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

[bass_lover1 10+ year member]

Ported enclosures usually start losing control of cone movement around one octave below tuning, which at 30hz and octave down would be 15hz. The enclosure would probably have a hard time keeping things in line at 20hz or so, but since the majority of music (excluding bass CDs and the likes) never plays that low, you shouldn't have much of a problem.

My enclosure is tuned to 30hz and I do not use a subsonic filter.

 

[tcguy85 10+ year member]

Ported enclosures usually start losing control of cone movement around one octave below tuning, which at 30hz and octave down would be 15hz. The enclosure would probably have a hard time keeping things in line at 20hz or so, but since the majority of music (excluding bass CDs and the likes) never plays that low, you shouldn't have much of a problem.
My enclosure is tuned to 30hz and I do not use a subsonic filter.

i was just about to say pretty much the exact same thing! you beat me to it.

mine is tuned to roughly 28-30hz and i turned my subsonic filter off. i don't see a need for it so why have it on.

 

[helotaxi 5,000+ posts]

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?

Actually the frequency of a filter is the half power point. I.E if the filter is set to 30 hz, the response is 3 dB down at that freq and rolls off according to the order of the filter from there. Setting a SSF to 20 hz will actually affect response at 30hz.

 

[tcguy85 10+ year member]

Actually the frequency of a filter is the half power point. I.E if the filter is set to 30 hz, the response is 3 dB down at that freq and rolls off according to the order of the filter from there. Setting a SSF to 20 hz will actually affect response at 30hz.

this is also true. that is one reason why i turned mine off. my amp just has an on/off switch for the SSF that is set at 25hz. i noticed a very slight loss of low end when i turned it on so i left it off. if it was variable i would set it one octave lower but i don't have that option. and like stated before, nothing will have a signal that low anyway so the sub won't get damaged anyway.

i think the only time a SSF is really needed is when your port is tuned to 35hz or above. even at 35hz tuning you should be ok if your not listening to bass mekanic, or "bass i love you"(which actually has a strong 7hz tone in it) and stuff like that.

i listen to rock/metal so i leave mine off.

 

[helotaxi 5,000+ posts]

I was running a tuning of 41Hz on my Assassins with no SSF and I had no problems playing whatever with around 400w each. The subs and the enclosure volume play more role in the need for a SSF that an arbitrary tuning value.

 

[tcguy85 10+ year member]

yea your probably right. good point.

 

[snoopdan 5,000+ posts]

Why would you want to tune to 30hz anyways?

my two 18's are in an encloseure tuned to 35 hz. ......add 10kw of power and you can see my A-pillars move //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[cad_3326 10+ year member]

so, if I am NEVER going to listen to/buy/give a dam about a bass mechanik/whatever... If I really am going to listen to rock/metal MUSIC for pure enjoyment, what kind of frequency do you think that i should tune to, and somebody tell me what sub would fit best... I thought I knew what I wanted, but now I'm thinking that I might be more happy with say a single idmax10 running 400rms or so (I know they can do much more, I just don't meed it). Help me out gents... and good responses, very nice, I appreciate all your responses guys.

 

[DBfan187 5,000+ posts]

33Hz