Hz??

[502CEC 10+ year member]

So I went to a comp Saturday held by meca just to check it out and have my system metered. The judge acted like I shouldn't play tones lower than 38hz unless my system was designed for that he said. So what is the lowest I can play safely? My box is tuned to 34hz and my subs are the txx-bf15's by audiopipe. @38 hz (with my gaines turned down cause subs haven't got broke in yet) I hit a 147.5, so im wondering will lower notes put up better #'s if so how low is to low? Thanks

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[sacsking916 5,000+ posts]

lower tuning hits lows more and moves more air.

 

[ahole-ic]

You have to find your peak freq. That is the loudest note. There is no way to know whether it will be higher or lower because your tuning will change once the box is placed in your car. Not a lot of people on this forum know that, but not many are competitors either.

 

[i2ain2thunder 10+ year member]

you can always check em all and see whats the loudest/moving the most air. good to have a termlab on ya but just about anything will do that will sport numbers, just look for the highest

 

[502CEC 10+ year member]

would the easiest way to find the peak be to just plug it in and try diff. notes?

 

---------- Post added at 01:46 PM ---------- Previous post was at 01:45 PM ----------

 

thanks

 

[ahole-ic]

All total BS. There is no way to find your peak without a TL. Don't listen to these guys. Just find someone with a TL and work something out so you can test on it. You can't find your peak by ear... not even close....

and yeah try different notes. Start just above where you think you're tuned and go up. You should see the score rise, then stop rising, then gradually fall off. From there it's easy to see what your peak was, and why it's called a peak.

 

[502CEC 10+ year member]

so in theory i can look at the subs while playing and see which notes make the subs flex the most, just to get a starting point????

 

---------- Post added at 01:48 PM ---------- Previous post was at 01:48 PM ----------

 

Thanks ecrack

 

[ahole-ic]

so in theory i can look at the subs while playing and see which notes make the subs flex the most, just to get a starting point????

no. That was a stupid suggestion made by someone who didn't know what he was talking about. Don't listen to that. At your peak frequency, your subs will be the most controlled that they ever will be. They will actually be moving less. Playing well below tuning results in less SPL and MORE cone movement. Again, don't listen to these guys they don't have a clue.

 

[sacsking916 5,000+ posts]

you need a tl and the ability to constantly change your box tuning. and keep playing different frequencies til you find the peak one

 

[ahole-ic]

you need a tl and the ability to constantly change your box tuning. and keep playing different frequencies til you find the peak one

You don't need the ability to constantly change your box tuning.

 

[sacsking916 5,000+ posts]

You don't need the ability to constantly change your box tuning.

ok maybe not to that extent your right.

 

[ahole-ic]

ok maybe not to that extent your right.

I'm not trying to insult you. This guy just asked a legitimate question and I just wanted to help him. Anyone that is wanting to compete, I really want to help them and encourage them to do so. Sorry if I have come off as a douche.

 

[wickedwitt 10+ year member]

TL meter, an SPL disc with both a sweep and all frequency songs. Run the sweep (at low volumes if you are at a comp so you don't a: destroy your batteries b: destroy your subs) to find your loudest note.

Go to that tone (usually 45hz is track 45 etc) and play it at the loudest you can go without clipping (normally the loudest you'd ever play music on if your amp(s) are properly set).

Win a trophy.

????.

Profit

Once you've found your peak, as long as no variables change (box design, placement, amp settings, etc), just go straight to that track at comps from then on. If something has changed, do the sweep again to make sure your frequency hasn't changed.

 

[sexy 10+ year member]

When you play music under the tuning of the enclosure its not as likely to be real hard on your sub as playing tones for three seconds strait. When you play anything below the tuning of the box you loose back pressure. That pressure helps control the movement of the sub so that it moves in and out the right amount and moves strait not damaging the coils on the sub.

If I were running a competition and someone asked me about playing under the tuning of a box I would try to explain all I could to them. You should not need to play under that box tune though. I will explain; most people going to compete with a regular daily driver are going to see that their peak note will be right around 45hz give or take a couple.

So the judge was playing it safe with that answer and giving you a chance to learn more about your system. He also probably knows from years of experience (like me) that you will not need to play that low to get your best score. 147.5 is pretty good for someone just learning you should be happy with that.

If you get to go again do a sweep from 40hz to 60hz and you will most likely find that your peak is right around 45hz.

Another point here is that it was meca and in meca you are allowed to have a door or window open. With a door or window open you have less back pressure inside the car to help control the movement of the sub I forgot to mention that before.

 

[sacsking916 5,000+ posts]

I'm not trying to insult you. This guy just asked a legitimate question and I just wanted to help him. Anyone that is wanting to compete, I really want to help them and encourage them to do so. Sorry if I have come off as a douche.

not insulting to me. i bassrace so i dont necessarily need to worry about peak frequencies being that i play music during my runs. now if i was building a spl build for one hit wonders then yes i would go through the extensive process to squeeze every single db out of it.

but im always willing to learn more