Some random questions

[cheeto 10+ year member]

Alright, I've had this AQ SD2.515 in my car for awhile now, and I have a few questions about some annoying as hell stuff that's been going on with it.

Setup so far -

Infinity 1600a amp

AQ SD2.515

I've set the gains correctly with a 40hz test tone, but the thing won't get anywhere near loud, hardly loud enough to rattle my mirrors. The only way I could get it to be loud is if I turned on the thing called "Loud MID" or something on on my HU. However, when I turned it on and played a song like BME click at 42, where I set the gains, it smelled like melting something. I know I'm dumb for that.

So today I did I set them again with a 50hz tone, making sure it was 0db. I did that and it's still not anywhere near loud. It was loud with the tone, but still not loud enough to rattle my mirrors like the 12w3 did.

I got bored and put in a 20hz tone. Turned it up to 42, which was the volume I set the gains at. Went to the back to check the excursion, and It started making this huge and scary rattling noise. I'm sure it was bottoming out or something. I don't see how it would get that much excursion from a 20hz tone, but nothing from a song.

It's confusing me how a 12w3 got much louder with the gains set correctly compared to a sd2.515 with the gains correctly... each had 100w over their rms rating (w3 had 400w@4 ohms, sd2.5 has 600w@2 ohms)

This is really making me mad.

Questions so you don't have to read all of the above to get them -

Why is it only getting loud on tones, and not that loud at that?

Why is it that my 12w3 bumped harder?

Why do I have to turn loud mid on to get it to move?

Why did it make that noise (probly bottoming out) on the 20hz tone?

Any help is greatly appreciated seeing as I'm pissed as hell right now.

Click to read more...

 

[skateboardkid 10+ year member]

that sub in a sealed box might have this problem you are describing.

And if it was ported at 20 Hz it is working free air, =bad.

Your better off with the 40 Hz test tone.

If it is ported you might be getting some insane impedance rise or something arghhh post more info

1. Enclosure size and tuning?

2. How did you set your gains correctly?

and to answer

1. Not sure this sub has enough linear excursion to dominate that JL in output.

2. Enclosure?

3. Mid loud should not have to be turned on with 600rms

4. probably bottoming out or hard clip from the amp.

 

[cheeto 10+ year member]

Naw I meant like, I played the 20hz tone. The box itself is around 4.5 cu feet tuned to around 38 hz.

 

[skateboardkid 10+ year member]

Below you tuning frequency you are essentially playing your sub free air is what I mean.

 

[skateboardkid 10+ year member]

Do you have a SSf - subsonic filter on your amp? maybe it got turned on?

That box and tuning should be murdering the single Jl in output.

Box dimensions and port length x area, someone on here can double check your tuning frequency

 

[cheeto 10+ year member]

Below you tuning frequency you are essentially playing your sub free air is what I mean.

Oh I gotcha, I was reading that wrong.

I know mid loud shouldn't have been on with 600rms, I was testin it to see what would happen. I was really mad at the time cuz I was all juiced about getting a 15 and making my own box and stuff, only to find out the 12w3 was louder.//content.invisioncic.com/y282845/emoticons/verymad.gif.3f39c5c2fd57527b671fad3efdfac756.gif:verymad://content.invisioncic.com/y282845/emoticons/verymad.gif.3f39c5c2fd57527b671fad3efdfac756.gif

more info

impedance = 2 ohms, 600rms

box = 4.5 cu ft, ~38 hz

To set my gains, I took the speaker wire out, put the two probes from the DMM in, turned the HU to 42 (about 3/4 the hu's full volume), and slowly turned the gain to around 34 volts (that number came from subwoofertools.com)

I really need to find an oscope around here to test to see if its clipping.

 

[skateboardkid 10+ year member]

Its clipping that would sound audible to the ear most likely

I realize that you were just running mid bass to get some out put not dissin.

1. Give port length and width or circumference.

2. Do you still have JL?

 

[cheeto 10+ year member]

Do you have a SSf - subsonic filter on your amp? maybe it got turned on?
That box and tuning should be murdering the single Jl in output.

Box dimensions and port length x area, someone on here can double check your tuning frequency

That's why it's making me go crazy. I know that the sub was made for daily spl, vs the jl, which was made to go in the trash can.

There's no ssf on the amp

oh and box and tuning - I got it from the RE Thing

The tuning got changed a little higher during the whole process.

There's only 2 things I can think of.

1. The sub is actually a hdc315. Really doubtful, but it has the same basket+dust cap of the hdc, and the suspension is real stiff. Maybe it's got the suspension of a hdc3? I don't know.

2. The amp originally had a remote to it.. I'm thinking that my friend may have had it turned down last time he had it in his car, and that setting just stuck (ive never plugged a remote into it) but that's also a dumb reason, I doubt it works like that.

Oh and for your last 2 quesitons

Yeah I still have the JL but it's in need of a recone, makes an odd rattling noise when I tap the cone. I think it was messed up when I bought it.

The other one is answered above haha.

thanks a hell of a lot for the help so far.

 

[skateboardkid 10+ year member]

Have a quick look at the Audioque site for me and look real close at the baskets and cone

If you have the AQ on your cone, instead of the Audioque, and a fat *** magnet, and the HDC basket.

like click on the side view of each image so they get real big and compare them.

If you have the HDC3 that would explain a lot. Though it would leave us with almost more questions.

if so I would pm DJL I think he runs that site.

 

[cheeto 10+ year member]

Have a quick look at the Audioque site for me and look real close at the baskets and cone
If you have the AQ on your cone, instead of the Audioque, and a fat *** magnet, and the HDC basket.

like click on the side view of each image so they get real big and compare them.

If you have the HDC3 that would explain a lot. Though it would leave us with almost more questions.

if so I would pm DJL I think he runs that site.

Yeah, I've been looking a lot at them.

I'm positive it has the same basket as the hdc3, the sd2.5 on the site has 4 connecty things, whereas the hdc3 on the site has 8 or 10 or something. It's curvier basically.

The dust cap is also the one on the hdc3 on the site, says AQ and not the usual Audioque logo.

The magnet, however, is different. It's only double stack whereas I'm pretty sure the HDC3 is triple... and there's no rubber guard around it.

I was gonna email DJ but didn't wanna sound like a moron. I think maybe whoever was assembling with it accidentally used the suspension/spiders/whatever of an HDC3, along with the basket and whatnot.

BUT does that explain why it got loud when I turned some bass enhancement stuff up?

I really hope that's the problem, that would be cool lol

 

[w00tah 10+ year member]

Have a quick look at the Audioque site for me and look real close at the baskets and cone
If you have the AQ on your cone, instead of the Audioque, and a fat *** magnet, and the HDC basket.

like click on the side view of each image so they get real big and compare them.

If you have the HDC3 that would explain a lot. Though it would leave us with almost more questions.

if so I would pm DJL I think he runs that site.

He RUNS that company. DJL is the owner of AQ.

Kef

 

[skateboardkid 10+ year member]

Throw the JL back in there just to make sure if that possible.

Double check all your crossovers and inputs. Triple check its gotta be something funny with the setup.

 

[cheeto 10+ year member]

Throw the JL back in there just to make sure if that possible. Double check all your crossovers and inputs. Triple check its gotta be something funny with the setup.

I'll put the JL back in tomorrow.

But, as for just now, I checked the crossovers... HPF and LPF are both at 80hz, amp and hu. No bass enhancement, everything is set to normal on the HU.

Is it possible that a VC blew out? Would I just test that by connecting the DMM to the pos and neg end of each vc and setting it to ohm to see if anything happens

I'm still thinking it might be a suspension issue... anyone out there who has an sd2.5 - do me a favor and push on the cone a lil bit (I know its a bad thing to do lol) and tell me how stiff it is. Mine feels reaaaalll stiff compared to a cvr/w3.

 

[skateboardkid 10+ year member]

do you have your HPF on and going to your sub amp?

probably not but I gotta ask.

You would want just your Low pass filter on your amp on, nothing on the HU affecting the sub amp signal.

Turn off all high pass filters going to sub amp. and turn it off on amp.

if you have these both on that woudl give you almost no signal except when you turned on your mid bass to beat the overlapping crossover points.

If im wrong just continue with your quest.

 

[cheeto 10+ year member]

do you have your HPF on and going to your sub amp? probably not but I gotta ask.

You would want just your Low pass filter on your amp on, nothing on the HU affecting the sub amp signal.

Turn off all high pass filters going to sub amp. and turn it off on amp.

if you have these both on that woudl give you almost no signal except when you turned on your mid bass to beat the overlapping crossover points.

If im wrong just continue with your quest.

If that works,

A. Have my babies.

B. I'm dumb.