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michaelsil1
05-16-2007, 06:20 PM
I've decided to go with Active Crossovers. I'm having problems dialing in the sound I want. It was suggested that I get another Passive Crossover (I don't think so). The question is what Active do I buy? I'm running a two way 6.5". I can use all the help I can get.:confused:

crow
05-16-2007, 08:17 PM
You need to determine what you want to be able to control and how much you are willing to spend.

For a basic crossover unit, the Coustic XM6 is mentioned often as a nice budget crossover. I've seen them for $35 on ebay nib.

If you're looking to spend a bit more, Memphis 16-X03 is a nice looking piece. Arc Audio also makes a few crossovers. They make one in-dash unit that is really slick. They also sell a faceplate that combines the crossover with their in dash eq into a single dash panel which makes for a cool install. Audiocontrol is well known for their quality crossovers and processors.

Adjustability is another thing to check on. There are some units that use a resistor module that you plug into the board to set the crossover point. Some of the Audiocontrol units are set up that way. The modules are cheap and easy to make from a few parts from radio shack. Other units simply have a knob or switch to set the crossover point.

Beyond that, some of the newer head units will have built in crossovers that are fully capable of running a 3-way setup along with other system tweaks. There are also dedicated processors which either interface with a compatible head unit or run independently which allow you to set crossover points, time alignment, surround sound and so on. These can get expensive but it all depends on how much control you're after :greedy: :D .

MiniVanMan
05-17-2007, 12:44 AM
You need to determine what you want to be able to control and how much you are willing to spend.

For a basic crossover unit, the Coustic XM6 is mentioned often as a nice budget crossover. I've seen them for $35 on ebay nib.

If you're looking to spend a bit more, Memphis 16-X03 is a nice looking piece. Arc Audio also makes a few crossovers. They make one in-dash unit that is really slick. They also sell a faceplate that combines the crossover with their in dash eq into a single dash panel which makes for a cool install. Audiocontrol is well known for their quality crossovers and processors.

Adjustability is another thing to check on. There are some units that use a resistor module that you plug into the board to set the crossover point. Some of the Audiocontrol units are set up that way. The modules are cheap and easy to make from a few parts from radio shack. Other units simply have a knob or switch to set the crossover point.

Beyond that, some of the newer head units will have built in crossovers that are fully capable of running a 3-way setup along with other system tweaks. There are also dedicated processors which either interface with a compatible head unit or run independently which allow you to set crossover points, time alignment, surround sound and so on. These can get expensive but it all depends on how much control you're after :greedy: :D .

That's pretty dead on. Those are the two units that I recommend the most.

When looking for a crossover, just make sure it has the capability to low pass (for subs), bandpass (for mids), and high pass (for tweeters). You want the high pass and the low pass to be able to be adjusted between 1.5k and about 5 k. Give or take a few hz. Normal crossover points for 2-way component sets range from 2 khz to about 4 khz. This will give you enough room to mix and match components, and try different speakers.

The Memphis unit is very good, and can be found for a few dollars more than the Coustic. It's a bit easier to use, and generally just a bit better built. However, that's not a slam against the Coustic. If you look in my sig, I've ran a Coustic crossover, and have had very good success with it.

I wouldn't spend any more money than either of those until you get into units that have time alignment and built in EQ capability. The RF 360.2 comes to mind, and the AudioControl DQXS. PPI made a good one, if you can find one cheap called the DCX730. These units are all well into the hundreds of dollars. The AC unit can be found for around $400.00 on the low end (and doesn't have time alignement that I know of). At that point you're better off just getting a head unit that can do it all.

michaelsil1
05-17-2007, 12:02 PM
I like the fact that you say the Memphis 16-X03 is easier to use that's probably what I'll start with, youíre also saying I'll also need to run the Subwoofer through it as well? My head unit is the Pioneer Premier DEH-P880PRS. I've already spent more than I bargained on; this learning experience has been costly.

MiniVanMan
05-17-2007, 01:12 PM
The 880PRS has the ability to actively tune. It has all the feature you need, active crossovers, equalizers and time alignment. You don't need an additional unit.

Save your money.

Also, what speakers are you using?

michaelsil1
05-17-2007, 02:09 PM
The 880PRS has the ability to actively tune. It has all the feature you need, active crossovers, equalizers and time alignment. You don't need an additional unit.

Save your money.

Also, what speakers are you using?

MB Quart QSD 6.5", Focal TN 52 Tweeter, JL Audio W7 12 ProWedge Sub. Would I still need to run through the passive crossover?

chucku
05-17-2007, 04:08 PM
No, your hu has all the stuff you need built right in. Read the manual. You have to flip a switch on the side of the hu. Take it out of the dash and slide the case out of the chassis, youll see a switch called network, switch it to that and reset the unit. You will then find the tuning selection in the audio section. It takes awhile to tune the comps but in the end its worth it. Make shure the front rca go to the tweeter amp and the rear to the mid amp. If you screw that up, you risk sending the wrong signal to your tweets and can blow them.

michaelsil1
05-17-2007, 07:18 PM
Would I keep the amplifier high pass filter on for the mids and the tweeter?

DejaWiz
05-17-2007, 08:06 PM
Would I keep the amplifier high pass filter on for the mids and the tweeter?

Not if your using an active crossover, no.

///M5
05-20-2007, 12:22 PM
In the 880 you need to turn on what they call Network mode. It has better adjustability than either the Coustic or Memphis mentioned. Use your headunit and enjoy!!

michaelsil1
05-21-2007, 11:25 AM
I went active!:yumyum: I'm not going back.:cool:

DejaWiz
05-21-2007, 11:43 AM
I went active!:yumyum: I'm not going back.:cool:

Very awesome! Details please?

michaelsil1
05-21-2007, 02:57 PM
Very awesome! Details please?

I used my Head Units Active Crossover: Premier DEH-P880PRS.

MB Quart QSD 6.5" (two front, two rear)

Focal TN 52 Tweeters

JL Audio 12 W7 ProWedge Subwoofer

Crossover Points: Sub 63 Hz, Mid Bass 80Hz-3.15 KHz, Tweets 3.15 KHz

18db Slope accross the board, Subwoofer Reverse Phase.

Power: Rockford Fosgate (new) Power Series T1500-1bd,

Alpine PDX 4x150

:)

DejaWiz
05-21-2007, 02:59 PM
Crossover Points: Sub 63 Hz, Mid Bass 80Hz

Why the frequency gap?

dragnix
05-21-2007, 03:10 PM
because the frequency doesn't get cut at 63 or 80, but it just slopes down. So ur not losing any frequency in between because it will be played...by both speakers, i believe.

God i hope that makes sense

<-----at work :fyi:

xplicitACTS
05-21-2007, 03:13 PM
I have a couple of nice active xovers in my forsale thread.

http://www.caraudio.com/forum/showthread.php?t=235483

DejaWiz
05-21-2007, 03:37 PM
because the frequency doesn't get cut at 63 or 80, but it just slopes down. So ur not losing any frequency in between because it will be played...by both speakers, i believe.

God i hope that makes sense

<-----at work :fyi:

Yes, I know it slopes, but why have the slope start well before it should? At -18dB/Oct slope for both the sub and mid channels, why do this....

Sub:
63Hz = 0dB
80Hz = -11dB
126Hz = -18dB
252Hz = -36dB

Mid:
80Hz = 0dB
40Hz = -18dB
20Hz = -36dB


When you can do this.....

Sub:
80Hz = 0dB
160Hz = -18dB
320Hz = -36dB

Mid:
80Hz = 0dB
40Hz = -18dB
20Hz = -36dB

It's not going to be that exact since the slope starts a little before the set frequency, but I hope you get the picture.

Set the sub LP to 80Hz and the BP-HP to 80Hz.

That will (roughly) make it so there is only about -3dB at about 80Hz instead of -6dB at about 70Hz.

michaelsil1
05-21-2007, 03:42 PM
Why the frequency gap?

I started with the Sub @ 80 Hz the Mid Bass and Sub Bass didnít blend that well. I also tried @ 63 12db, where it's set now the Sub Bass and Mid Bass blend very well. I had to play for awhile for everything to meld.

DejaWiz
05-21-2007, 03:51 PM
I started with the Sub @ 80 Hz the Mid Bass and Sub Bass didnít blend that well. I also tried @ 63 12db, where it's set now the Sub Bass and Mid Bass blend very well. I had to play for awhile for everything to meld.

If it's set to where it's music to your ears, then right on. I suppose you can ignore my previous post then LOL.

michaelsil1
05-21-2007, 04:08 PM
If it's set to where it's music to your ears, then right on. I suppose you can ignore my previous post then LOL.

:eek: I have it set @ 63Hz 12db.:eek:

DejaWiz
05-21-2007, 04:17 PM
:eek: I have it set @ 63Hz 12db.:eek:

Yes, but in your previous post (http://www.caraudio.com/forum/showpost.php?p=3061651&postcount=13) you stated 18dB/Oct across the board. ;)


Even with a -12dB/Oct slope on the sub channel, the difference between a 63Hz setting vs an 80Hz setting is going to be about -3dB at 80Hz for the sub. No big deal, more of an FYI than anything else.

michaelsil1
05-21-2007, 05:29 PM
Yes, but in your previous post (http://www.caraudio.com/forum/showpost.php?p=3061651&postcount=13) you stated 18dB/Oct across the board. ;)

:confused: I made a Boo Boo!:crap:

Even with a -12dB/Oct slope on the sub channel, the difference between a 63Hz setting vs an 80Hz setting is going to be about -3dB at 80Hz for the sub. No big deal, more of an FYI than anything else.

I do have a concern: the frequency cut off for the 6.5" is 2.5 KHz the Tweeter is also 2.5 KHz. I do have both @ 3.15KHz 18db Slope. Should I be concerned?

DejaWiz
05-21-2007, 06:32 PM
I do have a concern: the frequency cut off for the 6.5" is 2.5 KHz the Tweeter is also 2.5 KHz. I do have both @ 3.15KHz 18db Slope. Should I be concerned?

If you aren't experiencing any roll-off, then I wouldn't be concerned.

michaelsil1
05-21-2007, 09:51 PM
Yes, but in your previous post (http://www.caraudio.com/forum/showpost.php?p=3061651&postcount=13) you stated 18dB/Oct across the board. ;)


Even with a -12dB/Oct slope on the sub channel, the difference between a 63Hz setting vs an 80Hz setting is going to be about -3dB at 80Hz for the sub. No big deal, more of an FYI than anything else.

Okay, I changed the Sub to 80Hz 18db and lowered the Level.:veryhapp:

It made a difference for the better.

Thanks for the help.:D

DejaWiz
05-21-2007, 10:26 PM
Okay, I changed the Sub to 80Hz 18db and lowered the Level.:veryhapp:

It made a difference for the better.

Thanks for the help.:D

Glad to hear it made a positive difference! ;)

michaelsil1
05-22-2007, 01:10 PM
Glad to hear it made a positive difference! ;)

I have to also admit there was a lot of operator error.:confused:

The Amps were out of Sync, Sub Amp was overpowering the main Amp; this became even more of an issue when I went Active. I read your how to set the Gains and ventured into the unknown (no Volt Meter), problem solved.

DejaWiz
05-22-2007, 01:17 PM
I have to also admit there was a lot of operator error.:confused:

The Amps were out of Sync, Sub Amp was overpowering the main Amp; this became even more of an issue when I went Active. I read your how to set the Gains and ventured into the unknown (no Volt Meter), problem solved.

Glad to hear that helped, as well. How satisfied are you with your system overall since you've gone active?

MiniVanMan
05-22-2007, 01:22 PM
Here's a link if you want to get an idea of what a midwoofer experiences in the upper range of it's frequency response. Actually, both the links I'll post might help you understand a bit better what's happening. However, what really matters is what sounds good to you.

http://www.diymobileaudio.com/forum/showthread.php?t=7107

http://www.diymobileaudio.com/forum/showthread.php?t=7160

michaelsil1
05-22-2007, 01:36 PM
Glad to hear that helped, as well. How satisfied are you with your system overall since you've gone active?

That's a very difficult question for me answer.


I'm glad I went Active it cured some of my main issues, overall I feel the system still lacks in the Midrange. I have very good Mid Bass, very good Sub Bass, so so Mids, okay Highs.

I might be to picky, however I'm on a mission: Great SQ!!:laugh

DejaWiz
05-22-2007, 01:38 PM
That's a very difficult question for me answer.


I'm glad I went Active it cured some of my main issues, overall I feel the system still lacks in the Midrange. I have very good Mid Bass, very good Sub Bass, so so Mids, okay Highs.

I might be to picky, however I'm on a mission: Great SQ!! :laugh:

One can never be too picky when it comes to getting great SQ. ;)

michaelsil1
05-22-2007, 01:57 PM
One can never be too picky when it comes to getting great SQ. ;)

:cool: Thanks.:cool:

michaelsil1
05-22-2007, 01:59 PM
Here's a link if you want to get an idea of what a midwoofer experiences in the upper range of it's frequency response. Actually, both the links I'll post might help you understand a bit better what's happening. However, what really matters is what sounds good to you.

http://www.diymobileaudio.com/forum/showthread.php?t=7107

http://www.diymobileaudio.com/forum/showthread.php?t=7160

Thank you,

This is going to take time to sink in.:eek:

michaelsil1
05-23-2007, 03:11 PM
Here's a link if you want to get an idea of what a midwoofer experiences in the upper range of it's frequency response. Actually, both the links I'll post might help you understand a bit better what's happening. However, what really matters is what sounds good to you.

http://www.diymobileaudio.com/forum/showthread.php?t=7107

http://www.diymobileaudio.com/forum/showthread.php?t=7160


Mini,

I read the threads.

What would you suggest I set the crossovers at?

Both the 6.5" and the Tweeter cut off at 2.5 kHz.

Using the formula 2 x 2.5= 5 kHz for the Tweeter creates a very large gap between the Tweeter and the Mid Ranges capacity.

Your calculator is probably better than my brain. :laugh:

MiniVanMan
05-23-2007, 03:34 PM
It think you misread. You need to know the Fs (Resonant Frequency) of the tweeters. If the Fs is 2.5 kz, it should still be useable to about 4k with a 24 db slope. Maybe even lower. The Fs of a standard car audio tweeter is about 1.5k to about 2 k. Some tweeters even have a much lower Fs like the Seas Neo I mentioned. Generally the more expensive the tweeter, the lower it will play. Manufacturers understand the off-axis alignment that comes with car audio, so your top end component sets will have tweeters capable of much lower crossover points. To get that kind of capability out of a tweeter is hard, and therefore expensive. The Seas Neo is the exception and why it is such a popular tweeter.

Now, don't get all caught up in the numbers. The true test is what sounds good. Driving a tweeter to it's Fs is pretty hard on it, and you're power handling decreases dramatically. If you're getting harshness out of the tweeter in the lower range of it's frequency response, then bump the crossover point up a bit. If there's a huge gap between it and the mid, then bump the mid up a bit.

One of the advantages of going active is being able to design a system to your specifications, using raw drivers that meet the harsh needs of car audio, while also being inexpensive.

DejaWiz
05-23-2007, 03:47 PM
Mini, props to you for your explanations here and in the links you posted.

michaelsil1
05-23-2007, 05:04 PM
Mini, props to you for your explanations here and in the links you posted.

Kudos! :thumbsup:

MiniVanMan
05-23-2007, 07:19 PM
Mini, props to you for your explanations here and in the links you posted.

Thank you.

Somehow managed to not offend anybody in this one. I need to stay away from those 8 ohm threads. :suicide:

DejaWiz
05-23-2007, 07:22 PM
LOL, nah.... keep schooling them.

michaelsil1
05-24-2007, 12:36 PM
One of the advantages of going active is being able to design a system to your specifications, using raw drivers that meet the harsh needs of car audio, while also being inexpensive.

This learning experience hasn't been inexpensive.

MiniVanMan
05-24-2007, 01:10 PM
It never is. There are ways to mitigating that cost, and you're on the right track now. Since you've taken the plunge to active. Take a look at DIYMobileAudio. It's a very informative site, with a lot of driver reviews, ideas, etc.

jmoreno150
05-24-2007, 01:11 PM
ma audio has a good one

ronvdp
09-17-2007, 02:59 AM
No, your hu has all the stuff you need built right in. Read the manual. You have to flip a switch on the side of the hu. Take it out of the dash and slide the case out of the chassis, youll see a switch called network, switch it to that and reset the unit. You will then find the tuning selection in the audio section. It takes awhile to tune the comps but in the end its worth it. Make shure the front rca go to the tweeter amp and the rear to the mid amp. If you screw that up, you risk sending the wrong signal to your tweets and can blow them.

I think the RCA recommendation is backwards, rear to tweeter, front to mids. I'm sure this is pretty late but I just did this in case anyone else tries it.

DejaWiz
09-17-2007, 09:33 AM
I think the RCA recommendation is backwards, rear to tweeter, front to mids. I'm sure this is pretty late but I just did this in case anyone else tries it.

Correct. Although the RCA's should be labeled this way on the unit itself to avoid confusion.

SQChevy
09-17-2007, 02:52 PM
If your wanting a really nice active crossover/eq then got with the Alpine PXA-H700 (or 701 with controller) I think you can get the combo around 500 on ebay, Maybe even cheaper. It has 31-band EQ and you can split it up by Front 1, Front 2, Rear, and Sub (I use Front 1-Tweets, Front 2-Midrange, Rear-Front Sub, Sub-Rear Subs). You can adjust by L/R separate or together. It also gives you full crossover ability and phase shift and time adjustments. It is one of the better ones out there, plus if you have an optical output then you keep the signal digital all the way through processing. It also gives you lots of flexibility in how you want to set it up.