Issues with my Q

[Oni 0]

Ok, so I finally finished stage 1 of my install today. It's gonna take too much time for the custom fab needed for my components to fit in my door so I used a Line Out Converter to get me by. I couldn't change out my HU because of the factory amp and it would cause the speakers not to play and there is no harness for it yet.

Anyway, back to the point of the post. So I have my Q in a sealed box with about .8-.9 cubes after displacement. It's a cheap $20 prefab box. I'm just not happy with the current output of the sub. I've seen 10" Q videos, sealed and ported, where there was trunk flex and the rear view mirror noticeably vibrates, and this is only on 1000 watts. I'm running about 1200-1300 max off of my amp. Mine seems louder than the stock sub from the car and cleaner (I love the SQ from this thing), but I know it can get louder.

I tried setting my gains off of my DMM for 1200 watts rms coming from my Hifonics 1505D at 1 ohm with a 60 Hz -3db test tone. I got it all set and I was unimpressed with the output as I said. So knowing rock is recorded at something like -6 or -10 db, I reset it with a bass heavy song I listen to. Much better, but still not like what I've heard and seen this thing do. And if I tweak the gain slightly up to where it sounds better, the amp goes into protect mode well before I can hear clipping.

I did some trouble shooting and found some things. 1 or 2 of the screws for the sub weren't super tight and there was a small air leak so I went back and tightened everything up nice and good. That helped quite a bit, but still not perfect. I haven't checked the terminal cup/mount for air leaks yet, but it's a cheap box so there's probably some. Next, how sensitive is the Q to a box that's bigger than recommended; large enough to hurt its output a lot? I eliminated the LOC by hooking my IPOD to the amp and setting the gain the same way, and on the same song the output of the sub sounded about the same. Could it just be my amp? Would a fancy custom built ported enclosure make a huge difference and if so, anyone got some designs? It just confuses me how it's super clear compared to my factory sub, but only seems about 30% louder (Factory was only like, 100 rms 10").

Sorry for the long post and Thanks!

[bassahaulic 155]

Short answer:

It's the box........ That's all I can say.

[justin smith 0]

pre fab boxes are bad news

[Oni 0]

Short answer:

It's the box........ That's all I can say.

That's what I was figuring you guys would say.

I just thought of another question, if I have my subsonic and low pass filter set properly (Set using the appropriate test tones), what would cause the sub to make this weird quiet noise from the sub when only high frequency stuff is playing. It's like a low pitch rattle or almost like the sound coffee brewing makes. Do you think it might be noise from a bad ground on my Line Out Converter causing? Would it be ok to run some extra remote wire from my LOC to my ground distro block to see if this is it?

[NDMstang65 403]

Again, i've said it many times. Speakers are dumb, they do what you are telling them to do. Whether it is via the amp, crossover points, enclosure etc.

None of them have mechanical noise or rattles..it just doesn't happen.

Line-out converters often are a huge issue, i've heard of many problems with those amplifiers, and honestly a prefab box probably isnt going to help the situation either..

Plus your looking for a LOT out of a single 10" sealed woofer as far as output..

Thanks,

Nick

[Oni 0]

Well, I did some more digging. The noise is still there with or without the LOC (using ipod to send amp signal instead). The amp worked fine on the 2 Kicker subs I used to have so I have a hard time believing the amp is bad. I wouldn't be so disappointed with the output if I hadn't seen videos of more vibration on less power with the same speaker sealed to about the same volume.

Here are a few things I have questions on that may or may not be the cause of said noise.

1.) Would mounting the amp to the back of the rear seat through metal possibly cause this.

2.) What about a loose wire inside the box where it connects to the terminal. It is using the female quick connecters. A loose wire may explain issues pushing as much power as I should be able to.

3.) How could I tell if the amp is bad easily. There are no visable burn marks and everything seems fine other than the noise.

I know the speaker is fine fine itself because the coils show normal impedance values and there is no noise if I push on the cone.

Thanks

[xprime4 5]

are you the same oni than on ca???? lol i just asked the question about the little rattling sound on here too

good luck

[Oni 0]

So I figured out what's going on. The amp is sending a bad signal for some reason to the sub. Tried a different sub/box and it made the same noise. Dumb Hifonics. It worked a year ago when I used it last. Apparently Closet>Hifonics, since it hasn't moved from that one space in a little over a year, with nothing on top of it.

On that note, who's selling an AQ1200 or Sundown for a good deal!

[Oni 0]

I think i know what happened to my amp. When I first moved from Michigan to Texas, my engine died on my car after 152,000 miles. So I bought a new car, but didn't have my tools down here yet, so the dealership unhooked the amp and all my wires for me. I would bet they didn't disconnect the amp in the right order since I haven't used it since then and all of a sudden it isn't working.

[liljpw16 0]

I hate to say it but im pretty sure its your box. I have the ssd 15" and its in a ported box and this thing slams. I put it in a sealed box and was very unhappy. Replaced it the same day back in the ported. But maybe you are asking alot out of a 10" woofer. I wouldnt expect much out put out of one of those anyways. But to give you more output go PORTED! Here is a box design program that came in handy for me! Read up on box building before you take that first leap! Ive built many boxes and i have read alot before i did it. heres the link

http://reaudio.com/speaker_box/LPort_Box_Calc.html

Edited March 26, 2009 by liljpw16

[bassmaniac 0]

it's most likely the box...don't buy the one's they sell at the audio shops cause they are poop...buil or have a good box built to specs for the sub and go from there..

[///M5 2,833]

So I figured out what's going on. The amp is sending a bad signal for some reason to the sub. Tried a different sub/box and it made the same noise. Dumb Hifonics. It worked a year ago when I used it last. Apparently Closet>Hifonics, since it hasn't moved from that one space in a little over a year, with nothing on top of it.

On that note, who's selling an AQ1200 or Sundown for a good deal!

Get ready for future troubles that are similar with the AQ. Hifonics :(

The Sundown on the other hand will give you many years of good use, so get it but do build a real box at the same time.

[bassmaniac 0]

just like the guy above me mentioned, get a sundown amp...hifonics is good but canno't compare to sundown amps..also i'm not sure on your budget but another good amp brand is the amp i use! they are called titanium power, you can look them up on the web, not sure of your budget but i bought my 2400 for 450.00 (used) new they are like 600.00 range! and are worlds better i've owned rockford,kicker,and mtx amps!

[///M5 2,833]

just like the guy above me mentioned, get a sundown amp...hifonics is good but canno't compare to sundown amps..also i'm not sure on your budget but another good amp brand is the amp i use! they are called titanium power, you can look them up on the web, not sure of your budget but i bought my 2400 for 450.00 (used) new they are like 600.00 range! and are worlds better i've owned rockford,kicker,and mtx amps!

I am curious as to how and why you think the Titanium amps are worlds better than Kicker or Fosgate.

[bassmaniac 0]

just like the guy above me mentioned, get a sundown amp...hifonics is good but canno't compare to sundown amps..also i'm not sure on your budget but another good amp brand is the amp i use! they are called titanium power, you can look them up on the web, not sure of your budget but i bought my 2400 for 450.00 (used) new they are like 600.00 range! and are worlds better i've owned rockford,kicker,and mtx amps!

I am curious as to how and why you think the Titanium amps are worlds better than Kicker or Fosgate.

never said they were better, just throwing out another option..everyone has kicker,fosgate,autotek,sundown..what's wrong with doing something different? and also the titanium amps are cheaper than fosgate and more powerful, and why i think they are better than kicker is cause they actually go down to 1ohm..not to say kicker isn't good cause they are!

[Oni 0]

So I just ordered a Used US Amps MD1D that was in my price range. Should replace that junk Hifonics and get me up and going.

[liljpw16 0]

For your box i would do 1.0 cuft after all displacement tuned 33hz.

[///M5 2,833]

just like the guy above me mentioned, get a sundown amp...hifonics is good but canno't compare to sundown amps..also i'm not sure on your budget but another good amp brand is the amp i use! they are called titanium power, you can look them up on the web, not sure of your budget but i bought my 2400 for 450.00 (used) new they are like 600.00 range! and are worlds better i've owned rockford,kicker,and mtx amps!

I am curious as to how and why you think the Titanium amps are worlds better than Kicker or Fosgate.

never said they were better, just throwing out another option..everyone has kicker,fosgate,autotek,sundown..what's wrong with doing something different? and also the titanium amps are cheaper than fosgate and more powerful, and why i think they are better than kicker is cause they actually go down to 1ohm..not to say kicker isn't good cause they are!

Sure sounds like in your post you were stating they were worlds better.

Going down to 1 ohm is NOT a valid reason for calling something better. Perhaps someone has an installation where 2 ohm is beneficial. Lots of cases in fact. There are many reasons why running at a higher impedance is better as well, so throw that argument out.

[Oni 0]

OK, so I have my new amp and got everything installed. Now I have a new problem. When I fire everything up, my sub is playing with the radio volume at 0 and amp gain all the way over at 8V, but it stops when I push the button to turn the radio off and the rhythm changes when I change songs. When I use my Ipod, the volume changes with my Ipod volume and doesn't have this problem.

I didn't have enough time before the Sun went down to troubleshoot this anymore, but would this happen if I had the gains on my LOC too high? They are adjustable and I think they are all the way up.

PS - With the IPOD, The sub sounds amazing. So much better than with the crippled amp.

[dbjunior 0]

id turn down the loc

[Quentin Jarrell 671]

Is the sub playing or just rumbling? Pull your RCA's out of the LOC to make sure the rca's don't have a ground loop. If the sound stops it is most likely in the LOC. Try turning the LOC down and readjust you amp gain again to see if it stops. Line output convertors create a lot of hissing and it bleeds through when you turn down the volume on your headunit.

[Oni 0]

Like I said, It's actually playing. The bass output changes with the song and follows the bass in the song. I'll try the LOC gain adjustment tomorrow.

[Doctor Q 12]

I think i know what happened to my amp. When I first moved from Michigan to Texas, my engine died on my car after 152,000 miles. So I bought a new car, but didn't have my tools down here yet, so the dealership unhooked the amp and all my wires for me. I would bet they didn't disconnect the amp in the right order since I haven't used it since then and all of a sudden it isn't working.

is there a certain order to disconnect the wires from an amp? im wondering because i was going to move my box around some today and tomrw to test results and i need to unhook my amp in order to move my box.

i thought it'd be as simple as unscrewing the things, taking the wire out, moving the box, and then putting the wires back in.

leme know so i can get started. not im afraid im going to screw something up.

thanx,

alex

[Johnnymgl 1]

Do you still have that pre fab?

Trust me the next big thing you can do is getting a custom built box

You will be happy that you did

[suprefly 0]

Generally, just take the power wire out first, and the ground last.

And be careful hooking it back up too

Edited May 22, 2009 by FF5