4-Channel amps
- Thread starter theDRIZZLE
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K, so you like the Eclipse EA3422 without LOCs? ANd you like the Eclipse better then the Alpine 250? That would be easier to hook up for sure. So just cut the speaker wires from the HU and run then straight to the Eclipse and the other ends to the outs on the amp right? I've never installed with a factory HU lacking RCAs and want to make sure I have it right before I start cutting wires.
As for the 6" I know it wont be rattling, but I'm sure I'd hear the bass when there is none from the 6x8s wouldn't I? A sub box is out of the question, so it's this 6" or nothing really. I may just go with the Eclipse and the 4 Polk momos and see how that sounds. I know the 6" would quad, but I'm just looking for as much bass as I can get and anything that comes from it would be a real bonus. I thought about the test box for it, I just assumed being a JL, being in a hatchback/van type of vehicle that the sound would travel well and be better then nothing.
As for the 6" I know it wont be rattling, but I'm sure I'd hear the bass when there is none from the 6x8s wouldn't I? A sub box is out of the question, so it's this 6" or nothing really. I may just go with the Eclipse and the 4 Polk momos and see how that sounds. I know the 6" would quad, but I'm just looking for as much bass as I can get and anything that comes from it would be a real bonus. I thought about the test box for it, I just assumed being a JL, being in a hatchback/van type of vehicle that the sound would travel well and be better then nothing.
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1sty has some good points.
First off, you're not gonna get the cover back on. It will rattle. So if the cover must be off, you might as well utilize another 1-1.5" of your trunk space to go with the 8" subwoofer. the ID8v3 will sound good with anything from 150-300w and will help fill out the low end where your 6x8s leave off. A 6" sub is a great way to get bass up-front if installed in the doors but if you put it all the way in the rear your 6x8"s will easily over power it and make all your hard work useless.
With that said, working with fiberglass is not easy. Here is an example of the work that goes into fiberglassing a custom enclosure...
http://web.njit.edu/~cas1383/proj/Glassing3/index.htm
If done right, you could pull out the enclosure and sell it when you get rid of the car. If you're good, you will be able to fabricate a grill for the subwoofer also so your groceries and kid's toys don't damage it. You can also buy prefab grills but they don't look as nice.
The alternative is to just build a simple MDF box for a single 8" subwoofer that has quick-disconnects on the speaker wires. When you need the space, you could easily remove it and put it in the garage.
First off, you're not gonna get the cover back on. It will rattle. So if the cover must be off, you might as well utilize another 1-1.5" of your trunk space to go with the 8" subwoofer. the ID8v3 will sound good with anything from 150-300w and will help fill out the low end where your 6x8s leave off. A 6" sub is a great way to get bass up-front if installed in the doors but if you put it all the way in the rear your 6x8"s will easily over power it and make all your hard work useless.
With that said, working with fiberglass is not easy. Here is an example of the work that goes into fiberglassing a custom enclosure...
http://web.njit.edu/~cas1383/proj/Glassing3/index.htm
If done right, you could pull out the enclosure and sell it when you get rid of the car. If you're good, you will be able to fabricate a grill for the subwoofer also so your groceries and kid's toys don't damage it. You can also buy prefab grills but they don't look as nice.
The alternative is to just build a simple MDF box for a single 8" subwoofer that has quick-disconnects on the speaker wires. When you need the space, you could easily remove it and put it in the garage.
So the 6x8s would over power the sub even tho the sub would cover lower hz? I didn't think that would happen. I might just go with the amped 4 6x8s and hope they provide enough fullness as the sub box isn't an option. As for the 8", that would require it hanging out and more power which means a bigger amp that won't fit under the front seat. So, I wouldn't be able to get the 200w+ to that 8" and all my 6x8s. So power and space would be an issue. I figured I could bridge channels 3 & 4 and feed the rear 6x8s and the JL 6w0.
Damn. Well, ok, so the Eclipse EA3422 is a good choice to feed 4 6x8 Polk momos and I don't need LOCs?
Damn. Well, ok, so the Eclipse EA3422 is a good choice to feed 4 6x8 Polk momos and I don't need LOCs?
Aberration
Member
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- 2001 ES Proteg
If he's insistaent on saving room and not putting box back there... would one of the aftermarket 6.5 under seat loaded boxes work for him? Would the quality be comparable or atleast make up for not having to do all the fiberglass work in the small compartment?
Aberration- Another limitation, there is no room under the seats for a box 
There's barely enough room for an amp under the passenger seat. The seats have wires for seat belts and airbags under them along with vents aimed towards to rear for HVAC and the 2nd row has storage under them going to the ground and the 3rd row lays flat to the ground when collapsed.
So, it's the storage compartment or nothing, and possibly the lesser power hungry 6w0 or nothing. I'm just really limited unfortunately, but I wanted to hear any and all options before I commit to anything. I didn't think the 6w0 would be drained out, so I may hold off on that at first and see what happens.
There's barely enough room for an amp under the passenger seat. The seats have wires for seat belts and airbags under them along with vents aimed towards to rear for HVAC and the 2nd row has storage under them going to the ground and the 3rd row lays flat to the ground when collapsed. So, it's the storage compartment or nothing, and possibly the lesser power hungry 6w0 or nothing. I'm just really limited unfortunately, but I wanted to hear any and all options before I commit to anything. I didn't think the 6w0 would be drained out, so I may hold off on that at first and see what happens.
It all comes down to a matter of priorities and compromises. IF ther'es underseat room, a single sub would be alright if you were simply trying to add some lowend to a fectory stereo, or deck-powered speakers. but you're really going through alot of expense and effort for little gain. I messed around wiht my SSMB8's before I put them in my doors and made a small box for under the seat of my buddy's outback. It was a bit of an added kick, but nothing at all worth doing. and once we had a decent amp and a pair of 6.5" components in the doors, it became an obvious crutch and he quickly accepted a tradeoff of a bit of precious cargospace for a comp VR in a 10" truckbox. Alot of the small solutions really lack the kind of power needed to keepup with anything, essentially you're only extending frequency responce 1/3 octave or so, and eitherway this general range is in the same area as cabin gain anyways. Not ot mention the fact that it's 100% likely that proper crossovers won't be available or atleast implimented. and at that, it's again for a very narrow range. If you really want to get sneaky, move the mid/highs to the kickpanels, and put a PAIR of midbass speakers in the doors. This gives you essentially a fairly large "cabinet" Plus it keeps a pair of them for twice the surface area, not to mention retaining stereo sound (a speaker playing in this range will quite likely play into imaging)
EItherway, I think toomuch forthought is taking plae here and not enough "do it and see what it sounds like" I'd start with the 4ch and a NICE set of front speakers, see how that plays and go from there. Agian if you're really cinvinced that 6" subs are the thing to do, TRY IT FIRST. grab some perhaps cheap ones even form parts express or whatever, and pt them in a cheap and dirty box just to see if the added responce is even anything worth your while.
keep in mind that moving up to the next size sub eventhough it doesnt sound like much REALLY is. DUe to the way that areas of circles work, adding a very small amount to the diameter nets you a substancially larger gain in surface area whihc is wha tit takes to make more bass. for example a single 12 is roughly about 95% of the same area as a pair of 10's not very sure on actual cone area of smaller subs, but I'd say a single 8 is atleast twice the area of a 6.
EItherway, I think toomuch forthought is taking plae here and not enough "do it and see what it sounds like" I'd start with the 4ch and a NICE set of front speakers, see how that plays and go from there. Agian if you're really cinvinced that 6" subs are the thing to do, TRY IT FIRST. grab some perhaps cheap ones even form parts express or whatever, and pt them in a cheap and dirty box just to see if the added responce is even anything worth your while.
keep in mind that moving up to the next size sub eventhough it doesnt sound like much REALLY is. DUe to the way that areas of circles work, adding a very small amount to the diameter nets you a substancially larger gain in surface area whihc is wha tit takes to make more bass. for example a single 12 is roughly about 95% of the same area as a pair of 10's not very sure on actual cone area of smaller subs, but I'd say a single 8 is atleast twice the area of a 6.
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FWIW I grafted kicker ssmb8's into my doors. They're a very shallow mount 8" midbass speaker and I managed to make a .475" spacer ring that made installation relatively painless (aside from lining thing sup right).
When I first hooked them up I was pretty astounded especially after the disappointing performance in my buddys' car. but a pair of them with some airspace behind them is fairly impressive. IF I play them simply lowpassed as if they were subs, they'll get down there much lower than I'd assumed possible. Not quite ghetto-thug-cruiser low, but definately low enough that I didn't notice I'd forgot to put my subamp's fuse back in until I cued up some WuTang. http://www.msprotege.com/forum/showthread.php?t=122183&page=1&pp=15 Not that I've got any clue wha a 5's door is gonnalook like, but I'd say that this was 100% easier than fiberglassing a box for a 6WO would be. and likely quite a bit more effective. Of course it will also involve meaking kickpanels for the mids and highs which have now been displaced, but that's another story. and still not as involved as glassingup a subbox.
When I first hooked them up I was pretty astounded especially after the disappointing performance in my buddys' car. but a pair of them with some airspace behind them is fairly impressive. IF I play them simply lowpassed as if they were subs, they'll get down there much lower than I'd assumed possible. Not quite ghetto-thug-cruiser low, but definately low enough that I didn't notice I'd forgot to put my subamp's fuse back in until I cued up some WuTang. http://www.msprotege.com/forum/showthread.php?t=122183&page=1&pp=15 Not that I've got any clue wha a 5's door is gonnalook like, but I'd say that this was 100% easier than fiberglassing a box for a 6WO would be. and likely quite a bit more effective. Of course it will also involve meaking kickpanels for the mids and highs which have now been displaced, but that's another story. and still not as involved as glassingup a subbox.
Poseur- I have a pair of new Polk Momos so I guess I'll get a second pair for the rear and feed them an Eclipse.
Wow, 8" in your doors!?!? HAHA, good job, nice batch of pics of the install. OK, if I did go with the 8", any ideas about my power issue? I only have room for maybe 10x11x2 or so amp and most 4 channels that size max at 60w per channel. I can maybe bride channels 3 & 4 for the 8" to get 70w each channel or something.
If I were to front mount an 8", how could I cover it/portect it? I'll take some more measurements and see what I can figure out. But I still need to power it.
Oh and out of curiosity, what would I need, the dual 4, or single 2 or what (for the Image Dynamics ID8v3)
Wow, 8" in your doors!?!? HAHA, good job, nice batch of pics of the install. OK, if I did go with the 8", any ideas about my power issue? I only have room for maybe 10x11x2 or so amp and most 4 channels that size max at 60w per channel. I can maybe bride channels 3 & 4 for the 8" to get 70w each channel or something.
If I were to front mount an 8", how could I cover it/portect it? I'll take some more measurements and see what I can figure out. But I still need to power it.
Oh and out of curiosity, what would I need, the dual 4, or single 2 or what (for the Image Dynamics ID8v3)
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There are a few 5-channel amps on the market that could be used to power two sets of speakers and a subwoofer. I'm not sure whether they will fit under the front seats of a Mazda5 though.
If you power a subwoofer off a single channel you usually want the 4 ohm DVC model so you can wire it for 2 ohms. If you bridge an amplifier to power the subwoofer you usually want the 2 ohm DVC or 4 ohm SVC model so you can wire it for a 4 ohm total load. Choose the amp first, then we can can help you choose the subwoofer if this is the route you take.
There are plenty of options if you are a good fabricator, but I sense that you are just looking for stuff to install in factory locations. That being the case, I think you are on the right track with two pairs of speakers and a 4-channel amplifier.
I would recommend a set of components for the front though. You usually get better bass response and the transition between woofer and tweeter is much smoother with an external crossover filtering the signal appropriately.
If you power a subwoofer off a single channel you usually want the 4 ohm DVC model so you can wire it for 2 ohms. If you bridge an amplifier to power the subwoofer you usually want the 2 ohm DVC or 4 ohm SVC model so you can wire it for a 4 ohm total load. Choose the amp first, then we can can help you choose the subwoofer if this is the route you take.
There are plenty of options if you are a good fabricator, but I sense that you are just looking for stuff to install in factory locations. That being the case, I think you are on the right track with two pairs of speakers and a 4-channel amplifier.
I would recommend a set of components for the front though. You usually get better bass response and the transition between woofer and tweeter is much smoother with an external crossover filtering the signal appropriately.
chuyler- The fronts of the 5 is components, the tweets should be fine keeping them factory. The polk momos come with their external xover and I got bought them $200 so I can't really replace them 
As for amps, my two current options (that I've seen) are-
Alpine MRP-F250
Eclipse EA3422
Assuming the Eclipse is the better choice and I'm leaning towards it, what ID sub would I get?
Yes, my basic goal is as stock looking as possible. This is a single 'family' car and will become my wife's once we get a second car if we ever need it. We both work at home so the 1 car has done us well for quite a while. We'll be adding the roof mount DVD next for the kiddies, but I have to have better stereo sound, it's driving me crazy.
As for amps, my two current options (that I've seen) are-
Alpine MRP-F250
Eclipse EA3422
Assuming the Eclipse is the better choice and I'm leaning towards it, what ID sub would I get?
Yes, my basic goal is as stock looking as possible. This is a single 'family' car and will become my wife's once we get a second car if we ever need it. We both work at home so the 1 car has done us well for quite a while. We'll be adding the roof mount DVD next for the kiddies, but I have to have better stereo sound, it's driving me crazy.
Kid Red said:
This subject brings up the good old Fletcher-Muson Curve.
http://www.webervst.com/fm.htm
This curve shows us how the human ear does not detect all frequencies at the same sensitivity. In other words, by this graph, we see that the human ear is much more sensitive to our own vocal range and hence hear it louder then sub bass, even if the sub bass is at the same level. This can not be escaped and it is also why when a system is tuned to even through out the entire frequency range, many people will not even know a subwoofer is present.
Now keep in mind that DB-SPL or volume as most poepl will call it (how loud something is in relation to something else) is determined by:
1. Applied power
2. Effeciency
3. distance to the listener
4. area of the driver (what ever is creating the sound wave)
5. The Xmax of the driver (how far it can push out and pull in)
6. The listeners sensitivity to the sound being played
So if you have 4 6" midrange drivers each with 50 watts powering them playing a given sound and all within a few feet from your ears...how in the world is a single 6" subwoofer going to match or as it should, surpass the output level of those speakers so that your ears will hear everything evenly especialy when that single subwoofer is twice the distance from you as any of the speakers.
- Answer class? It can't.
Even if you put that subwoofer in your doors ot under your seat, you will still not hear it. Also, although advertized as a subwoofer, it is not all that great of one since it has the same limitations as any other small cone speakers so it ends up making a better midbass driver then anything else.
So if you are using 4, 6" speakers at 90 db of effeciency(polk momo's...NICE SPEAKER!!(thumb) ) then you are dedicating 50 watts to each speakers then you have 113.04 square inches playing say 1 khz at 107 db at full power. The added cone area brings us up to 113db. By the Fletcher Munson curve, we will need a subwoofer to be atleast 3db louder to hear it evenly with the mids. However the JL 6W0 is only 82 db effecient so to do this, we will need to power the 6W0 with about 2064 watts of power to get it to overcome its lower effeciency AND its lack of cone area. Of coarse the JL can not handle more then 75 watts rms so its output will be capped around 100db. to make this WORSE, the JL is twice the distance form your ears as is the other drivers so it will take an immediate 6db cut in preceived volume at the drivers seat so now its down to 94 db which is precivably 1/2 as loud as 113 db.
Now this math took ALOT of short cuts but the idea stays consistant. We miss things like cabin gain, destructive interference, loss do to vibration, and all that fun stuff. It also should be known that the effeciency rating is not accurate as the power goes up based on the box being used by a subwoofer and another host of problems.
Lets continue a bit here. So if we still need to get up to 113 db then we need a sub capable of both a large enough cone area, and a excursion distance that can properly pressurize the air. Since I am not going to dive into logarithmic math here I will again take short cuts. So if we have a 12W0 that has four times the cone area and further excursion capabilities, then at say 75 watts we can assume that it will be ~10db louder then the 6" was. So instead of being at 94 db it will be at 114, add to that it can take twice the power as the 6W0 and we now have a sub system that can produce 117 db. Which by the fletcher Munson Curve, is exactly where we want to be for the ear to precieve the bass evenly.
Again, for those of you mathmaticly knowledgable of accoustics:
I KNOW THIS IS NOT ACCURATE!! However the basic idea behind it is so the quick and dirty math is to simplify things.
By this, I would suggest getting a simple to drop in sub box that already has a subwoofer and does not require a ton of power. This would be my choice if you are running polk mono's with a 4 cahnnel amp on them:
http://mobile.jlaudio.com/products_enclosures.php?menu=9&prod_id=321
This box is TINY!
It will be barely noticable and the space it take sup will not be missed. Worst case, just remove it when you have to. It takes all of 20 seconds.
Also don't waste amplifer power on the rears. You can use either of those amps to power the front speakers and the subwoofer. Then use the deck to power the rears. Also, consider getting the less expensive polk coaxle speakers that just drop in for the rear if you must replace them at all.
The Eclipse was a great amp for us. The alpine is new so I do not know how good it is or is not yet. by simple reputation I would use the eclipse in this case.
http://mobile.jlaudio.com/products_enclosures.php?menu=9&prod_id=321
This box is TINY!
It will be barely noticable and the space it take sup will not be missed. Worst case, just remove it when you have to. It takes all of 20 seconds.
Also don't waste amplifer power on the rears. You can use either of those amps to power the front speakers and the subwoofer. Then use the deck to power the rears. Also, consider getting the less expensive polk coaxle speakers that just drop in for the rear if you must replace them at all.
The Eclipse was a great amp for us. The alpine is new so I do not know how good it is or is not yet. by simple reputation I would use the eclipse in this case.
1sty- Wow, my head is spinning from that very detailed explanation of why the 6w0 would be inadequate. Thanks for taking the time to share. I'm glad you like the Polk momos, I think they have very detailed and full sound. Also, good to know your thoughts on the Eclipse, I think I'll order that this week if possible.
As for the sub, I know that box you linked to is small, but I would rather spend an entire weekend and a little cash attempting to to make my rear compartment into a sealed enclosure to best utilize what space we have. You have to keep in mind, almost any time we use the car, the baby's stroller will be in the van, so there would be no room for the sub 75% of the time. It's hard to accurately note every exact reason why I can't have a sub from a message board writing as I type, but for various reasons I am forced to either go without the sub, or attempt to put on in that compartment.
If the ID is over kill for an 8", is there a less power hungry sub I can get?
So, if I don't amp the rears, will I even hear them? I'll need some explanations on the finer points
Other 8" sub options-
Kicker round or square 8"
Polk Momo to match Polk momo 6x8s
JL Audio 8W3
As for the sub, I know that box you linked to is small, but I would rather spend an entire weekend and a little cash attempting to to make my rear compartment into a sealed enclosure to best utilize what space we have. You have to keep in mind, almost any time we use the car, the baby's stroller will be in the van, so there would be no room for the sub 75% of the time. It's hard to accurately note every exact reason why I can't have a sub from a message board writing as I type, but for various reasons I am forced to either go without the sub, or attempt to put on in that compartment.
If the ID is over kill for an 8", is there a less power hungry sub I can get?
So, if I don't amp the rears, will I even hear them? I'll need some explanations on the finer points
Other 8" sub options-
Kicker round or square 8"
Polk Momo to match Polk momo 6x8s
JL Audio 8W3
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The ID8v3 will sound fine with the 140w from the bridged rear channels of the Eclipse amp. It's one of the best 8" subs out there whether you've got 100w or 300w. Where do you plan on ordering it from? Eclipse does not authorize online sales (except for limited items on Crutchfield) so if you buy it online you won't be getting a warranty.
There are other amps out there that can give you more power for the sub but I'm not sure what your budget is. For example, the Rockford Fosgate Punch P4004 will give you 2x50 + 1x200. The Infinity Reference 7541a is also a nice amp and will give you 2x111 + 1x278. I like Eclipse (I am running their speakers and subwoofers now) but I'm not a big fan of their amplifiers.
I am confident that you could get an 8" sub into that compartment. The air space looks about right too. However, fiberglass is a messy project and things never go smoothly the first time. Do as much research as you can on fiberglass box building, post some questions, and do a little test project before you attempt your final box.
There are other amps out there that can give you more power for the sub but I'm not sure what your budget is. For example, the Rockford Fosgate Punch P4004 will give you 2x50 + 1x200. The Infinity Reference 7541a is also a nice amp and will give you 2x111 + 1x278. I like Eclipse (I am running their speakers and subwoofers now) but I'm not a big fan of their amplifiers.
I am confident that you could get an 8" sub into that compartment. The air space looks about right too. However, fiberglass is a messy project and things never go smoothly the first time. Do as much research as you can on fiberglass box building, post some questions, and do a little test project before you attempt your final box.
See how the ID8v3 holds up to other 8" subwoofers...
http://forum.carstereos.org/showthread.php?p=468313
http://forum.carstereos.org/showthread.php?p=468313
The problem red is that playing with fiber glass for the first time is going to cost you several weekeds and likely a panel or 2 from the dealership.
Overall, that JL box I linked will likely stick out less then 3 inches from the back seat plus you can beat the hell out of it. So throw everything you have ontop of it and don't bother worring about it. Don't discount it until you atleast see it.
Doesn't the floor of the trunk have an open compartment?
Overall, that JL box I linked will likely stick out less then 3 inches from the back seat plus you can beat the hell out of it. So throw everything you have ontop of it and don't bother worring about it. Don't discount it until you atleast see it.
Doesn't the floor of the trunk have an open compartment?
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chuyler1- I just read most of the thread after searching on google I think I'm definately going with the ID8v3, just, which one, the dual 2 or the dual 4?
You don't like Eclipse? I've read good things-that they are clean and are 'highly recommended' at caraudiocentral.net. I don't really have a budget, but I don't to spend too much on the amp. I still have to get the sub, rear Polks, supplies for the enclosure, roof mounted DVD player AuxMod for my iPod....
The Fosgate and Infinity amps are 16" long, can't fit either. Any other choices? I was set on the Eclipse, so now I'm a bit flustered. What about the Alpine F250? Or the soundstream picasso PCA4.400?
I saw the Eclipse on woofersetc.com, only place I could find it. I understand the warranty issue, but what can I do?
So you think that space will house the ID8? Will it need a lot of fill? I see the ID8 can go .20 cft on the enclosure, that's the smallest I've seen for an 8". Fiberglassing may be messy, but I'm handy and determined. As long as I have the tools and decent instructions and lots of tape and tarp to protect the car
btw- thanks for all the awesome insight, I'd be quite stuck without the info I'm picking put here. I keep refreshing the page because I'm getting excited and want more input.
I think I'm definately going with the ID8v3, just, which one, the dual 2 or the dual 4?You don't like Eclipse? I've read good things-that they are clean and are 'highly recommended' at caraudiocentral.net. I don't really have a budget, but I don't to spend too much on the amp. I still have to get the sub, rear Polks, supplies for the enclosure, roof mounted DVD player AuxMod for my iPod....
The Fosgate and Infinity amps are 16" long, can't fit either. Any other choices? I was set on the Eclipse, so now I'm a bit flustered. What about the Alpine F250? Or the soundstream picasso PCA4.400?
I saw the Eclipse on woofersetc.com, only place I could find it. I understand the warranty issue, but what can I do?
So you think that space will house the ID8? Will it need a lot of fill? I see the ID8 can go .20 cft on the enclosure, that's the smallest I've seen for an 8". Fiberglassing may be messy, but I'm handy and determined. As long as I have the tools and decent instructions and lots of tape and tarp to protect the car
btw- thanks for all the awesome insight, I'd be quite stuck without the info I'm picking put here. I keep refreshing the page because I'm getting excited and want more input.
Dual 2Kid Red said:chuyler1- I just read most of the thread after searching on google
Kid Red said:
Its just not up to powering the ID sub as much as another amp would be.
Kid Red said:
Buy it or the alpine from an authorized dealer
Kid Red said:So you think that space will house the ID8? Will it need a lot of fill? I see the ID8 can go .20 cft on the enclosure, that's the smallest I've seen for an 8". Fiberglassing may be messy, but I'm handy and determined. As long as I have the tools and decent instructions and lots of tape and tarp to protect the car
Not without cutting out the back of the panel and fabricating a new cover.
1sty- I'm not too overzealous and I'm not too brave either. I've seen lots of tape and tin foil and tarps, etc being used. I will do more research first and I'd probably do a trial run to get the hang of it. I don't want to mess up the car at all, so I wouldn't or won't do it, depending on how it all goes. I'd rather have no sub then a screwed up interior or an inadequate enclosure.
I just can't go with a box.
I just can't go with a box.
