In search of new Sub, Please help

[Thumpper 266]

 there is not much more that can be done with out physically listening to it

I have built enclosures for Exterra's and had no issues with cancellation or distortion off the hatch

 

I would take it up with the shop you got it from and make them listen to it and see if they will deal with it 

[Thekid5678 3]

 there is not much more that can be done with out physically listening to it

I have built enclosures for Exterra's and had no issues with cancellation or distortion off the hatch

 

I would take it up with the shop you got it from and make them listen to it and see if they will deal with it 

When I went in and told them that I wasn't happy, they said "That thing was slammin when it left here".  

I then said, well anything over 37hz sounds good, but anything lower sounds like shit.

They said, well the box was built to Sundowns specs, 

I said, well It's not hitting low at all like I wanted it to. Plus the carpet is coming off, the subs arent flush mounted like I wanted, Plus the trim piece that you all designed to try to make it look like is is flush mounted is breaking away from the box, and the over all design is not what I wanted. 

They said, well schedule an appointment, and we will look at the carpet and the trim piece. 

I think at this point, I should just try to get my money back and go elsewhere.  

The shop has done good work in the past, but after talking here, and posting my pictures. I obviously did not get my moneys worth.

[Jay-C76 333]

Good luck trying to get that cash back.

Should've used a card, you'd atleast have charge back rights on disputes.

[///M5 2,833]

I don't think it is fair to ask for your money back. It is however fair to make sure they deliver what you paid for, but I also think you may have misled them a bit in that regard. I've NEVER seen a shop not at least try to build what was asked for. Sure they might fail often, but the key word was try. In this case I think they built what you asked for. Not quite sure how it could be so confused otherwise.

You are also probably in the wrong mode of expectation for what you can get out of the drivers you have. They aren't magic...

[Thumpper 266]

I don't think it is fair to ask for your money back. It is however fair to make sure they deliver what you paid for, but I also think you may have misled them a bit in that regard. I've NEVER seen a shop not at least try to build what was asked for. Sure they might fail often, but the key word was try. In this case I think they built what you asked for. Not quite sure how it could be so confused otherwise.

You are also probably in the wrong mode of expectation for what you can get out of the drivers you have. They aren't magic...

 

not Magic....

  I modeled them with multiple tunings and volumes.....they are not a really low digging sub

 

after modeling that enclosure , with the port velocity I doubt there is port noise I am almost thinking there

is some rattling going on in the hatch area that is keeping up with the output of the subs ..your problem might not be the enclosure

 

I would be doing some sound deadening asap

 

 

the shop should at least fix the carpet and the trim peice...I'm pretty shure if you asked they would add to the port and drop the tuning

 

if you want to drop the tuning to 30hz add 3.8 inches to the port length

[Thekid5678 3]

I couldn't have been more specific when I told them what I wanted. As for rattling, there is little to none. I have sound deadened it

[///M5 2,833]

I couldn't have been more specific when I told them what I wanted. As for rattling, there is little to none. I have sound deadened it

so you told them net volume, port tuning and port area or did you tell them exactly what dimensions for everything? If not you were not specific enough.

[antoinez28 62]

Thekid5678...I highly dought you get any money back alot of shops aroind kc area will not do refunds they will try and help if not lose cause I told you I will help you since im local I will be at the car meet and there will be other guys there that can help you also on the 23 of this month

[95Honda 486]

 

 

from what I can tell the subs are split apart by a double screen door brace and the port

( say good bye to acoustic coupling ) ...you just lost up to 3db right off the bat before you even turn the subs on

 

 

Kind of a misleading statement...  The drivers could be completely dis-coupled (as you state it) and loose zero net output if there are no phase differentials...  It is simply about phase issues between drivers, that is rarely an issue if the box is somewhat symmetrical...  In a properly build enclosure, there is never any output gained by common airspace, the only exception being minimum vent dimensions...

[Thumpper 266]

 

 

 

from what I can tell the subs are split apart by a double screen door brace and the port

( say good bye to acoustic coupling ) ...you just lost up to 3db right off the bat before you even turn the subs on

 

 

Kind of a misleading statement...  The drivers could be completely dis-coupled (as you state it) and loose zero net output if there are no phase differentials...  It is simply about phase issues between drivers, that is rarely an issue if the box is somewhat symmetrical...  In a properly build enclosure, there is never any output gained by common airspace, the only exception being minimum vent dimensions...

 

 

not completely

I made that statement after years of testing with a termlab  , I'v even  built removeable baffles so I could test the difference with the

subs together and apart  , the improvement is not always dramatic but I always get better results with the subs almost kissing each

other in the same cavity 

the old school rule of thumb is to be with in a voice coil diameter of each other but I try and keep them about an inch apart

 

 

 

Mutual Coupling of Loudspeakers

Mutual coupling of two or more loudspeakers occurs then they are reproducing th same signal with their acoustic centers close together and pointing in about the same direction at wavelengths smaller than the distance between the two centers. The combined sound signal is propagating forward like one single waveform, the two or more smaller drivers behave like one larger one. 

The centers of two loudspeakers must be close enough together between 1/4 wavelength and 1/2 wavelength. The higher the wavelength the shorter the necessary distance between the two centers to build up mutual coupling. 

The actual effect is always direction depending because of cancellations off-axis. Actually (theoretically) the coupling exactly on-axis occurs always independent of the spacing. At smaller wavelengths cancellation occurs earlier off-axis. At longer wavelengths the angle off-axis without strong cancellations is larger. The mutual coupling should be seen a an effect of the average sound level on-axis and off-axis. The acoustic centers' distance and the wavelength of the signal actually determine the angle over which mutual coupling occurs.

no mutual coupling with acoustic centers 

more than 1/2 wavelength separated mutual coupling with acoustic centers 

less than 1/2 wavelength separated

With two loudspeakers next to each other at a distance of more than the wavelength of the reproduced frequency the average measured volume on-axis and off-axis adds up for +3dB (double power). With two loudspeakers close enough to get mutual coupling the volume adds up for +6dB. 

Because of the physical size of loudspeaker chassis mutual coupling always occurs only at frequencies below about 500 Hz.

[95Honda 486]

Like I said, it is a phase issue.  It is more than just driver spacing...

 

**Edit** 

 

And don't forget, just like any acoustic/electrical phasing/coupling as you increase efficiency by decreasing radiated pattern/beamwidth, it does just that...  So phasing can become a serious issue and is why you'll never really see those huge gains.

 

I'm not saying you wrong, I am just saying there is so much more to this than simple driver spacing.

[antoinez28 62]

from what I can tell the subs are split apart by a double screen door brace and the port

( say good bye to acoustic coupling ) ...you just lost up to 3db right off the bat before you even turn the subs on

Kind of a misleading statement... The drivers could be completely dis-coupled (as you state it) and loose zero net output if there are no phase differentials... It is simply about phase issues between drivers, that is rarely an issue if the box is somewhat symmetrical... In a properly build enclosure, there is never any output gained by common airspace, the only exception being minimum vent dimensions...

not completely

I made that statement after years of testing with a termlab , I'v even built removeable baffles so I could test the difference with the

subs together and apart , the improvement is not always dramatic but I always get better results with the subs almost kissing each

other in the same cavity

the old school rule of thumb is to be with in a voice coil diameter of each other but I try and keep them about an inch apart

Mutual Coupling of Loudspeakers

Mutual coupling of two or more loudspeakers occurs then they are reproducing th same signal with their acoustic centers close together and pointing in about the same direction at wavelengths smaller than the distance between the two centers. The combined sound signal is propagating forward like one single waveform, the two or more smaller drivers behave like one larger one.

The centers of two loudspeakers must be close enough together between 1/4 wavelength and 1/2 wavelength. The higher the wavelength the shorter the necessary distance between the two centers to build up mutual coupling.

The actual effect is always direction depending because of cancellations off-axis. Actually (theoretically) the coupling exactly on-axis occurs always independent of the spacing. At smaller wavelengths cancellation occurs earlier off-axis. At longer wavelengths the angle off-axis without strong cancellations is larger. The mutual coupling should be seen a an effect of the average sound level on-axis and off-axis. The acoustic centers' distance and the wavelength of the signal actually determine the angle over which mutual coupling occurs. no mutual coupling with acoustic centers

more than 1/2 wavelength separated mutual coupling with acoustic centers

less than 1/2 wavelength separated

With two loudspeakers next to each other at a distance of more than the wavelength of the reproduced frequency the average measured volume on-axis and off-axis adds up for +3dB (double power). With two loudspeakers close enough to get mutual coupling the volume adds up for +6dB.

Because of the physical size of loudspeaker chassis mutual coupling always occurs only at frequencies below about 500 Hz.

So would this still work when using 4 subs or more a inch apart

[///M5 2,833]

Number of drivers is irrelevant, but spacing is. Not from driver to driver but from any driver to any driver. The results in a car with a sub will not match the equation though.

[Triticum Agricolam 15]

Number of drivers is irrelevant, but spacing is. Not from driver to driver but from any driver to any driver. The results in a car with a sub will not match the equation though.

Why won't car subs match the equation?  Seems to me getting acoustic coupling with subwoofers in a car audio environment should be a pretty easy task.  Even as high as 100 Hz the half wavelength will still be over 5 feet. 

[antoinez28 62]

Update did you get your miney back

[Thekid5678 3]

I have been in Cancun. I get back home tomorrow, and they are supposed to talk to me.

[Thekid5678 3]

Hey guys, sorry I was gone for soo long.  The shop rebuilt a box with a design that I gave them. I then did several modifications to my truck and went to Slamology.  Here are some pics, and a flex video. 












146.18 


Also, here is a video on the system in action with all the new changes

I am loving it, other than the fact that I have destroyed every roof brace that I have.  That will be my project next weekend, to get the headliner out re-weld the braces and get more support and sound deadening in the roof. 

[antoinez28 62]

Damn I wish you would of told me you were going to slamology I was there....with team iak

[Notorious97200 339]

146.18 ? You're loud now !

Congratulations.

I'm glad you finally have what you wanted.

[Thekid5678 3]

146.18 ? You're loud now !

Congratulations.

I'm glad you finally have what you wanted.

Yup, 146.18  I am thinking I could push 148-150 But I need a bigger amp lol.. Also I have shattered all of my roof braces, and that isn't helping things either. 

And Antoine, where were you parked at?

[antoinez28 62]

Around gate 3....I was not competing just there to help a fellow teammate out...

[Aaron Clinton 2,372]

 

 

Still looking for ideas :-) 2 15's and amp for around $900 or so. Less than $900 would be good though.. Gotta save some money for the box

http://store.soundsolutionsaudio.com/products/sound-qubed-q1-3500d-1-amplifier.html

http://store.soundsolutionsaudio.com/products/gcon-15-sound-solutions-audio-15-750w-gcon-series-subwoofer.html

 

Thats around $1400.   Too much for my budget

 

We can combo discount and order if you want to.

[Thekid5678 3]

Removing my message. Sorry.

Edited June 17, 2015 by Thekid5678

[Tirefryr 1,742]

Even if it was old, he was trying to help and save you some money. 

[Thekid5678 3]

Removing this one as well 

Edited June 17, 2015 by Thekid5678