it:
1. The price difference between the 10 and 12 inch is only $10. I'd prefer to spend less money but if the gains from the 12 inch PR are good enough, it won't bother me. Trying for 1-1.25 cubes per subwoofer and radiator set tuned to 30ish hz. I've heard the more displacement you have in I've drivers makes the output flatter. Is this true? I'd prefer it to be as flat as possible as Mustangs tiny airspace making cabin gain frequency decently high

2. What effect, if any does the side of the box that the PR or Subwoofer will be on have? Would it behave like a port where you'd need to have it close to the back trunk wall? Could I have the actives on the right and left side of the box with the PRs firing into the cabin sealed off from the trunk?

3. How should i set my subsonic filter? I know PRs behave more like a ported closure and unload below Fb, but is it a steeper sloap or more gradual? What kind of output should i expect below what i tuned the PR to?

Thanks!

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[Jimi77 Premium Member]

1) I'd go for 12s to maximize displacement from the PR.
2) Not sure how the hatch will interact with the enclosure.
3) PRs have a steeper drop off, so you need to set the SSF even tighter than ported enclosures.

 

[Buck 5,000+ posts]

Just a note- it's really easy to overdrive pr's, like with modern power levels, so keep that in mind. Because of the way boxes work there's going to be a ton of pressure trying to radiate out of those ports/PR's. Idk I didn't see the subs if you listed it, but wattage matters quite a bit, like if you have high powered woofers you might need multiple PR's per woofer. It's not always a 1 to 1 cone area situation. I've designed a bunch but not with PR's at all, but saying what I've seen and heard about.

Never split up the airspace's between port/PR and subs. The subs and whatever radiator should always fire into the same airspace of the car or else you can get cancellation because separate parts of the car can act like boxes themselves.

 

[Blackout67]

1) I'd go for 12s to maximize displacement from the PR.
2) Not sure how the hatch will interact with the enclosure.
3) PRs have a steeper drop off, so you need to set the SSF even tighter than ported enclosures.

What the general rule of thumb for setting the SSF on PR setup? IIRC ported is 1/2 below port tuning. Havnt had to worry about SSF in a while. Sealed its always off for me

 

[Blackout67]

Just a note- it's really easy to overdrive pr's, like with modern power levels, so keep that in mind. Because of the way boxes work there's going to be a ton of pressure trying to radiate out of those ports/PR's. Idk I didn't see the subs if you listed it, but wattage matters quite a bit, like if you have high powered woofers you might need multiple PR's per woofer. It's not always a 1 to 1 cone area situation. I've designed a bunch but not with PR's at all, but saying what I've seen and heard about.

Never split up the airspace's between port/PR and subs. The subs and whatever radiator should always fire into the same airspace of the car or else you can get cancellation because separate parts of the car can act like boxes themselves.

Sub would be the Earthquake Tremor series. They are rated for 300-400 watts rms IIRC. From what I see they have a very low FS compared to the typical 10 inch sub. Idk how accurate it is, but the one way excursion rating is 1.2 inches. The SLAPS M10 shows a one way excursion of 2 inches

Also so I couldnt have a box with the 2 PRs on the side facing the trunk lid and one active on either side of that cabinet? They have to be on the same side? Idk if I would have the length to go with that. Even if its 2 10 inch PRs and 2 10 inch actives, thats gonna be like 44-46 inches in length. Are there any other good 10 inch subwoofers in the ~$200 range that are also efficient? I could make a single active 10 with 2 10inch PRs fit.

I have a JP13 amp to play with and im not planning on doing a alt upgrade, just one big AGM and a big 3 kit so im looking for efficiency but regular ported boxes get a big too big when I model them. My JP13 does ~1300 watts RMS at 2 ohms with 90 percent efficiency

 

[Buck 5,000+ posts]

Sub would be the Earthquake Tremor series. They are rated for 300-400 watts rms IIRC. From what I see they have a very low FS compared to the typical 10 inch sub. Idk how accurate it is, but the one way excursion rating is 1.2 inches. The SLAPS M10 shows a one way excursion of 2 inches

Also so I couldnt have a box with the 2 PRs on the side facing the trunk lid and one active on either side of that cabinet? They have to be on the same side? Idk if I would have the length to go with that. Even if its 2 10 inch PRs and 2 10 inch actives, thats gonna be like 44-46 inches in length. Are there any other good 10 inch subwoofers in the ~$200 range that are also efficient? I could make a single active 10 with 2 10inch PRs fit.

I have a JP13 amp to play with and im not planning on doing a alt upgrade, just one big AGM and a big 3 kit so im looking for efficiency but regular ported boxes get a big too big when I model them. My JP13 does ~1300 watts RMS at 2 ohms with 90 percent efficiency

They don't have to be on the same side, no, but you want it all within the trunk. Like, you don't want to try to fire anything directly into the cabin you just want your stuff to pressurize everything in the trunk, is what I mean. If it's all in phase it's just omnidirectional pressure waves, it works. Just as long as all the waves from the box are exiting into the same airspace, like your trunk. Those aren't high powered woofers with what I mean so you may be fine with 1 to 1 cone area Xmax ratio type deal. It's hard to say without designing it completely.

 

[Jimi77 Premium Member]

What the general rule of thumb for setting the SSF on PR setup? IIRC ported is 1/2 below port tuning. Havnt had to worry about SSF in a while. Sealed its always off for me

I don't know if there is general rule of thumb, just tighter than a ported ssf.

 

[Blackout67]

They don't have to be on the same side, no, but you want it all within the trunk. Like, you don't want to try to fire anything directly into the cabin you just want your stuff to pressurize everything in the trunk, is what I mean. If it's all in phase it's just omnidirectional pressure waves, it works. Just as long as all the waves from the box are exiting into the same airspace, like your trunk. Those aren't high powered woofers with what I mean so you may be fine with 1 to 1 cone area Xmax ratio type deal. It's hard to say without designing it completely.

Yea i know :/ I wish WINISD would work or earthquake would reply to my email

 

[spokey9 5,000+ posts]

Yea i know :/ I wish WINISD would work or earthquake would reply to my email

Earthquake is terrible at responding to technical questions...

 

[Blackout67]

Earthquake is terrible at responding to technical questions...

Thats kind of worrying. What is there customer support like in case of driver defects? Hopefully the RMA process would not be miserable

 

[spokey9 5,000+ posts]

Thats kind of worrying. What is there customer support like in case of driver defects? Hopefully the RMA process would not be miserable

I don't know about returns. I wanted some of the tremor 15's a few years back but I couldn't reach anyone to ask about t/s specs since the fs on all their subs seem rated too low imo.

 

[Blackout67]

I don't know about returns. I wanted some of the tremor 15's a few years back but I couldn't reach anyone to ask about t/s specs since the fs on all their subs seem rated too low imo.

Maybe thats why I was having issues modeling in WINIsd. It only had the problem. with the PR and not any other alignments and a lot of their description is the typical car audio jargon but the way i saw it was it makes sense the FS would be low since there is no spider suspension to stiffen up the cone movement, just high roll foam on either side of the cone so it made sense in my mind atleast that it would be pretty compliant and have a low FS

Either way those the results speak for themselves and it seems to be pretty popular and people get good response out of them regardless of if the TS specs are off. They seem to get much better reviews than thr Dayton passive drivers I was looking at

 

[spokey9 5,000+ posts]

Maybe thats why I was having issues modeling in WINIsd. It only had the problem. with the PR and not any other alignments and a lot of their description is the typical car audio jargon but the way i saw it was it makes sense the FS would be low since there is no spider suspension to stiffen up the cone movement, just high roll foam on either side of the cone so it made sense in my mind atleast that it would be pretty compliant and have a low FS

I don't think earthquake is putting out legit specs.

Have you bought everything yet?

Parts express has dayton subs and pros that ain't hard on the wallet...plus top notch tech help and customer service

 

[Blackout67]

I don't think earthquake is putting out legit specs.

Have you bought everything yet?

No not yet. Don't have the money quite yet and I want to plan things out instead of impulse buying while I'm stoned after work like usual

 

[spokey9 5,000+ posts]

No not yet. Don't have the money quite yet and I want to plan things out instead of impulse buying while I'm stoned after work like usual

Parts express buddy...see if they got what you need. The specs on the dayton stuff are legit and a 5 year warranty behind them