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slim j
11-29-2005, 06:42 PM
I am looking into one of these DIY setups and I am thinking about active. I hear about it frequently but I am unsure what all is involved? Is it it just running a mid and a tweet off a 4 channel amp? ie a tweet to the front 2 and mids to the rear?
Does impendance matter very much becuase I see many of the DIY setups have 6 or 8 ohms.

I am going with the Kenwood X889 so I have many tuning features in my HU. I have a 4 channel amp that does 4x50@4ohms.

alphakenny1
11-29-2005, 06:46 PM
yea pretty much with what you said but also you get to choose your crossover pts and slopes as well. much more flexbility in tuning than a passive setup where the crossover pts and slopes are already determined for you.

slim j
11-29-2005, 06:50 PM
So you need an crossover?

alphakenny1
11-29-2005, 06:57 PM
i just did a quick search on your HU and it seems (don't for know sure) that it doesn't have a crossover that will support a 2 way frontstage, so then yes you probably need a external crossover.

slim j
11-29-2005, 06:59 PM
So the tuning is done by the headunit and not the amp?

squeak9798
11-29-2005, 07:03 PM
So the tuning is done by the headunit and not the amp?

For an active setup, the "tuning" is done anywhere prior to amplification of the signal. This can be done in the headunit, with an external active crossover or with the amplifier's crossovers, or any combination thereof......whatever allows you to get the crossover frequencies and slopes you need.


Also, impedance does not matter as long as your amplifier can supply ample power at that impedance.

slim j
11-29-2005, 07:07 PM
So basically...If I purchased Seas L18RNX and 27TDFC, I just tune each one with combination of HU and amp until it sounds good....this seems easy enough, but time consuming.

Is the 27TDFC okay for IB setups in doors?

squeak9798
11-29-2005, 07:11 PM
So basically...If I purchased Seas L18RNX and 27TDFC, I just tune each one with combination of HU and amp until it sounds good....this seems easy enough, but time consuming.

It's not *that* easy.

You will need the ability to bandpass the mid and highpass the tweeter. Not only that, but you will need to be able to select appropriate crossover points and having variable slopes never hurts.

It all depends on the crossover frequencies your crossovers will allow and if you have enough crossovers to be able to properly bandpass the mid.


Is the 27TDFC okay for IB setups in doors?

That's a tweeter. You can't IB a tweeter.

But yes, the L18 should be fine in your doors.

slim j
11-29-2005, 07:16 PM
It's not *that* easy.

You will need the ability to bandpass the mid and highpass the tweeter. Not only that, but you will need to be able to select appropriate crossover points and having variable slopes never hurts.

It all depends on the crossover frequencies your crossovers will allow and if you have enough crossovers to be able to properly bandpass the mid.


What should I search for in look for a tutorial on how to do this? What is bandpass? I am only familiar with high pass and low pass. My amp doesn't have that option.



That's a tweeter. You can't IB a tweeter.

But yes, the L18 should be fine in your doors.


Sorry, I got them backwards...:)

alphakenny1
11-29-2005, 07:22 PM
bandpass is basically a HP and LP to a certain speaker. As of right now i have my mids HP at 63hz with 12db/slope and LP at 1.25kz with 12db/slope. So basically its bandpassed at 63hz and 1.25kz.

3.5Max6spd
11-29-2005, 07:49 PM
Your Hu doesnt support an active fronstage...so no, it doesnt have much for tuning....

You need to Highpass your tweeters above the 200hz the Kenwood xovers limit/permit you...more like generally ~2Khz +/- area

You need to band pass your midbass. Between the HP of the HU say 80hz for example, you then need to Lowpass the other end up to where your tweeters pick up....hopefully you have an amplifier with decent adjustable xovers that'll let you set them that high

squeak9798
11-29-2005, 07:51 PM
Get one of these and you'll be good to go: http://search.ebay.com/search/search.dll?cgiurl=http%3A%2F%2Fcgi.ebay.com%2Fws%2 F&fkr=1&from=R8&satitle=Coustic+XM6&category0=

slim j
11-29-2005, 10:39 PM
so bandpass is roughly equivalent to a interest rate collar (all I do is study derivatives). Ie has upper and lower bounds/frequencies...which makes sense.

What type of head units support a front active stage?

alphakenny1
11-29-2005, 10:42 PM
Yes. as for HUs that support an active front stage off the top of my head the Eclipse 8455, Pioneer 860, Alpine 9835 and 9855, Clarion DRZ9255. I'm sure theres more though.

slim j
11-29-2005, 10:43 PM
Do they say specifically supports active front stage or is there something I should look for?

alphakenny1
11-29-2005, 10:47 PM
well you should for if it says "3 way crossover." if it says something like that then yes that HU will support an active front stage.

ngsm13
11-29-2005, 10:52 PM
Get one of these and you'll be good to go: http://search.ebay.com/search/search.dll?cgiurl=http%3A%2F%2Fcgi.ebay.com%2Fws%2 F&fkr=1&from=R8&satitle=Coustic+XM6&category0=

I don't know why people keep recommending them...they **** ***. They garbage, and never work. Mine came completely DOA, Jason's came with one section DOA, and finally when it came back...it ******...***.

Just an observation.

If you are so infamiliar with all this ****, you should probably consider a Regular passive component set FIRST. Then work torward an active. There are A LOT of things that can go wrong with an active setup, and if you're not sure of what you're doing...it can sound like ****.

NG

slim j
11-29-2005, 10:59 PM
I feel as if I am color blind and am trying to see color. I hear on this forum about "color" but I have no idea what it means or if I am already seeing it but not recognizing it. I think what I have sounds okay but could be better. All i have is bass and words. I am thinking there must be something in between and I am trying to see what's there.

I also like the idea of doing it myself and knowing what is going on. I am not rich or anything but I have enough funds to break some stuff if I learn. I have also been watchingh people's sigs to see what they are running but I don't know much about the setup, just what they are running.

ngsm13
11-29-2005, 11:05 PM
Well, just as a reference...here's my active setup:

-Alpine 9835 HU running 3-way active
-RE Audio 15 MT
Lowpassed 50hz, 24dB/oct slope
-RE Audio XXX6.5
Highpassed @63hz, 24dB/oct slope
Lowpassed @2kHz, 24dB/oct slope
-Vifa 1" Neodymium Textile Dome Tweeter
Highpassed @2.5kHz, 24dB/oct slope
-Kicker 450.2, 200rms x 2 for mids
-Kicker 200.2 ~30rm x 2 for tweets
-Incriminator Audio 20.1 @.35ohm daily for MT

I recommend getting a HU that has a built in crossover capable of running your setup. Alpine is my preference, Eclipse 8--- series are great as well.

NG

slim j
11-29-2005, 11:11 PM
I never thought of 3 ways as like that. I always thought it was more like a 6.5, 4, and a tweet.

joeboxer5876
11-29-2005, 11:13 PM
is there an advantage to using a nice crossover like an audio control vs. using the crossovers on the alpine 9835 HU.

alphakenny1
11-29-2005, 11:16 PM
I never thought of 3 ways as like that. I always thought it was more like a 6.5, 4, and a tweet.

what you are refering to is a 3 way front stage. i have a 3 way setup as well. i have sub (low), 2 mids (mids) and 2 tweets (highs). 3 ways right?

slim j
11-29-2005, 11:20 PM
Is there significant advantages to a 3 way front stage? Nevermind for me since I only have 4 channels and don't want to use a crossover.

ngsm13
11-29-2005, 11:21 PM
is there an advantage to using a nice crossover like an audio control vs. using the crossovers on the alpine 9835 HU.

IMHO, the only thing that would be better from AC would be the DXS or whatever that digital crossover is. All their other **** like the 3xs, 4xs, etc...is inferior and harder to use.

NGs

alphakenny1
11-29-2005, 11:23 PM
Is there significant advantages to a 3 way front stage? Nevermind for me since I only have 4 channels and don't want to use a crossover.

after reading all this i think you should just buy a component set and go with a passive setup. just my suggestion.

ngsm13
11-29-2005, 11:26 PM
after reading all this i think you should just buy a component set and go with a passive setup. just my suggestion.

Agreed.

NG

3.5Max6spd
11-29-2005, 11:29 PM
I never thought of 3 ways as like that. I always thought it was more like a 6.5, 4, and a tweet.

Add a sub ...that makes it 4ways...4 sets of chs needed to control each pair of drivers

3way active fronstage + sub = 4way active

slim j
11-29-2005, 11:34 PM
I'll figure it out somehow...thanks for your help anyways.

alphakenny1
11-29-2005, 11:43 PM
yea it's not actually not that bad. It's like learning derivatives and integrals. When you first look at it, your like "WTF is this?!?!" but after reading a lil bit doing derivatives and integrals were hella easy. just read and read.

joeboxer5876
11-29-2005, 11:45 PM
what makes an external crossover like the digital AC better than the HU crossovers?

slim j
11-29-2005, 11:46 PM
Well there is quite a difference.I can read Security Analysis by Benjamin Graham (warren buffet's teacher) but I haven't found many books on this subject. If you know of a few good ones, I would be glad to read up.

slim j
11-29-2005, 11:47 PM
I mean financial derivatives, not calculus...no money in silly math, lots of money in options, futures, forwards, etc. I am a finance man.

alphakenny1
11-29-2005, 11:51 PM
what makes an external crossover like the digital AC better than the HU crossovers?

the only reason i could think of that might make an external xover better than an HU crossover is that the external xover might offer steeper slopes. I prefer an HU because it is at the tip of your hands. Unless of course you have a H701 with the remote control, etc.

slim j
11-30-2005, 01:55 AM
I actually found a 3-way setup that may work. Here is what I discovered during my brief research:

RS180 -- 40-2,200 Hz
DC50F -- 500-6,000Hz
RS28 -- 1600-20,000Hz

Total cost is roughly $214.50.

Which is pretty good. Now the only problem is how to power them. I can get that crossover which squeak mentioned but I heard bad things about it here as well as on the diyaudio.com forum (quite quite helpful btw). I have 4x50 currently and can do 2x200 bridged (4 ohms).

Should I try and find (or have someone build) a 3 way crossover? Use the coustic anyway?

slim j
11-30-2005, 02:12 AM
Update...I figure I can run the RS180 off the amp and have no problems...just keep it under 1k.

Is there any passive crossover that allows the mid to be played between say... 900 - 3000 hz and tweeter from 3000 up?

I am not sure if these frequencies should be tuned to music I listen to or the drivers themselves.

Thanks.

Speedyd718
11-30-2005, 11:07 AM
why do u wanna use a midrange, with that large format tweet? the dayton tweet can play down to the 1800hz range and the mid can pick up there too. i'm gettin ready to do an active setup btw. just run the dayton mid and tweet, and get an amp for each (love my zap's). then get an eclipse 8455 and you're ready to go, install.

Dave

ngsm13
11-30-2005, 01:48 PM
why do u wanna use a midrange, with that large format tweet? the dayton tweet can play down to the 1800hz range and the mid can pick up there too. i'm gettin ready to do an active setup btw. just run the dayton mid and tweet, and get an amp for each (love my zap's). then get an eclipse 8455 and you're ready to go, install.

Dave

x 2...

;)

NG

slim j
11-30-2005, 02:05 PM
excellent point, which proves my level of novice. If I go with the eclipse, do I still need 2 amps or will one 4 channel work?

amr952
11-30-2005, 02:14 PM
One 4 channel will work just fine, that is what I am using. Good luck.

Andrew

slim j
11-30-2005, 02:15 PM
Where do you buy that CD Player?

amr952
11-30-2005, 02:18 PM
This is Eclipse's website. Eclipse. (http://www.eclipse-web.com/) Just go there and put in your address, and find a local retailer. You can buy off of ebay or forums if you need to save some money. But the best option is to buy from a dealer and have them install it, then you get a 3 year warranty, and a 1 year theft warranty.

Andrew

slim j
11-30-2005, 02:19 PM
What else has the active crossover capability but works with XM. Otherwise...the eclipse would be a good bet.

Speedyd718
11-30-2005, 02:28 PM
pioneer 860/960 use xm if u really need xm but i'd take the eclipse over the pioneer. i had both at the same time and decided on the eclipse. better sound produced and way better eq option(when active u get 5parametric eq bands each for the mid input and tweet input. that's 10 total).

amr952
11-30-2005, 02:38 PM
x2 on the Eclipse 8455, much better then the pioneer imo. Another option that you may want to check out is the Alpine 9835, that is a great deck also that can do what you want.

slim j
11-30-2005, 03:28 PM
x2 on the Eclipse 8455, much better then the pioneer imo. Another option that you may want to check out is the Alpine 9835, that is a great deck also that can do what you want.


If I can sell this pioneer xm to a friend, cancel xm and get with sirus. I think they are about the same deal anyway.

Does the 8V preout hurt? I would assume it is adjustable, but can you adjust each channel? My diamond audio says it will clip with such high voltage. My sub amp can take up to 6V

Speedyd718
11-30-2005, 03:41 PM
8v shouldn't hurt, definitely helps cancel extra noise(whines and such). always had whines with my other decks. not so with the eclipse. no preout voltage is adjustable though, it's set in the deck.

slim j
11-30-2005, 04:00 PM
I don't know...the amp manual said it would be too much. Looks like I am stuck with the pioneer.

amr952
11-30-2005, 04:21 PM
You will be fine with the Eclipse, the 8V will not hurt anything. You will very rarely get the 8V out of it anyways, only at close to full volume.

squeak9798
12-01-2005, 10:08 AM
8v shouldn't hurt, definitely helps cancel extra noise(whines and such). always had whines with my other decks. not so with the eclipse. no preout voltage is adjustable though, it's set in the deck.

That's funny.....I got alternator whine when I installed my Eclipse 8053 ;) And to make it even funnier....I uninstalled a rated 2V deck that had zero alt whine :D

Preout voltage doesn't affect alternator whine as that's primarily a function of the grounding (voltage potential differences) and not the preout voltage.




And preout voltage is adjustable.....with the volume knob :)

squeak9798
12-01-2005, 10:10 AM
I don't know...the amp manual said it would be too much. Looks like I am stuck with the pioneer.

Remember that you'll only ever get rated preout voltage out of the deck with a 0db test tone at full volume. With music, which is typically recorded at -6db (sometimes even -10db), you're looking at an average of ~2V output at maximum volume.


I'm presently running my Eclipse 8053 (8V outputs) into amplifiers rated to accept a maximum input voltage of 1.5V......and I do not believe I've ever maxed out the input stage.

ngsm13
12-01-2005, 12:35 PM
x2 on the Eclipse 8455, much better then the pioneer imo. Another option that you may want to check out is the Alpine 9835, that is a great deck also that can do what you want.

Exactly, the Alpine 9835 is XM ready as well. I use the 9835 and LOVE it.

NG

slim j
12-01-2005, 12:56 PM
Too bad it is not available new or I would most definitely go with the alpine. Do they have any "problems" like the pioneer had RCA problems and problems with the 960s ribbon breaking.

Speedyd718
12-01-2005, 02:34 PM
That's funny.....I got alternator whine when I installed my Eclipse 8053 ;) And to make it even funnier....I uninstalled a rated 2V deck that had zero alt whine :D

Preout voltage doesn't affect alternator whine as that's primarily a function of the grounding (voltage potential differences) and not the preout voltage.




And preout voltage is adjustable.....with the volume knob :)

hmm, i've had a jvc sh707, and pioneer 740 and 960. and i had alt whine all of those. i had to install noise cancelers to rid it. but with the eclipse i got no whine(maybe because the zapco balanced symblink helps though:naughty: )<<<---just thought of that while typing, LOL. thanks for clearing the preout volt adjust thing though. i never thought about it that way.