Jeep is Back... One SA-15 / 153.5 dB -- Fun times =)

[bhsdriller 10+ year member]

It's not designed to play 29hz....stricly a box for competing, not playing music

Yes, in a way subs are designed to play lower notes but they can still play anything really

Guys that compete in crx's burp at like 61hz

 

[sundownz Pro Seller]

Indeed... it's an SPL box. For an SPL box you play the vehicle resonant peak -- which is 53 Hz for me. If I had a larger vehicle it would be lower. Since the goal is to win the competition with an SPL box naturally it is tuned to where it will do so //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

For the record, though, I've used the same box to bass-race 149.9 with the old "Monster" prototype.

Some time ago I did 156.1 dB with an NS v.2 15" right when they were introduced with 10.3kw of power -- some of the changes I've made on the vehicle since seem to have gained quite a bit of SPL output based on the SA-15 numbers. So... when I get NS v.2 motors in again I will try it again.

 

[manyhobbies 10+ year member]

I am new to all this spl numbers game. But seriously, is'nt bass a low tune? 51+hz is anoying is'nt it even if listing to music at high dbs? If high numbers is what it's all about, would'nt it be better to tune even higher then 51hz? Truelly I am trying to gain some understanding here.

Thanks, Russ

 

[813thumper 10+ year member]

i am new to all this spl numbers game. But seriously, is'nt bass a low tune? 51+hz is anoying is'nt it even if listing to music at high dbs? If high numbers is what it's all about, would'nt it be better to tune even higher then 51hz? Truelly i am trying to gain some understanding here.Thanks, russ

this box is not meant for playing music

 

[Kangaroux 5,000+ posts]

I am new to all this spl numbers game. But seriously, is'nt bass a low tune? 51+hz is anoying is'nt it even if listing to music at high dbs? If high numbers is what it's all about, would'nt it be better to tune even higher then 51hz? Truelly I am trying to gain some understanding here.Thanks, Russ

what thumper said. what you're thinking of would be something like sub-bass, the kind of bass that just sorta shakes stuff. it's much easier for a sub to be loud at a higher frequency i.e. 50Hz. every vehicle acts almost like a ported box, it has some sort of "tuning" to it where it is the loudest. most vehicles this is between 50-60Hz but it can vary. if you can find your vehicle resonant frequency, and then tune a box to that frequency, you can pull off some serious numbers.

 

[05fronty 5,000+ posts]

mine is like 63hz lol.

 

[wickedwitt 10+ year member]

I am new to all this spl numbers game. But seriously, is'nt bass a low tune? 51+hz is anoying is'nt it even if listing to music at high dbs? If high numbers is what it's all about, would'nt it be better to tune even higher then 51hz? Truelly I am trying to gain some understanding here.Thanks, Russ

On an AC meter, yes. On a TL, they are most sensitive at 50-80hz as they are essentially a CO2 sensor. The most change in CO2 pressure occurs in that note range. The old AC meters you could cheat them and actually get a higher note off your mids than you could subs as they were essentially an audible microphone meter.

 

[sundownz Pro Seller]

I am new to all this spl numbers game. But seriously, is'nt bass a low tune? 51+hz is anoying is'nt it even if listing to music at high dbs? If high numbers is what it's all about, would'nt it be better to tune even higher then 51hz? Truelly I am trying to gain some understanding here.Thanks, Russ

The frequency depends on the vehicle. Larger vehicles peak lower and as you go to small vehicles the peak higher -- vehicles the size of or close to the size of my Jeep are usually 50-53 Hz. Larger SUVs can be in the high 30s to low/mid 40s. Very small cars can be in the 60s.

You tune for the vehicle peak for SPL. Small vehicles are preferable within reason for the higher frequency since it requires so much less excursion to achieve a given SPL -- for example... it would take 400% more excursion at 20 Hz than 40 Hz to do the same SPL (4x the excursion for a drop in octave). Obviously if you have a certain number of woofers for a class and they can move only so far and you want the highest numbers possible you want a reasonably high frequency to play -- so small to mid-size vehicles are very popular for competition SPL. Alternatively walling off a vehicle and reducing cabin size that way can also raise the resonant frequency of the cabin; so large vehicles with walls can peak high as well.

If you don't compete in SPL organizations much of this stuff will have no use or meaning to you. As with automobile drag racing... where most folks find a 4000 horse-power vehicle that only goes straight to be useless for their needs but it is designed for that sport and for that application. Asking what my box does at 29 Hz is like asking the 4000 horse-power drag-races how he does on an Indy track //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

For me as product designer it's a great way to test products to see what they can handle as this type of things generates lots of pressure on soft parts, lots of thermal stress and shock on coils, and so forth. Obviously it's not the only thing I do to test products but it certainly helps //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[wickedwitt 10+ year member]

I figured it would be a high hz tone. Wonder what it would do at 29hz? I really think the high base is disturbing to hear at high dbs.Is'nt a subwoofer intended for hz below 51hz? I thought thats what woofers were designed for.

That is a remarkable score none the less. Would like to see some real low bass testing.

Russ

Most are designed for 20-80hz. Most will play ~200hz fairly well. Once you get above that, the large cones of a sub get in the way of producing a tone that high, due to cycling, that's why the smaller the speaker, the higher hz it is designed to play. Full range speakers usually have a sub that plays 20-200/250ish then a mid driver and maybe tweeter that does 200-22k

 

[wickedwitt 10+ year member]

If you don't compete in SPL organizations much of this stuff will have no use or meaning to you. As with automobile drag racing... where most folks find a 4000 horse-power vehicle that only goes straight to be useless for their needs but it is designed for that sport and for that application. Asking what my box does at 29 Hz is like asking the 4000 horse-power drag-races how he does on an Indy track //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Pssh, you know you'd like to take a 10second car on a Le Mans race...

 

[retrojordans 10+ year member]

I should have bought that **** thing...Let me know if you want to sell it after all.

 

[retrojordans 10+ year member]

Pssh, you know you'd like to take a 10second car on a Le Mans race...

Yep the Ol' Family Sportster..

 

[manyhobbies 10+ year member]

Sorry I hope I did'nt offend you. To be honest, my goal is to understand all this. I am hoping to create decent #'s at around 30hz with my new setup to be proud of I suppose. I think low hz high db's is the way to go. I just love the rumble the low hz does, to me nothing feels cooler. So from what I'm gathering here, it is much easier to hit high db's with higher hz then with low hz correct? Thats what I assumed anyway.

So as a novice, will people be more impressed with a 150db at 25hz or 160db at 50hz? That is a serious question.

Thank you for the information and explinations. Russ

The frequency depends on the vehicle. Larger vehicles peak lower and as you go to small vehicles the peak higher -- vehicles the size of or close to the size of my Jeep are usually 50-53 Hz. Larger SUVs can be in the high 30s to low/mid 40s. Very small cars can be in the 60s.
You tune for the vehicle peak for SPL. Small vehicles are preferable within reason for the higher frequency since it requires so much less excursion to achieve a given SPL -- for example... it would take 400% more excursion at 20 Hz than 40 Hz to do the same SPL (4x the excursion for a drop in octave). Obviously if you have a certain number of woofers for a class and they can move only so far and you want the highest numbers possible you want a reasonably high frequency to play -- so small to mid-size vehicles are very popular for competition SPL. Alternatively walling off a vehicle and reducing cabin size that way can also raise the resonant frequency of the cabin; so large vehicles with walls can peak high as well.

If you don't compete in SPL organizations much of this stuff will have no use or meaning to you. As with automobile drag racing... where most folks find a 4000 horse-power vehicle that only goes straight to be useless for their needs but it is designed for that sport and for that application. Asking what my box does at 29 Hz is like asking the 4000 horse-power drag-races how he does on an Indy track //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

For me as product designer it's a great way to test products to see what they can handle as this type of things generates lots of pressure on soft parts, lots of thermal stress and shock on coils, and so forth. Obviously it's not the only thing I do to test products but it certainly helps //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[manyhobbies 10+ year member]

Not bad for a old wagon. An 8sec pass would of been even better.

Russ

Yep the Ol' Family Sportster..

 

[retrojordans 10+ year member]

Sorry I hope I did'nt offend you. To be honest, my goal is to understand all this. I am hoping to create decent #'s at around 30hz with my new setup to be proud of I suppose. I think low hz high db's is the way to go. I just love the rumble the low hz does, to me nothing feels cooler. So from what I'm gathering here, it is much easier to hit high db's with higher hz then with low hz correct? Thats what I assumed anyway.So as a novice, will people be more impressed with a 150db at 25hz or 160db at 50hz? That is a serious question.

Thank you for the information and explinations. Russ

Louder is generally more impressive. Reaching 150db @ 50hz will be much cheaper than 150db @ 30hz...But that is on tones man. On music you will encounter 50hz bursts and 30hz bursts intermittently..

Don't even worry about DB for now...Just keep doing your research until you find the system that's right for you. Who cares what people are impressed by? Try to impress yourself.