advice on subwoffers

[audioholic 5,000+ posts]

Whether it was the sub size or another factor, I don't know.

Let us know when you figure it out.

If you had understood 'the document', you would have never posed your following post as the answer is obviously it was from a different facor... or your ears are simply broken.

This topic has been discussed ad nauseam on this board and every other car audio board Ive ever frequented. You are wrong, the flawed notion cone size is a substantially contributing factor to SQ went out with the invention of the internet. Thank Al Gore, and welcome to the 21st century. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

A simple search of this topic, by you, would find an overwhelming amount of evidence that would make you realize you should forget you ever responded to this thread and just move on.

 

[thormotox448 10+ year member]

umm.... so anyways, back to my question. I plan on putting a new system in my jetta, and wasn't really sure what i wanted to do sub wise, run 2 12's again, 1 15, 2 15s? im not really sure what i should do. Any ideas?

 

[mrogowski 5,000+ posts]

While I find that document to be an interesting read, and Dan does a pretty good job of explaining things, I feel inductance doesn't play that big of a part with subs as many think it does. This is why:

Dan's test proves that the added mass method does not affect response - this is true. What I find interesting though is that the inductor used in series with the driver did not affect the driver throughout the entire passband - it only started affecting the response at ~1400Hz and above. Well guess what? That just so happens to be the crossover frequency for the size of coil he used (6db/oct).

What we are seeing is the effect of the coil at that frequency and above. Yet, everything is ok at 1400Hz and down. Is transient response affected at the frequencies below 1400Hz? According to what Dan has posted, I say no.

Subs work within such a short passband, that the only time inductance becomes an issue is at resonance. If resonance is pushed down to such a low level (say below 20Hz) the inductive nature or "slowness" of the driver for the most part won't be heard anyway. Also, at resonance (below 20Hz), the driver is moving less than 20 times per second and is moving the least amount, so this again makes inductance less of an issue.

A couple of ways to minimize the inductance at resonance would be to seek a driver with a very narrow (high Q) impedance peak so less frequencies are affected by this "slowness". Or a very overdamped design (very short peak) where inductance isn't as high.

Many companies post inductance measurements based on 1kHz. How many folks do you know run their subs that high?

Best,

Mark

 

[mrogowski 5,000+ posts]

umm.... so anyways, back to my question. I plan on putting a new system in my jetta, and wasn't really sure what i wanted to do sub wise, run 2 12's again, 1 15, 2 15s? im not really sure what i should do. Any ideas?

I think you can answer this yourself quite easily. Were you satisifed with what you had before? If so, then stick to the original plan. If no, go bigger.

Best,

Mark

 

[SeanDub 10+ year member]

RobertFielding

^^^^^^^^

Pretty funny. Kids trying to give someone else advice on subwoofers when he posts his own thread asking if a mini visonik amp will groundpound when paired with a "q power deluxe" after wanting to buy some Sony Explosions.

The rule in the classifieds says if you have a neg feedback thread that is unresolved you can't make a new for sale thread.

Here the rule should be if you want to upgrade your system by buying some Sony's you shouldn't be allowed to even look a thread in which someone else is asking for advice.

___________________________________________________________

Anyway, to answer the man who started the thread's question about what amp would go well with 2 12" TC-1000 subs. I think an Elemental Designs nine.1 would do them nice. The tc-1000 subs are rated at 400 RMS a piece and the nine.1 will put out 1200 RMS, giving them a little more than they're rated for, but they can take it. In a proper box, those will sound **** nice.

 

[SeanDub 10+ year member]

I'm not too familiar with the Jetta, but i'm pretty sure it's a compact to midsize sedan type car, so one thing you have to consider is trunk space - making sure that you can fit a proper box back there. 2 12s and 1 15 ported will take about the same amount of space, I can't see you getting two 15s back there. Both would generally take anywhere from 2 - 4 cubic feet depending on the woofer. I like the 2 12" TC-1000s idea or maybe looking into a 15" sub, like a 15" Resonant Engineering SX, Fi Q, or Digital Designs 2515, and you could run any of those off an Elemental Designs nine.1.

 

[thormotox448 10+ year member]

yeah after doing some research i think im going to go with 2 12 tc-1000. They are rated for 400 rms but does anyone know how much they can handle up to daily? Saw somewhere they can take 600 rms all day no problem.

 

[theCybe 5,000+ posts]

I thought it would be funny to edit this post.

 

[theCybe 5,000+ posts]

It's always Ohio.

 

[Grinder1989 5,000+ posts]

Dear mods,

Please implement a feature that automatically filters stupid complaints on an open forum.

signed,

Grinder

 

[phantom240 5,000+ posts]

Dear mods,

Please implement a feature that automatically filters asshats from life.

Signed,

phantom240

 

[Fi Car Audio 10+ year member]

lol... just skip to the last paragraph for on topic stuff.

ok... Ill run with the off topic inductance and speaker size portion of things then //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

Mark is definitely heading down the right path... and it has always amused me with all the snake oil swirling around the inductance rings being used in subs with 3" coils and 90mm ID magnets. Shoving a copper water pipe coupling into the gap doesnt really do squat in the passband of a sub. Great you have lowered inductance at your measured 1000Hz... but like Mark mentioned... what does that have to do with 40Hz? It takes a significant amount of copper or aluminum to reduce inductance down low.... and a 1mm thick ring simply isnt going to do it.

As mentioned before, 18" or 8" if it is properly designed and in the proper enclosure, there will be no difference in transient response or dynamics. Just swept volume and therefore output.

Now sort of back on track... there is no shortage of solid 12s and a good 1000+W amp that can be had and stuffed in your trunk for under $1k. Id really look for a good amp first, figure what it likes to make max power into and find a pair of subs that will meet that Ohm load and handle the power. Not sure what year your Jetta is, but I have fit a pair of 15s in the older Mk2s and the Mk3s. Takes some doing, but it will fit.

Thanks...

Scott