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rodneypierce
02-20-2012, 07:08 PM
Alright guys, Im pretty new to the whole active thing. OK, really new. I just put a set of Aura 5.25 comps in my 98 Grand Prix. I thought they sounded great at first (coming from blown factory speakers) but now the more and more I listen to them, the less and less I like them. They just seem to be missing something. So, I went active, and dont think I will ever go back. There is so much adjustment. BUT, no matter what I adjust (crossover and slope only, as I dont have an RTA to start messing with the PEQ) I cant get them to sound like I had hoped. They just dont seem to have a good transition if you will, and just dont sound good. So, long story short, Im looking to upgrade to 6.5" midrange/midbass driver, and a good tweeter.

Im all for the "DIY" stuff.

Below is what I have for specs:
Eclipse CD7200MKII HU
MB Quart 5 channel amp. 55x4 @ 4 ohms to power the tweeters and midrange/midbass.

Im not worried about the sub, as I have that picked out already Im thinking. (10 inch Polk MM or IDQ)

And, speakers are mounted in the factory door locations. Tweeters are on the a-pillar or can go anywhere on the dash. I dont really have room on the door panel to mount the tweeter.

Any help or suggestions would be much appreciated! Thanks guys!!

Why So Cereal?
02-20-2012, 08:50 PM
Budget?

ngsm13
02-20-2012, 09:09 PM
What are your crossover points/slopes like?

rodneypierce
02-20-2012, 09:32 PM
Tonight on the way home from work I actually hit onto something. I cant remember what i have it set to right at this moment, but give me a few minutes and I will run out and get them. Its honestly not bad where it sets right now, but Im still looking for more (arent we always in this hobby?). I know I have the tweets crossed really high in order to get them to sound decent, and not harsh.

I also thought about adding a midbass in a kick panel, and using the current component set, with the passive x-over for my "high" channel, then the midbass for my "mid" channel.

rodneypierce
02-20-2012, 10:10 PM
OK, here we go:
Sub - 80hz 12db
mid H - 125 24db
mid L - 3.15k 12db
high - 5k 24db

06goat
02-20-2012, 10:18 PM
Drop your tweeter down a bit. And drop your mid from 125 to like 80. You are basically missing the 4k range since youre tweeter is sloped so steep and that might be why youre not happy.

ngsm13
02-20-2012, 10:18 PM
Fair enough, pretty good starting point.

I'd say a speaker and/or amplifier upgrade is in order.

ngsm13
02-20-2012, 10:19 PM
Drop your tweeter down a bit. And drop your mid from 125 to like 80. You are completely missing the 4k range and that might be why youre not happy.
Not really. Also with 5.25's I would drop them too low as they tend to breakup with heavy midbass, especially IB in a door panel.

rodneypierce
02-20-2012, 10:25 PM
Drop your tweeter down a bit. And drop your mid from 125 to like 80. You are basically missing the 4k range since youre tweeter is sloped so steep and that might be why youre not happy.

They start to sound like *** any lower then what I have them. To me anyhow. This is where its crystal clear, and thats what I was looking for. Thus why I raised the midrange up a little higher to compensate. It currently sounds the best that it has yet. And the 5.25 distorts down that low. It will play that low all day at a medium volume level, and rattle the hell out of the door. But turn up the volume and it is quick to distort. Where I have it set is the cleanest yet still gives some bottom end. And that is why I used a 12db slope instead of a 24db slope on the low pass for the mid. Stretch it out abit more to hopefully pick up a little bit of that 4k range.

Fair enough, pretty good starting point.

I'd say a speaker and/or amplifier upgrade is in order.

Fair enough. What would you recommend? And what did you think about that kick panel idea with a midbass, and using the current component set for the high's. I would be using the passive x-over for them, and running them off the active "high" output.


Not really. Also with 5.25's I would drop them too low as they tend to breakup with heavy midbass, especially IB in a door panel.

^^ This pretty much sums it up!

06goat
02-20-2012, 10:26 PM
Not really. Also with 5.25's I would drop them too low as they tend to breakup with heavy midbass, especially IB in a door panel.

Didnt see the 5.25 part, my bad. But 4khz has got to be pretty **** attenuated.

thehardknoxlife
02-20-2012, 10:32 PM
Before you do anything look into deadening the door(sealing holes as well) and putting some foam behind the driver. It makes a big difference.

rodneypierce
02-20-2012, 10:35 PM
Before you do anything look into deadening the door(sealing holes as well) and putting some foam behind the driver. It makes a big difference.

I have that in the works as well. I got a quote from Don at Sounddeadenershowdown for the following:

Front Doors (each):
5 CLD Tiles, outer skin
1 CLD Tile, cut into smaller pieces, inner skin
1 CLD Tile, cut into smaller pieces, trim panel
Extruded Butyl Rope
5.3 ft² MLV
7.9 ft² 1/8" CCF
5.3 ft² 3M Thinsulate Acoustic
2.5 Velcro Strips, adhesive 2 sides

Rear Doors (each):
5 CLD Tiles, outer skin
1 CLD Tile, cut into smaller pieces, inner skin
1 CLD Tile, cut into smaller pieces, trim panel
Extruded Butyl Rope
4.5 ft² MLV
6.7 ft² 1/8" CCF
4.5 ft² 3M Thinsulate Acoustic
2.5 Velcro Strips, adhesive 2 sides

ngsm13
02-20-2012, 10:38 PM
It's not super bad, maybe adjust slopes a little more.

rodneypierce
02-20-2012, 10:40 PM
It's not super bad, maybe adjust slopes a little more.

I will work on that some tomorrow on the way to work and the way home. I just hit on this on the way home from work tonight, so didnt have much time to listen to browse tracks with any other slope settings.

ngsm13
02-20-2012, 10:40 PM
Fair enough. What would you recommend? And what did you think about that kick panel idea with a midbass, and using the current component set for the high's. I would be using the passive x-over for them, and running them off the active "high" output.

What can you fit? haha

I'd recommend some 7's if you can, and then tweeters in the a-pillars or on the dash aimed on-axis. What is your budget?

Shop around on PartsExpress and Madisound.

rodneypierce
02-20-2012, 10:46 PM
What can you fit? haha

I'd recommend some 7's if you can, and then tweeters in the a-pillars or on the dash aimed on-axis. What is your budget?

Shop around on PartsExpress and Madisound.

The max I can fit in the door buckets is 6.5 with modification. Same if I decide to go with kick panels. I would just buy the Q-Logic kick panels, which holds a max of 6.5 as well.

Obviously, the cheaper the better (I dont want to shell out 300.00 a speaker or anything like that, but dont mind paying a decent price for a solid proven speaker) And I also would like to get something to work with the current amp setup.

ngsm13
02-20-2012, 10:53 PM
Maybe some Dayton RS180's, they're a good start and fairly inexpensive. As for tweeters, look into some Vifa or Peerless in small format at Madisound. I also second the motion for deadening your doors very well, and aiming your tweeters makes a world of difference. Next step, would also be measuring speaker distances and setting up your time alignment.

rodneypierce
02-20-2012, 10:59 PM
ngsm, I actually have the TA set. But I didnt measure. I did it with pink noise and isolated each individual speaker. Its not perfect, but its not bad. I also did the phase reversing of each individual speaker, then both as a pair. Everything ended up normal except the sub is reversed, and the drivers side mid is reversed.

I couldnt understand the measurement deal. Care to explain that by chance? Something about furthest speaker, yada yada. i couldnt get the jist of it from the eclipse manual.

ngsm13
02-20-2012, 11:02 PM
ngsm, I actually have the TA set. But I didnt measure. I did it with pink noise and isolated each individual speaker. Its not perfect, but its not bad. I also did the phase reversing of each individual speaker, then both as a pair. Everything ended up normal except the sub is reversed, and the drivers side mid is reversed.

I couldnt understand the measurement deal. Care to explain that by chance? Something about furthest speaker, yada yada. i couldnt get the jist of it from the eclipse manual.
I'm not familiar with the settings on the Eclipse, do you adjust them based on distance (inches) or time (milliseconds)?

rodneypierce
02-20-2012, 11:04 PM
time. They have a calculation that converts the distance in cm to ms. so i measured the distance to each speaker center from the center of the head rest in inches, converted it to CM, but then didnt know what to do from there.

Why So Cereal?
02-20-2012, 11:09 PM
The Dayton RS 180 may not be a great choice. They would need a tweeter that plays pretty low. I'd look for a mid that can at least get u to 3khz like the silver flutes.

rodneypierce
02-20-2012, 11:20 PM
The Dayton RS 180 may not be a great choice. They would need a tweeter that plays pretty low. I'd look for a mid that can at least get u to 3khz like the silver flutes.

problem being these are **** near impossible to find. There are a few other options though.

How about some of these?

Peerless 830946 SLS 6.5" Woofer - 4 ohm: Madisound Speaker Store (http://www.madisoundspeakerstore.com/peerless-woofers-6-7/peerless-830946-sls-6.5-woofer-4-ohm/)

or these?

SB Acoustics SB17NRXC35-4, 6.5" Woofer: Madisound Speaker Store (http://www.madisoundspeakerstore.com/sb-acoustics-woofers-6-7/sb-acoustics-sb17nrxc35-4-6.5-woofer/)

or these?

Aurasound NS6-255-4A 6" Paper Cone Woofer 4 ohm: Madisound Speaker Store (http://www.madisoundspeakerstore.com/approx-6-7-woofers/aurasound-ns6-255-4a-6-paper-cone-woofer-4-ohm/)

Why So Cereal?
02-20-2012, 11:55 PM
problem being these are **** near impossible to find. There are a few other options though.

How about some of these?

Peerless 830946 SLS 6.5" Woofer - 4 ohm: Madisound Speaker Store (http://www.madisoundspeakerstore.com/peerless-woofers-6-7/peerless-830946-sls-6.5-woofer-4-ohm/)

or these?

SB Acoustics SB17NRXC35-4, 6.5" Woofer: Madisound Speaker Store (http://www.madisoundspeakerstore.com/sb-acoustics-woofers-6-7/sb-acoustics-sb17nrxc35-4-6.5-woofer/)

or these?

Aurasound NS6-255-4A 6" Paper Cone Woofer 4 ohm: Madisound Speaker Store (http://www.madisoundspeakerstore.com/approx-6-7-woofers/aurasound-ns6-255-4a-6-paper-cone-woofer-4-ohm/)

Peerless SLS is strictly midbass. no higher than 500hz, and thats pushing it. If you want Peerless go HDS I love mine and u can find them used for cheapz
Not sure on the SB's
But those Auras are great for the price.

thehardknoxlife
02-21-2012, 12:02 AM
Just throwing this out there. There is a lot more info on raw drivers at DIYMA (http://diymobileaudio.com/forum/). Pretty much everyone on that site runs an active system and use "DIY" drivers.

rodneypierce
02-21-2012, 12:04 AM
Im on there as well, but have not gotten a single response on my thread. I usually seem to get better response and answer's here.

Why So Cereal?
02-21-2012, 12:07 AM
Im on there as well, but have not gotten a single response on my thread. I usually seem to get better response and answer's here.

I post over there sometimes. Really with DIYMA its best to just find drivers you like and keep searching them on the site. Chances are they've been reviewed already. I lurk over there alot. Post rarely. My latest thread got enough attention to help me out though. Just be patient and do some searching in the mean time.

thehardknoxlife
02-21-2012, 12:31 AM
Yeah, I meant to search the site. Chances are any raw driver your looking for has been discussed thoroughly. Just type in RS180 as mentioned earlier, it's a good option and well know to perform well above it's price tag. It needs a tweeter that can cross at 1.8-2khz. There are only a few options for the tweet. I will say the best ones that can cross that low are pretty pricey.

Also, the Silver Flute 6.5 mentioned earlier is another driver that performs above it price tag, but last time I check the only place that sells them has been out of stock.

keep_hope_alive
02-21-2012, 12:43 AM
The Deadener package is fine, but sealing a door is different than deadening.

You have some gaps in your response, and that it sounds good tells me you have phase issues. Try swapping polarity on both 5.25. Reason? A 12dB/oct (and 18dB/oct) slope causes a 180deg phase shift and 24dB/oct does not.

This is the most common issue with active setups. Midbass will be uneven and muddy, highs will be harsh and unnatural. You introduced gaps to minimize the effect, Easiest is to keep all slopes at 24dB/oct. no phase shift and no issues at crossover points.

rodneypierce
02-21-2012, 08:11 AM
The Deadener package is fine, but sealing a door is different than deadening.

You have some gaps in your response, and that it sounds good tells me you have phase issues. Try swapping polarity on both 5.25. Reason? A 12dB/oct (and 18dB/oct) slope causes a 180deg phase shift and 24dB/oct does not.

This is the most common issue with active setups. Midbass will be uneven and muddy, highs will be harsh and unnatural. You introduced gaps to minimize the effect, Easiest is to keep all slopes at 24dB/oct. no phase shift and no issues at crossover points.

I actually have the drivers side 5.25's phase reversed. It brought the sound stage closer to center so I left it. When I tried to reverse both of them it scattered the stage again. I will give it another shot here though. I'll try anything.

Really appreciate the help! Im very new to this, and learning more and more every day. Thanks again guys!

keep_hope_alive
02-21-2012, 11:17 AM
then you need to verify proper polarity on every driver. having different left and right means you have polarity mixed up.

so reverse polarity on both - so you have the same focus but you blend well. right now, you dont know what actual phase is.

it is important that you use speaker wire that has identification for polarity, and that you are consistent with polarity. i use red and black heat shrink and/or electrical tape to label speaker wires for clear identification.

rodneypierce
02-21-2012, 11:22 AM
then you need to verify proper polarity on every driver. having different left and right means you have polarity mixed up.

so reverse polarity on both - so you have the same focus but you blend well. right now, you dont know what actual phase is.

it is important that you use speaker wire that has identification for polarity, and that you are consistent with polarity. i use red and black heat shrink and/or electrical tape to label speaker wires for clear identification.

No... I know the polarity of each driver. They are all regular or standard polarity EXCEPT the drivers side midrange.

I went through and isolated each speaker after I did my TA, then switched each individual speakers polarity to see if it sounded better/centered the sound better, or if it scattered it again. If it sounded better, I left it, if it scattered it, I put the polarity back to normal. Then I switched the set polarity on each PAIR of speakers to test the same, if it didnt sound better, switched the PAIR back to how it was. They are all on standard ( + to +, - to -) polarity EXCEPT for the drivers side midrange. Its reversed.

ngsm13
02-21-2012, 11:26 AM
time. They have a calculation that converts the distance in cm to ms. so i measured the distance to each speaker center from the center of the head rest in inches, converted it to CM, but then didnt know what to do from there.
Well, if your measuring tape has centimeters then just use that. Write down the distances for all four speakers.

Then use this equation:
CD5030 OWNER'S MANUAL - ECLIPSE by Fujitsu Ten (http://www.eclipse-web.com/us/download/manual/cd5030_en/audio/contents/5935.html)

To find the t/a in milliseconds of your speaker, you take the furthest speaker, subtract the chosen speakers distance, then divide by 34. Obviously given this equation, you'll see tha the speaker with the furthest distance will have zero delay. Include your subwoofer, :fyi:

The Dayton RS 180 may not be a great choice. They would need a tweeter that plays pretty low. I'd look for a mid that can at least get u to 3khz like the silver flutes.
Which is not a super big deal. It's definitely a good idea to shop around, and as mentioned DIYMA is a great source to read.

rodneypierce
02-21-2012, 11:29 AM
To find the t/a in milliseconds of your speaker, you take the furthest speaker, subtract the chosen speakers distance, then divide by 34.

OK. Thats the part I didnt understand. So its for each speaker that your doing. (distance of furthest speaker minus the speaker your doing divided by 34).

keep_hope_alive
02-21-2012, 11:36 AM
No... I know the polarity of each driver. They are all regular or standard polarity EXCEPT the drivers side midrange.

I went through and isolated each speaker after I did my TA, then switched each individual speakers polarity to see if it sounded better/centered the sound better, or if it scattered it again. If it sounded better, I left it, if it scattered it, I put the polarity back to normal. Then I switched the set polarity on each PAIR of speakers to test the same, if it didnt sound better, switched the PAIR back to how it was. They are all on standard ( + to +, - to -) polarity EXCEPT for the drivers side midrange. Its reversed.

that tells me that your wiring is mixed up for that driver. you are doing the right thing using your ears to fix your wiring issues - but good wiring methods can save that step.

it doesn't change your phase issues due to your mixing of crossover slopes. with passive crossovers - the manufacturer handles any phase adjustments and polarity changes in the terminal labeling. with active, you need to understand how each adjustment changes driver phase, and how to account for that in your wiring. sometimes you must manually reverse polarity to realign acoustic phase relative to each driver. this is why processors have a phase adjustment - to make it easy without manually changing wiring.

you won't hear the difference of relative acoustic phase between tweeter and woofer by listening for "scattered sound". for that you must focus on how the speakers blend together - which your comments above (in conjunction with your crossover settings) tell me that is where your issues are.

T/A won't fix your issues, T/A can't fix acoustic phase problems, but it can make things worse. once you have proper acoustic phase on all drivers, T/A will simply shift the center of your sound stage - left/right, up/down, close/far. you may also notice more accurate midbass as it becomes centered in the sound stage.

rodneypierce
02-21-2012, 11:40 AM
that tells me that your wiring is mixed up for that driver. you are doing the right thing using your ears to fix your wiring issues - but good wiring methods can save that step.

it doesn't change your phase issues due to your mixing of crossover slopes. with passive crossovers - the manufacturer handles any phase adjustments and polarity changes in the terminal labeling. with active, you need to understand how each adjustment changes driver phase, and how to account for that in your wiring. sometimes you must manually reverse polarity to realign acoustic phase relative to each driver. this is why processors have a phase adjustment - to make it easy without manually changing wiring.

you won't hear the difference of relative acoustic phase between tweeter and woofer by listening for "scattered sound". for that you must focus on how the speakers blend together - which your comments above (in conjunction with your crossover settings) tell me that is where your issues are.

T/A won't fix your issues, T/A can't fix acoustic phase problems, but it can make things worse. once you have proper acoustic phase on all drivers, T/A will simply shift the center of your sound stage - left/right, up/down, close/far. you may also notice more accurate midbass as it becomes centered in the sound stage.

Im sorry, but Im confused. I know for a fact the wiring on that driver was correct before i switched polarity. I used wire with a blue +++ on one lead, which went to the positive at the speaker, and the positive at the amp. All of them are marked, and Im very careful to make sure they get to the respective correct terminal.

keep_hope_alive
02-21-2012, 12:14 PM
i've felt certain before, then double checked/triple checked and realized i was wrong. it happens. i've also seen speakers with improper terminal labeling. or at the amp you make one final switch. wires with labels can be mixed up when the label is a few inches down the wire. i've even gone back and seen i put colored tape on the wrong wire.

point is, you're learning some of the quirks wth going active - things you need to think about that you haven't before.

also, it is possible you were hearing a ITD issue - depending on your source material. here are my steps

1. wire all speakers with proper polarity.
2. determine crossover slopes based on speaker parameters, response, power, and equipment capabilities.
3. change speaker polarity to account for crossover phase shift
4. T/A based on PLD to each respective ear from each voice coil center
5. listen - tweak crossovers points, tweak T/A. if i change slope, i adjust polarity accordingly.

rodneypierce
02-21-2012, 12:18 PM
10-4. Ill check it out here tonight and make certain. I will also set the TA by measuring, instead of just trying it by ear first.

And by changing slope, you change polarity, your meaning if you run a 12 or 18db slope, to switch the polarity? As earlier I believe you said that makes them 180 out.

keep_hope_alive
02-21-2012, 06:29 PM
10-4. Ill check it out here tonight and make certain. I will also set the TA by measuring, instead of just trying it by ear first.

And by changing slope, you change polarity, your meaning if you run a 12 or 18db slope, to switch the polarity? As earlier I believe you said that makes them 180 out.

correct. either increase all crossover slopes to 24dB/oct (preferred) or reverse polarity on both woofers so they are opposite of what they are now. then adjust crossover slopes to introduce some overlap.

i have spent literally dozens of hours just listening to the effects of crossover slopes and polarity. the H701 is great for doing that, great for experimentation.

ngsm13
02-21-2012, 06:54 PM
i've felt certain before, then double checked/triple checked and realized i was wrong. it happens. i've also seen speakers with improper terminal labeling. or at the amp you make one final switch. wires with labels can be mixed up when the label is a few inches down the wire. i've even gone back and seen i put colored tape on the wrong wire.

point is, you're learning some of the quirks wth going active - things you need to think about that you haven't before.

also, it is possible you were hearing a ITD issue - depending on your source material. here are my steps

1. wire all speakers with proper polarity.
2. determine crossover slopes based on speaker parameters, response, power, and equipment capabilities.
3. change speaker polarity to account for crossover phase shift
4. T/A based on PLD to each respective ear from each voice coil center
5. listen - tweak crossovers points, tweak T/A. if i change slope, i adjust polarity accordingly.
While regardless, I still agree with your process, I think that the idea of phase shift in an active setup is somewhat blown out of proportion. I think the real problem overall is the phase from an acoustic standpoint, not an electrical one. Phase problems are created by the different distances from the speakers. It’s normal for passive crossovers to be created with different slopes (and cut-off frequencies), from right to left to correct problems and staging. With active crossovers, phase shift is completely dependent on the circuit involved, whether it be IIR of FIR done onboard a DSP. It’s hard to get conclusive answers from manufacturer about the degree of phase shift which their devices incur. It’s important to note though, that the phase shift remains constand and does not change with respect to frequency, an effect of not having the impedance curve of the driver to deal with.

In the end, is it really a huge deal? I mean, acoustically the inside of a car is a nightmare. In a car we have to consider reflections, resonances, frequency, phase, responses between all of the drivers. I would say there are bigger problems for signal purity than the phase changes cause by active filters.


10-4. Ill check it out here tonight and make certain. I will also set the TA by measuring, instead of just trying it by ear first.

And by changing slope, you change polarity, your meaning if you run a 12 or 18db slope, to switch the polarity? As earlier I believe you said that makes them 180 out.
See above for a little information from my standpoint. Regardless, the process he listed is the proper order in which to address things.

keep_hope_alive
02-21-2012, 07:04 PM
In the end, is it really a huge deal? I mean, acoustically the inside of a car is a nightmare. In a car we have to consider reflections, resonances, frequency, phase, responses between all of the drivers. I would say there are bigger problems for signal purity than the phase changes cause by active filters.


See above for a little information from my standpoint. Regardless, the process he listed is the proper order in which to address things.

yes, it is very important to get acoustic phase correct at crossover points. polarity affects acoustic phase, but we know polarity is relative. phase issues at crossover points will make a good system sound like poop. is it the only challenge? certainly not. is it important? yes. normally, it is not an issue since very few systems ever run into the specific circumstances required for it to be an issue - but when it is a problem, it's noticable and important. of course, the vehicle itself plays a role - as does speaker placement.

you can test this yourself. take your front stage woofers and reverse polarity on them - leaving everything else as-is. see for yourself if you think it's a big deal to have woofers out of acoustic phase with tweeters and subs.

:)