Calling BS on "breaking in" subwoofers, prove me wrong.

[thorshammer1 10+ year member]

How about showing where you come up with amps are more efficient at high frequencies? I am very interested to know why and by how much? Unless you've done too much work to find out and don't want to give away your secrets.

I believe your answer lies within... A sub playing 70hz requires very little movement to play that note. A sub playing a 30hz tone requires more energy to generate said tone. It takes more energy to throw the coil,stretch spiders and surround at lower frequencies thus causing a harder strain on your electrical system, thus causing more voltage drop. I have noticed this many times over in my own vehicle. lol

 

[outsideshot23 10+ year member]

Yeah, I guess I could buy half a dozen speakers and play and test them over the course of 4 or 5 weeks or just read what happened when someone else did it. LOL. I got my answer in half a day and for free. Reading is pretty stupid huh?
Well, I suppose you're just better than me in every way and don't have to provide facts or data to back up anything you say.

Honestly it's stuck up ***** like you why I never competed before last year (out of 20+ years in the hobby). People that know everything, can prove nothing, and won't share all their infinte wisdom are the cancer that has killed car audio competition.

How about showing where you come up with amps are more efficient at high frequencies? I am very interested to know why and by how much? Unless you've done too much work to find out and don't want to give away your secrets.

well you wont listen to people who have tested them.. lol.. so ya.. you are pretty stupid

 

[outsideshot23 10+ year member]

I believe your answer lies within... A sub playing 70hz requires very little movement to play that note. A sub playing a 30hz tone requires more energy to generate said tone. It takes more energy to throw the coil,stretch spiders and surround at lower frequencies thus causing a harder strain on your electrical system, thus causing more voltage drop. I have noticed this many times over in my own vehicle. lol

its common sense to anyone who knows car audio.. OP is obviously a newb and has never tested anything... but can find someway to discredit anything posted by someone who has put in the hours.. thread is a fail

 

[outsideshot23 10+ year member]

higher notes are electrical froendly.. Try running an amp at 16V and run it again on 12 and see which wayt it gets hotter. High freq=less strain on electricl=less strain on amps=efficiency.. not rocket science.. and like i said you want allt his published this and that.. The competitiors doing this on a daily basis are not authors and im not writing blogs. I have over 12k$ in my current system and am on a TL DAILY.. i tests every week and i go through equipment like crazy. because i havent wront e a book and documented everythign doesnt mean i dont know what im talking about.. and ya i do have it written down in a notebook but im not going to give every spec of info i worked hard for to some idiot who dont even know audio to begin with

 

[Kyle_Keating 10+ year member]

As previously stated, the biggest reason for break-in is for the spider. Spiders are made of cloth that is pressed and then dipped in epoxy. When you break-in a driver you introduce micro-cracks throughout the epoxy, which will make the spider softer. You can typically see a 20% drop in Fs over a lengthy break-in. But because Cms changes, your Fs will drop and so will Qt and Qe and Vas will increase.
Paul Roth of Credence did a test where he broke-in a driver for a long period of time and immediately tested the T/S's, let it cool down to room temperature and then tested the T/S's again on a M-130 model loudspeaker. *Note that this speaker has a much softer compliance than most car audio subwoofers

Here are the parameters immediately after a very long and hard break-in:

Fs: 46.9

Re: 5.5

Qms: 1.86

Qes: 0.33

Qts: 0.28

Cms: 1.64

Mms: 6.99

BL: 5.84

Vas: 20.69

SPL: 90.12

Le: 0.32

And here are the T/S parameters after it cooled back down to room temperature after several hours:

Fs: 49.9

Re: 5.5

Qms: 2.01

Qes: 0.35

Qts: 0.299

Cms: 1.58

Mms: 6.41

BL: 5.60

Vas: 19.99

SPL: 90.50

Le: 0.32

The driver he used had these parameters fresh out of the box:

Fs: 50.47

Vas: 18.64

Qt: .314

The greatest amount of change will occur right at the beginning of break-in, but the parameters will stabilize and show almost no change at all from continued use.

So what does all of this mean? For the end user, simply use your subwoofer normally. After a week or two everything should settle into a constant and you shouldn't see any change in the performance of the driver after that.

nitpick: The Re can't be the same for the hot coil and the BL can't be different.. I'm guessing the second test used the original Re value and then calculated an artificially low BL value? Either way, you get the right Qts and SPL, but its technically the wrong way of doing it.

The Re of the second test should be around 5.98 ohms and the BL should be 5.84 Tm... all other numbers remain. So you have a Dcr rise of ~0.5 ohms after heating up

 

[not_loud_enough 10+ year member]

well yesterday my AQ SDC2.5 10 came in the mail and the suspension was so stiff, i could barley push down on it... well its been hooked up for 9 hours now running off my home amplifier playing a 40 hz sine wave with about 1 inch excursion and let me tell you i just checked the suspension and i can actually push down on it now but not alot so im gonna let it play for another 5 hours and see if its ready to be unleashed in its 36 hz 1.7 cube box //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[thevic24 5,000+ posts]

With my 3512, it was loud as hell right out of the box but only so-so on the sub 45ish notes.

After a day or 2 of normal(for me) playing and a few demos, the sub 45ish notes did play much louder.

This is just my experience with this sub....

 

[Chriszle 10+ year member]

"How does this jive with the "fresh recones before the big show"? I can't recall ever seeing a thread "my DD sub is making funny noises" that turns out to be a failed tripple joint. Just saying..."

Fail Quote ^

DD says your subs will sound louder. What you don't understand is sounding louder to the ear is different then hitting high number on the meter. Most competitors arent playing their system to full potential for extended periods of time, a burp or two. I never said if you do not break in a DD sub it will fail, it just increases the possibility which at finals is well worth the risk in order to win.

 

[Electrodynamic 10+ year member]

nitpick: The Re can't be the same for the hot coil and the BL can't be different.. I'm guessing the second test used the original Re value and then calculated an artificially low BL value? Either way, you get the right Qts and SPL, but its technically the wrong way of doing it.
The Re of the second test should be around 5.98 ohms and the BL should be 5.84 Tm... all other numbers remain. So you have a Dcr rise of ~0.5 ohms after heating up

I found it odd too that the Re wasn't higher when it was just ran hard. I'm guessing that's the only parameter that he missed, as the other parameters shifted accordingly.

 

[outsideshot23 10+ year member]

"How does this jive with the "fresh recones before the big show"? I can't recall ever seeing a thread "my DD sub is making funny noises" that turns out to be a failed tripple joint. Just saying..."
Fail Quote ^

DD says your subs will sound louder. What you don't understand is sounding louder to the ear is different then hitting high number on the meter. Most competitors arent playing their system to full potential for extended periods of time, a burp or two. I never said if you do not break in a DD sub it will fail, it just increases the possibility which at finals is well worth the risk in order to win.

agreed... on a side note not sure what funny noises you are talking about but i know some of the new dds i have noticed at low volumes sounds liek the coil is ryubbing in the gap and turns out they have had some problems witht he spiders not breaking in evenly and one side will break in while the other is not and cause the gap to be off until it is fully broken in.. just an FYI for anyone with that problem