I'm relatively new to car audio, but over the last month or so I've gotten the bug.

I currently have a 10 Infinity Reference 1030W in a sealed box that fits in the trunk well, above the tool carrier. I'm thinking of rebuilding the box so it will fit lower in the well. I'm estimating the box to contain just under 1 ft^3 airspace.

I picked up the sub from Crutchfield for $49.99 shipped and still have about two weeks of the initial 30 days to exchange it for free.

Since I will be constructing a new box anyway, should I return the 10" driver and pick up a 12" instead? The amp I have should power a 12" sub just fine (Profile ca800 bridged).

Is there a decent 12" driver, at a relatively low price (>$100), that will work better in a 1.0 ft^3 box, that will sound better than the 1030W? Maybe an Infinity 1230W or Alpine SWE-1242?



- Thomp

 

THe size of the sub doesnt matter. If you want serious bump, get the Alphasonik PSW-810.

 

i'd disagree....

the more air a sub displaces (moves) the louder it can be... a sub can only move air by 1 action, the in and out stroke.
longer strokes = more air displaced. BUT, if you increase the surface area of the sub, the same length stroke moves more air, which theoretically is more volume displaced.
this doesn't take anything such as quality of sound into account, it's just a 'moving air' thought process. other things like efficiency also have to come into play, as moving a huge cone even a little can require a lot of power.


all that being said? are you wanting more bass? does the 10" meet your needs? going to a 12" won't automatically give you better sound, as a bigger cone can be more subject to distortion, inefficiency, etc.
should you upgrade to a 12" i dunno... how does that 10" sound so far?

 

No no....i didnt mean the size of the sub actually doesnt matter. THis was just on an "this case" basis.

Obviously if we took the same alphasonik 10 vs 12, the 12 would perform better, but I am talking about some cheap a$$ 15" like a funky pup, it wouldnt hit like the alpha. So, I was recommending a better 10", instead of just getting a crappy 12.

 

So far I think the 10" hits plenty hard enough. I would like the frequencies lower than the song beat (20 - 30Hz?) to shine a little better, though.

For instance, I noticed yesterday that placing my roll of electrical tape on the trunk deck while testing my sub would cause it to bouce around and off the trunk, but on slower music with lower frequencies I really have to crank it to get the level I would like. I'm not entirely sure how to describe it, and my home theater sub (Adire Tempest 15" in a huge enclosure with 250W amp) is all I really have to compare to. When building it, I came to the conclusion that you needed at least one (or two) of the following:

a) surface area (with a decent driver)
b) enclosure volume
c) power

With the home theater sub, I went with a) and b) since getting a lot of power gets expensive. With my car sub, I have c), b) is restricted to just under 1 ft^3, and I'm unsure if upgrading a) from a 10" to a 12" will be worth it.

Maybe I'm expecting too much on a small budget? I read up on the 12" drivers I am considering and they all want too much airspace. It's not that I'm unsatisfied with my current sub/amp setup by any means, I just want to make sure I've maximized my dollar.

As always, thanks for the input.

- Thomp

 

Well maximizing your dollar almost NEVER includes swapping gear. So be sure you get what you REALLY want so you are not swapping in gear very often.

I personally think a 12" SW is overkill on an S2000 for normal people actually listening to music. (Competitions and bling excluded in other words.)

I honestly think the 10" I have is almost TOO much. I have it dialed back a little to mabey 80% of what it could EASILY handle and it still hits HARD. It's a little car. I barely have over 200 watts going to the sub. I have about 65-70 going to the components.

No reason to go nuts.

The next question I will ask you is how long do you want to spend tracking down rattles?

 

[QUOTE=ruexp67,May 24 2005, 07:48 PM]Well maximizing your dollar almost NEVER includes swapping gear.

 

gotcha.... yeah, in this case i'd readily say -- upgrade to a nicer 10" sub vs lateral change to a 12". and yup -- you cannot simply compare cone sizes to choose the better sub. the only time where the scaling of size works is within a similiar product line or comparable product lines... (where motors, excursions, efficiencies, power handling, etc. all remain close to the same...) not to mention, depending on the manuf. and the materials -- a larger diameter sub could get quite sloppy if the cone isn't rigid enough or gets too heavy.

the biggest improvement you'll get w/ a nicer 10" would be more control and better excursion for the sub. still, power requirements would likely go up as well... so, you could be looking at more money than you're willing to spend.

what you're noticing here is low frequency roll off of the sub. as the music gets to deeper bass, the sub isn't reproducing the frequencies at the same levels. (this is why reading that a speaker can go 20hz to 20,000 hz is meaningless if they don't include a +- dB figure.) if you go (laterally) to a 12" sub, you might lower your rolloff frequency slightly. no promises on how much, etc. i'd need to see frequency response numbers, graphs, efficiencies, etc. to make even an educated guess. it probably won't be much tho...

in the end though this is going to basically be a function of 2 things...
1. the sub is in a sealed enclosure. as the bass gets deeper, the power requied to move it for large excursion slow cycles increases because you're fighting the back pressure in the enclosure. this behavior is one of the disadvantages of a sealed enclosure, and there are few ways to get around it. (this is over simplified, but hopefully will help... a large volume enclosure is better for this b/c the displacement of the driver's stroke represents a smaller percentage of the total volume of trapped air, thus the back pressure increases are lower for the same excursion. however, not every driver is designed to be dropped into a bigger enclosure to get deeper sound...)
2. the sub you have is pretty inexpensive, so the motor (voice coils, magnets, etc.) are going to be pretty wimpy... thus, they don't have the 'strength' to drive against that increasing back pressure when compared to a more expensive sub... so, you also get roll off there as well. but, your sub also has less mass to move, so it requires less power to get pumping. if you go w/ a bigger motor to get the lower frequency extension -- you're going to need much more power. so, upgrading your sub may lead to the need to also upgrade your amp.
(example -- my e8A had a gigantic motor on it, and for a little 8" sub required a ton of power to get even reasonable output from it... but it also could play very very deep relative to other 8" subs.)


given everything-- i would stick w/ your sub as is.... a 12" will require more volume (less trunk space), and may only slightly improve your low frequency extension. if you're not noticing rolloff till 40 hz or so, you're doing pretty decent for what you've got... if you had a bit more extensive EQ in that HU, i'd suggest you could actually EQ in a bit more bass at low frequencies to improve it (like a small bump up in the 30 hz range), but i don't think the 9827 has much at all for EQ settings, so that's out of the picture. (actually, i know it doesn't, as that is what i put into the wife's Ody.)

 

Thanks for all the advice. I'm finding its a tough battle between sticking to a budget and satisfying the urge for better sound.

I played around with the limited EQ on the Alpine and a little bit of tuning seemed to help. I cranked the amp power up to around 75% and reduced the bass output of the head unit (-4 at 60Hz) and things are already sounding better. I popped in one of my favorite test cds, and ended up enjoying the rest of the album (Pink Floyd - Dark Side of the Moon). If you're familiar with the album, at what frequency are the "heartbeats"? With the new settings, I was impressed with the output and "cleanness" of the sub.

edit** - Looks like Floyd goes pretty low. Here's what I found:

-Pink Floyd's "Speak to Me" (Track 1 "heartbeat")
(27Hz. at 14.1dB below maximum digital record level,

- Thomp

 

*nods*

familiar w/ the CD (enough to know what you're talking about).

sounds like a good solution. sounds like you've pulled the bass out of the doors, and relocated it to the sub. where is the sub crossed over? make sure it's notably above 60 hz so that you don't get a dropout of frequencies in the 80-120 hz area. crossing it (sub) over high will make the source of the bass a bit more noticable, but it offloads the bass requirements of the mid drivers.


also -- keep in mind that your ear looses sensitivity for very high and very low frequencies...

btw -- yes, it's easy to get wrapped up in the quest for better sound, and in the process spend a ton of money. that's why we commonly ask for a budget up front...