Ported enclosure questions

[pimpnyou204 10+ year member]

I love car audio so I constantly read into things and I have a few questions on some things of what I read and I know some may be repetitive so a simple yes no or true false would suffice and anything else you'd like to add would be very beneficial.

Sub/port on same side of box would a L slot port that goes behind 1 of the motors hinder the sound in the port?

If slot area is generally 12-16 is aero really slightly less with 8-12 per cube?

If tuning high 40+ u go with 16 per cube 30-40hz about 14 and 12 per cube if below 30?

For spl burps you can go in the upwards of 18-20 per cube?

How exactly does tuning above/below and building a box above recommended ts specs affect the overal sound?

Kind of a broad question but.. How is box size relevant to tuning? Big box for tuning low and small box for high tuning..

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[Buck 5,000+ posts]

Sub/port on same side of box would a L slot port that goes behind 1 of the motors hinder the sound in the port? Not really ***edit, I usually like to not have this happen though.

If slot area is generally 12-16 is aero really slightly less with 8-12 per cube? Yes, but both of these rules of thumb aren't always accurate.

If tuning high 40+ u go with 16 per cube 30-40hz about 14 and 12 per cube if below 30? No.

For spl burps you can go in the upwards of 18-20 per cube? Yes, but testing > theory for SPL.

How exactly does tuning above/below and building a box above recommended ts specs affect the overal sound? What?

Kind of a broad question but.. How is box size relevant to tuning? Big box for tuning low and small box for high tuning.. You can tune a box to any frequency, no matter what size. Large box tuned low tends to have a flatter response. Smaller boxes tuned higher tend to have a peakier response. I like tuning low for daily.

 

[Kangaroux 5,000+ posts]

to elaborate on port area vs. tuning...the lower a frequency the more air it will move. therefore, it would make sense to have more port area to let the air flow freely on a low tuned setup rather than a high tuned setup. not to say you can't have a large amount of port area if youre tuned mid 40's, but it just makes more sense to use that in a lower tuned box

 

[RAM_Designs 5,000+ posts]

to elaborate on port area vs. tuning...the lower a frequency the more air it will move. therefore, it would make sense to have more port area to let the air flow freely on a low tuned setup rather than a high tuned setup. not to say you can't have a large amount of port area if youre tuned mid 40's, but it just makes more sense to use that in a lower tuned box

Actually, for a given excursion you're going to have air moving more rapidly in and out of the port with a higher tuning(makes sense, more cycles per second vs a lower frequency). So theoretically, given the same excursion you'd need less port with a lower tuning in order to avoid port noise. The issue is that with a lower tuning, like 28-30hz, it's easier to hear port noise or vehicle vibrations since that upper 20's to low 30's range(which is where the port will be working the hardest) is where sound starts to go from being audible towards more of a feeling experience.

I do understand your point with a sub moving easier at a lower frequency, but around the tuning frequency the sub won't be moving that much anyways.

 

[pimpnyou204 10+ year member]

I mean like if said sub suggested a box be 2-4 cubes and I decided I wanted to get deep lows I'd go with a 4.5 cube box. Would that just be stupid bcuz the box would be too large for the subs to be able to move that much air in the box?

If they suggest a 30-34 hz tuning and u like 36 how is u tunin to that frequency going to change that sound? I guess what I'm saying is tuning far from the speakers fs going go effect the SQ or roll off of the sub

 

[Buck 5,000+ posts]

I mean like if said sub suggested a box be 2-4 cubes and I decided I wanted to get deep lows I'd go with a 4.5 cube box. Would that just be stupid bcuz the box would be too large for the subs to be able to move that much air in the box?
If they suggest a 30-34 hz tuning and u like 36 how is u tunin to that frequency going to change that sound? I guess what I'm saying is tuning far from the speakers fs going go effect the SQ or roll off of the sub

It really depends. Give us specifics.

 

[RAM_Designs 5,000+ posts]

I mean like if said sub suggested a box be 2-4 cubes and I decided I wanted to get deep lows I'd go with a 4.5 cube box. Would that just be stupid bcuz the box would be too large for the subs to be able to move that much air in the box?
If they suggest a 30-34 hz tuning and u like 36 how is u tunin to that frequency going to change that sound? I guess what I'm saying is tuning far from the speakers fs going go effect the SQ or roll off of the sub

Box volume and tuning is going to affect your frequency response. Up the tuning and you get more output, but lose some of your low-end output that you'd have with a lower tuning. Tune low and it's the opposite, you sacrifice loudness in the upper frequency range to be able to reproduce the lower frequencies well.

 

[pimpnyou204 10+ year member]

Actually, for a given excursion you're going to have air moving more rapidly in and out of the port with a higher tuning(makes sense, more cycles per second vs a lower frequency). So theoretically, given the same excursion you'd need less port with a lower tuning in order to avoid port noise. The issue is that with a lower tuning, like 28-30hz, it's easier to hear port noise or vehicle vibrations since that upper 20's to low 30's range(which is where the port will be working the hardest) is where sound starts to go from being audible towards more of a feeling experience.

I do understand your point with a sub moving easier at a lower frequency, but around the tuning frequency the sub won't be moving that much anyways.

Makes sense but only thing I'm not understanding about thatis why do u tune low for a hair trick (more air movement) if a higher tune will displace more air at a fast rate?

 

[RAM_Designs 5,000+ posts]

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[pimpnyou204 10+ year member]

It really depends. Give us specifics.

Example:

AQ says to tune 37-40 I'm assuming that's bcuz the natural fs is 41 right? Bcuz they say to tune it at that spot does it mean it will have it's highest peak at that spot if u were to build a box to each frequency? (assuming there was no resonant frequency being involved in a car)

 

[Buck 5,000+ posts]

It would be loudest at if you tuned the enclosure to the subs Fs, I believe. But that's all it is. There are so many other factors.

 

[Slo_Ride 5,000+ posts]

I try not to have the port to close to the sub. I've had problems with the sub unloading if it is to close to the port resulting in mechanical failure.

 

[pimpnyou204 10+ year member]

Box volume and tuning is going to affect your frequency response. Up the tuning and you get more output, but lose some of your low-end output that you'd have with a lower tuning. Tune low and it's the opposite, you sacrifice loudness in the upper frequency range to be able to reproduce the lower frequencies well.

Well we know the higher the frequency the more loud to our ears it gets (playable by subs.) for the ppl who tuned real lowish (27ish) , to our ears would that give a more flat response bcuz it would peak low and flatline around 33 and even out the low notes we hear faintly and bring them to the same level a 45hz note plays?

 

[Buck 5,000+ posts]

I try not to have the port to close to the sub. I've had problems with the sub unloading if it is to close to the port resulting in mechanical failure.

This is true.

 

[pimpnyou204 10+ year member]

edit

Lol wow I asked aquestion ram doesn't know I'm kinda shocked! But in all serious though aren't most spl comps won at higher frequencies is that bcuz their resonant frequency in the car is that high? If not my thought would be if low tuning is related to more air disruption then that would give u more pressure (spl.) much like a hurricane or tornado when they come by the pressure is much higher. I dont know maybe over analyzing at this point...