Tons of sq based questions....

[martiandancer31 10+ year member]

correct. get two great midbass drivers. they should play from 60Hz - 5kHz. get two good tweeters. they should play from 2kHz - 25kHz. your final crossover point will be between 3-5kHz.
you don't need to buy a complete component set if you can run active. you can buy individual drivers. some of us rely on Madisound and Parts Express for raw drivers.

this. My front stage is mainly oriented towards SQ, and I essentially went to PE and found drivers that did what I wanted them to do within my price range. I went with 1" metal dome tweeters because I like the sound of metal domes and I want to cross at around 2.5k. That's a little low but the 1" tweeters should handle it at the volumes I will use them at. I also looked at things such as the voice coil size, power handling, and efficiency - drivers that are more efficient (obviously) require less power to generate more sound, but a secondary and not-so-obvious benefit to this is less power compression which equates to more linearity and better overall sound. Another thing to look at is the off-axis frequency response. Woofers (and other speakers, but whatever) tend to get more directional as you go up in frequency, which (besides inductance) is why you don't typically see them crossed higher than 5k-ish. Assuming your tweeters are in your a-pillars and your woofers are in your doors, you're going to be more off-axis from your woofers than your tweeters which can cause some interesting things around your crossover frequency. Low inductance woofers tend to perform better at higher frequencies,but not necessarily off-axis. Just generally. They also tend to have less group delay although that can depend on alignment. Also, i'd definitely over-power both your woofers and tweeters. Headroom, my friend. They can handle short bursts of lots of power as long as it's clean.

These are just some things that popped into my head in no particular order whatsoever.

Lastly, BUY A SOUND PROCESSOR. No matter what drivers you buy, the inside of a car is a crappy place to try to achieve a reasonable frequency response. I'd suggest a unit like the alpine pxe-h660. It uses audessey multieq XT and allows you to actively cross your front stage, which you should definitely do. Audessey is also one of if not THE most proven type of processing. A lot of people complain about it because "they can't select their own eq curves" or whatever, but in reality, that's NOT what the device is INTENDED for. It's intended to give you a bassline EQ to work with, as well as excellent time alignment. Audessey can make corrections in both the frequency and time domain, which is not something you can do with, say, a 31-band graphic eq. Then, on your HU, you can generate custom EQ curves, and you know that that's whats coming out of the speakers because you already have a good bassline EQ.

I'm not saying that you can just go to PE and buy the most expensive 6.5" woofer and the nicest tweeter they have, hook them up to the processor, press the calibrate button, and call it a day. It's not that easy. But using the processor to help get a baseline eq is a great way to get started. To really understand what's going on with your frequency response, you need to invest in a calibrated microphone and measure. Measure, adjust, etc. Recalibrate. See what I mean?¿

Soundproof your car. You want to hear jimmy page plucking away during the quiet parts of stairway to heaven? You better have a really quiet car or be prepared to turn your stuff up really loud.

Sorry if this sounded like rambling d00d. Hope some of it helps.

 

[keep_hope_alive Premium Member]

^agreed.

in the two hours between posts on here, i was in my garage with an RTA and measurement mic. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

i'm always tweaking, always experimenting, always learning.

 

[Why So Cereal? 5,000+ posts]

I've also found that time delay between speakers (front stage) helps to make your midbass more present.

 

[disturbed471985 5,000+ posts]

Flutes for the win!!!!

 

[Joseph7195 10+ year member]

Subscribed for info and hopefully some build pics too.....//content.invisioncic.com/y282845/emoticons/up2something.gif.dd110ecf3ae4b76050d87598f2f8de7c.gif

 

[Falcons 5,000+ posts]

Man this thread is doing great. Thanks for the info Martian. Big help and I read it all. I was looking at some image dynamics as stated on the first page. On sonic electronic they are 300 a pair, now I know there are better speakers to be had at a lower price am I right?

 

[keep_hope_alive Premium Member]

I've also found that time delay between speakers (front stage) helps to make your midbass more present.

true, but you need your front stage to reproduce midbass accurately first. you'll localize based on arrival times (and IID, ITD, HTRF, ITDG, etc.) so if you can control arrival times and you have enough midbass, you can place your bass in the sound stage. it's pretty cool once you achieve it. crossover points/slopes play a role here.

in order to get my bass comfortably located in my sound stage, i had to run my kick 4" mids down to 160Hz and my door 6.5" midbass down to 60Hz.

 

[Falcons 5,000+ posts]

So I shouldn't even worry about my back deck right? Just fillers and a waste of time? And how exactly do you set the timing of the bass response?

 

[martiandancer31 10+ year member]

Man this thread is doing great. Thanks for the info Martian. Big help and I read it all. I was looking at some image dynamics as stated on the first page. On sonic electronic they are 300 a pair, now I know there are better speakers to be had at a lower price am I right?

it's possible, but remember that if you're buying raw drivers you need to either design a passive xover (don't do this) or use an active xover (do this). A lot of processors will have active x-over capabilities built-in (some head units too) so this shouldn't be an issue.

It depends on what your application is too. Again, assuming doors, you can go a couple different ways - if you build pods for the speakers, you're going to want a driver with a lower VAS and probably a lower qts as well. If the door is the box for the speaker, you're probably going to want something with a higher VAS and a qts higher than .4. Regardless of airspace, you probably want something with decent xmax, low inductance, good sensitivity, a decent size voice coil, etc, and those things can cost money.

for example, i really, really wanted to use this driver :Tang Band W6-1721 6-1/2" Underhung Midbass Driver it's an excellent driver, sensitivity is a tad low but not bad for a 6.5" midbass driver. Other than that the parameters are excellent and the frequency response (on-axis, anyways) is fantastic. The reason I didn't was because i wouldn't be able to lower my windows - the magnet is too large and would be in the way. I ended up going with this driver ( Peerless 831735 6-1/2" HDS Driver ). Sensitivity is lower than I wanted but nothing's perfect. The price is right and that was all the convincing I needed //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[martiandancer31 10+ year member]

So I shouldn't even worry about my back deck right? Just fillers and a waste of time?

in all likelihood the back deck will do nothing but muddy up your sound. If you want the best SQ i wouldn't use it.

 

[Falcons 5,000+ posts]

alright so it looks like i need to get some measuring done lol. i got a lot of room in my doors for some reason so i shouldnt have a problem. and my deck has a xover that i can use so it should work out pretty good.