Will a vented box tuned to 30hz be likely to damage subs in daily use?

[cad_3326 10+ year member]

I've decided that overall, the best way to go with my subs is to use two id8's...

Now, I thought that I was going to use a sealed enclosure, but I'm a little scared that I may not get enough response out of them, so I'm thinking that I might go vented, but I've never built a vented box or even really considered one... So, the ID website has a box diagram for tuning dual id8 vented box to 30hz... I listen to hardcore, metal, rock, classic, etc..about anything with a heavy guitar in it and I may push these to their listed rms reguallarly. Assuming that I do push them at rms almost daily, and assuming that I'm listening to my ususal music>

Are the id8's likely to break trying to push out too much low frequency bass?

Click to read more...

 

[ThatChevyGuy 5,000+ posts]

not if you set your gains correctly and have a ssf.

 

[cad_3326 10+ year member]

OK, so my H.U. Eclipse 8455 runs a subson. filter, but do you mean to turn my gains down? That is equivalent to lowering the wattage running to the subs though right? Loss of power would defeat the purpose of increasing the output of the subs though..right? So I'm not really following you. Help me out.

 

[ThatChevyGuy 5,000+ posts]

No, im saying set the gains with a dmm to match the output from your rcas, so you dont have any distortion.

 

[cad_3326 10+ year member]

I guess that I could set a high pass x-over on the sub, at about 30hz for 18db/octave as well... then, by 20hz the output would be down to oh say... -12db, that might work. What do you think? Maybe even set the x-over at 26hz, then at 20 I would have about -9db... that might do it too, and the full 150 rms @ 26hz... do you think that that would lead to sub problems?

 

[cad_3326 10+ year member]

Oh, I don't know what dmm is, but I can check the power output on my amp with a multimeter, right? to make sure the power is what I think it is?

 

[cad_3326 10+ year member]

Man, I'm doing my best here, there's no need for that. He helped me out, and I appreciate it. If he's tired of my dumbass responses, I honestly understand... I'm not advocating an ethic that requires his response. That's uncalled for ksitka. And I don't know what calculate and set means...but I guess if I asked for that clarification it would be totally out of line! Besides, why even respond... I'm sure he has the balls to tell me that I'm a worthless @$$hole when he feels like it, and I'll understand, cause at least he tried to help... You on the other hand...

 

[Wkbdkid 10+ year member]

Theres a gain setting tutorial in the amp section. Read that tutorial and the things that he suggested should clear things up. If not come back an ask more questions, no big deal.

 

[HellsRise 10+ year member]

Oh, I don't know what dmm is, but I can check the power output on my amp with a multimeter, right? to make sure the power is what I think it is?

dmm = digital multimeter

 

[vehementSPL 10+ year member]

Well no matter what the tuning from what I remember it is hard to get a sub to be loud below its FS. I am not sure what the subs fs is. But as far as breaking it... Doubtful. Most boxes tuned low don't allow much excursion till you hit REALLY low freq

 

[86yota 10+ year member]

Why would you want to tune to 30hz anyways?

 

[dragnix 5,000+ posts]

30hz tuning is sweet, but i prefer mine at 32 //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[86yota 10+ year member]

Just seems to low to me. 32 is the lowest I would go. But thats just me, do what you want bro!

 

[groundpound4200 5,000+ posts]

A sub in a vented ecnlosure will have the least amount of excursion playing at the tuning frequency and most of the sound will come from the port at that point. By tuning low you are actually safeguarding your subs from overexcursion. Start with the SSF at 30hz, and while playing bass heavy music slowly turn up the gain till you get sufficient output without distortion. Then you can mess around with the SSF again. Hope that helps....

 

[Immacomputer 10+ year member]

Don't set your SSF at your tuning frequency; that's retarded as the cone will be the MOST controlled there and there will be very little excursion. If the enclosure is tuned at 30hz, there will even be significant cone control at 25hz.

And it's OK to put a sub in a ported enclosure that is tuned below the Fs of the driver. It does lower its efficiency in the enclosure but that does NOT mean it won't be loud or have a flat response.

My single eD $5 8" plays just fine in an enclosure tuned to 30hz (three cubic feet net volume as well) and it shares an almost identical frequency response in room as my av12 in 2.2 cubes tuned to 32hz. The Fs on the av12 is 24.8hz while the 8" is 32hz and people have measured them in the 50s. What does that tell you?