Ahoy hoy all!

[M249SAW]

My first post in the Audio section. Just like to get some opinions on the setup I am currently compiling. My overall goal is Sound Quality. I already have the Head unit and front components sitting on my dresser, the rest are planned parts.

Car: 2007 Hyundai Accent 3rd Hatchback
Head unit: Alpine CDA9857
Front Components : Polk dB6500 6.5" (only separate I could find that would fit)
Rears: 6x8" im not going to power for better imaging
Amp: Rockford P450.4 60w x 4 (front to components rear bridged 220w to sub)
Sub: Single Polk/Momo 10" sub in sealed enclosure.

Things Im wondering about:

Rockford amp had a pretty low S/N ratio 80db and high THD 1%
Alpine has only a 2V preout (audiocontrol line driver maybe?)
Not alot of room in hatch (Im a firefighter so I usually have my bunker gear in the back which takes up alot of space) Downside to having a hatchback but I love the gas mileage with all the driving I do. So Im even entertaining the idea of an 8" subwoofer.

Thanks for the input. I plan on attending the next meet in September.

Kyle

[Notladstyle]

That S/N ratio & THD are really bad and will hurt your clarity and definition on highs especially if you will be driving only one set of components - You will notice it. Same for the 2v output - but this will be much less noticeable.

In my opinion, you will need somthing a little more substantial amp wise if it is going to be the center block of your audio system. Perhaps a Polk 400.4 or a JL 300.4. They are a bit more pricey, but better to do it right the first time than to wind up like me rebuilding your system every two weeks. Just kidding, I go at least a month.

C400.4 (4/3/2 Channels) Amplifier from Polk Audio (http://www.polkaudio.com/caraudio/products/c400_4/)
JL Audio: Products (http://mobile.jlaudio.com/products_amps.php?amp_id=254)

JL amps have actually become my favorite because of their flexibility - Regardless of the ohm load you present their regulated output is the same.


If you have a small space that a standard cubical box would not fit (such as wheel well spaces), I would suggest you fabricate a fiberglass enclosure to fit that area and keep the prime real estate for your other goods.

Again, in my opinion, you wont get natural sounded low end response from a single 8" woofer. You will need at least a 10.

Welcome to AHQ, look forward to seeing you at the meet.

Dalton

[Miles]

the thd is a byproduct of the new ces rating system... you can claim any power you want as long as it's less than (or equal to) 1% thd. in car, at normal listening volumes, it's generally a lot lower. rockford i believe claims .08%?

i believe the s/n ratio has something to do with the ces ratings as well, but i'm not too sure.

edit: also, that jl amp would be a big cut in power to the sub... 150 watts of regulated power.

[M249SAW]

Yes I would like to do it right the first time. I looked at the Polk 400.4 it looked like a good amp, but am I setting myself up for failure with a one amp system?

Looking at that each component side would get 100w with 200w to the sub (10" Momo sub is rated at 200w RMS).

So if that would correct the inferior amp design problem who would I alleviate the 2v output? Audiocontrol Overdive and bump it to 8v? The amp would probably be under/behind the drivers seat or on the back of the fold down seat, so not a real long distance for the interconnects.

I thought about a custom enclosure, in fact you mentioned building one in your email Dalton. The 10" takes up .66cu/ft so not too much. Perhaps when I get you out for the headunit/component/amp install we can go over that.

Thanks
Kyle

[M249SAW]

Also peoples opinions on buying car audio off of Ebay vs and Authorized dealer?

[TJElite]

the thd is a byproduct of the new ces rating system... you can claim any power you want as long as it's less than (or equal to) 1% thd. in car, at normal listening volumes, it's generally a lot lower. rockford i believe claims .08%?

i believe the s/n ratio has something to do with the ces ratings as well, but i'm not too sure.

edit: also, that jl amp would be a big cut in power to the sub... 150 watts of regulated power.

Miles is correct...the 1% is part of the new CES rating system. It doesn't actually say that it will have that much, it just can't have more than that, at rated power. FWIW, 1% is still not much of a number. I wouldn't be concerned about the SN either.

Toby

[TJElite]

Yes I would like to do it right the first time. I looked at the Polk 400.4 it looked like a good amp, but am I setting myself up for failure with a one amp system?

Looking at that each component side would get 100w with 200w to the sub (10" Momo sub is rated at 200w RMS).

So if that would correct the inferior amp design problem who would I alleviate the 2v output? Audiocontrol Overdive and bump it to 8v? The amp would probably be under/behind the drivers seat or on the back of the fold down seat, so not a real long distance for the interconnects.

I thought about a custom enclosure, in fact you mentioned building one in your email Dalton. The 10" takes up .66cu/ft so not too much. Perhaps when I get you out for the headunit/component/amp install we can go over that.

Thanks
Kyle

More power is better than less power, but your setup will work. If you can only have one sub, I would probably buy one with more xmax and rms handling, and get a bigger amp, though.

Can't go wrong with some sort of line driver, and audiocontrol is a great choice. Even 5v decks can benefit from a line driver.

Toby

[TJElite]

Also peoples opinions on buying car audio off of Ebay vs and Authorized dealer?

Well, as an authorized dealer, I say no Ebay. Seriously, its a crap shoot. I've heard of people having no problem buying electronics off of ebay, and I've heard just as many who end up with bad stuff, and can't get any relief from the guy they bought it from. I do know that many of the manufacturers getting stiffer on refusing warranty service on products not bought from authorized dealers...even Audiobahn has started this. Also, some of the ebay stuff is B grade (refurb) and I've even seen some true grey market stuff...designed for sale in Japan. In addition to sometimes not having english instructions, they often don't have US tuners (japan and europe don't have the same FM bands).

So, its like Clint said...'Do you feel Lucky?'

Toby

Toby

[TJElite]

Oh, by the way. Thank you for being a Fire Fighter...

Toby

[M249SAW]

Oh, by the way. Thank you for being a Fire Fighter...

Toby


No Problem, my pleasure;)

[M249SAW]

So I looked again at the Polk 400.4 and it looks at it should serve the purposes intended. 75w to the front components and 200w to the 10" Momo sub (conservative numbers).

I really want to keep it as simple as possible and as stealth as possible.

[Notladstyle]

So I looked again at the Polk 400.4 and it looks at it should serve the purposes intended. 75w to the front components and 200w to the 10" Momo sub (conservative numbers).

I really want to keep it as simple as possible and as stealth as possible.


I think the 400.4 will serve your purpose. If you want to upgrade later you can always grab another amp to drive the sub and bridge the 400.4 to the mids... But im pretty sure you will be satisfied with your current plan.

[TBSpyder]

An 8 can sound pretty good, depending on the enclosure and sub you go with. I've done the JL w0 and w3's down in the foot well on the passenger side and it sounds damn good...granted, not you can't expect it to be rattling your eardrums, but it can fill in your low end nicely.

[Notladstyle]

An 8 can sound pretty good, depending on the enclosure and sub you go with. I've done the JL w0 and w3's down in the foot well on the passenger side and it sounds damn good...granted, not you can't expect it to be rattling your eardrums, but it can fill in your low end nicely.

Very true. But besides the JL I dont hold 8" woofers very highly. The JL's cost is so far above a comperable 10" that unless theres absolutely nowhere to get the 10 in, its not worth it.

[TBSpyder]

Very true. But besides the JL I dont hold 8" woofers very highly. The JL's cost is so far above a comperable 10" that unless theres absolutely nowhere to get the 10 in, its not worth it.

It's worth with when you consider you can fit the entire thing in the passenger foot well...sacrificing only about 8" of leg room....leaving your entire trunk to do whatever you please with. Besides the fact that everything is completley stealth and it brings your sound stage more towards the front like it should be.

[M249SAW]

It's worth with when you consider you can fit the entire thing in the passenger foot well...sacrificing only about 8" of leg room....leaving your entire trunk to do whatever you please with. Besides the fact that everything is completley stealth and it brings your sound stage more towards the front like it should be.

Hmm interesting idea, Ive seen it done before in magazines. Dalton, possible?

[TJElite]

I've done two systems with the Crossfire DB38, and they have both sounded very good. .25-.5 cubes. I sell it for $75

Depending on your footwell design, and how much you can give up, it can be easy to do. Worst case, you might have to cut the floor, and build the box outside the car.

Toby

[M249SAW]

Ill be at the next meet Toby Ill go over it with you there. Also Ive been looking at the Crossfire Amps, how do they stack up against the others?

[TJElite]

Ill be at the next meet Toby Ill go over it with you there. Also Ive been looking at the Crossfire Amps, how do they stack up against the others?

I really like them. When I opened up, I could have had basically any lines I wanted. I started with Audiobahn, Rockford / Lightning, and Crossfire. Crossfire is basically all I sell, now. The put out lots of power, and are very clean. The new XP series comes with a SEVEN YEAR WARRANTY!! I'd put them up against any other amp on the market, watt for watt. They also have an entry level line, called Distinct Audio, that just can't be beat for the money, in my opinion.

Toby

[TBSpyder]

Hmm interesting idea, Ive seen it done before in magazines. Dalton, possible?

I did them with a fiberglass rear and an angled mdf front. Flush mounted the sub and carpeted over the entire thing in the factory color, this way you can still even put your feet on it without worrying about it getting kicked it....plus, there was no way you could tell there was a sub there, it would look completley stock.

[Notladstyle]

An 8" woofer will produce directional bass - I dont think it would sound good with only one side. But yes totally possible to build. I wouldnt cut the footwell to fit the enclosure though.

[TJElite]

directionality is primarily due to frequency...the size of the woofer doesn't matter.

Toby

[Notladstyle]

directionality is primarily due to frequency...the size of the woofer doesn't matter.

Toby


I just dont get the feeling a single 8" combined with a single set of components - even with rear fill - would be a satisfactory system. Unless it has an exceptional amount of airspace and possibly a decent tuned box which wouldnt be very easy to manage without taking too much space in the footwell or cutting the floorboard as you suggested earlier.

For a customer that is willing to experiment and doesnt mind a few follow up sessions to tweak and mod, I would say go for it and see what happends but for someone who wants everything to be set and go, done the first time, and be an all in one deal - its not worth the gamble when a 10 in the back is a sure fire thing.

[TJElite]

I can't disagree that a 10 would be better than an 8, all other things being equal, but you can base a system around an 8...

We did a 76 280z with a single 8 in a sealed .35 cu ft enclosure and a pair of 5 1/4 coax's in custom kicks...that's it. The 8 got about 250 watts from the back half of a Lightning amp, and the coaxes got 40 watts each. While it wasn't earth shaking, it sounded very good. Many people who heard it thought there were at least 2 10's in it.

We also did a new mustang (pics on my site) with the same 8, getting 150 watts from a 5 channel crossfire. The other 4 give 50x4 to 4 6 1/2's. Again, it was not a big boomer, but sounded very good. This 8 was also in a sealed box, about .4 cu ft.

Neither of these used any eq at all, and both were set up once, and have not been back, and both customers are very happy.

Small systems like these can be made to sound very good, but things like speaker placement become critical. One of the nice things about them, though, is that they are simple...fewer phasing problems, no need for big power wire, less to go wrong, etc.



Toby

[TBSpyder]

An 8" woofer will produce directional bass - I dont think it would sound good with only one side.

I've personally done that exact setup in several Miatas, 911/936's, Z3's, and a BMW 8-series. Almost all owners were very high-end audio enthusiasts and were very happy, if not blown away. No offense, but I'd even wager a couple of those cars were louder than yours. ;)

[Notladstyle]

I've personally done that exact setup in several Miatas, 911/936's, Z3's, and a BMW 8-series. Almost all owners were very high-end audio enthusiasts and were very happy, if not blown away. No offense, but I'd even wager a couple of those cars were louder than yours. ;)


=/ ill take that bet.